CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In a view looking down from the top of the ML is the base of the ML and various facilities in the Launch Complex 39 area. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In view from the top of the ML is the Vehicle Assembly Building, the Launch Control Center at left and various other facilities in the Launch Complex 39 area. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In view from the top of the ML is the Vehicle Assembly Building, the Launch Control Center at left and various other facilities in the Launch Complex 39 area. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In view from the top of the ML is the crawlerway that leads to Launch Pads 39A and 39B. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A section of the metal structure is lifted away from the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is in place to lift a new steel beam for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is used to lift a section of the metal structure away from the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is in place to lift a new steel beam for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is used to lift a section of the metal structure away from the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is used to bring the final large steel beam close for installation on the base of the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A section of the metal structure is lowered by crane to the ground near the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A section of the metal structure is lowered by crane to the ground near the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is in place to lift a new steel beam for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A section of the metal structure is lowered by crane to the ground near the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is used to lift a new steel beam for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A new steel beam has arrived for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is used to lift a section of the metal structure away from the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA's Kennedy Space Center in Florida. Construction workers on lifts watch as a crane is used to bring the final large steel beam closer for installation on the base of the ML. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A new steel beam has arrived for installation on the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts are welding sections of the steel walls. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts are welding sections of the steel walls. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker trims a section of a steel beam. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – In the early morning at NASA's Kennedy Space Center in Florida, preparations are underway to lift the final large steel beam for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts cut through sections of the steel beams to prepare them for removal. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts continue to cut through a steel beam to prepare it for removal. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers have welded sections of the steel walls. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker on a lift continues to cut through a section of a steel beam to prepare it for removal. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – In the early morning at NASA's Kennedy Space Center in Florida, preparations are underway to lift the final large steel beam for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – A crane is used to lift the final large steel beam for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Dimitri Gerondidakis

CAPE CANAVERAL, Fla. – Construction workers watch as a crane is used to bring the final large steel beam closer for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Workers on lifts are monitoring the progress from above. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker trims a section of a steel wall. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Construction workers watch as a crane is used to lift the final large steel beam for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers have welded sections of the steel walls. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Construction workers on lifts continue modifications underneath the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Sections of the ML are being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker welds a section of a steel beam. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts are welding sections of the steel walls. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- A water moccasin snake travels across the gravel surface near the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Nearby, the haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In this aerial view looking down from the surface of the ML, a construction worker welds a section of metal for installation on the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – A crane is used to move the final large steel beam into position for installation on the base of the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA's Kennedy Space Center in Florida. Construction workers on lifts monitor the progress to begin attaching the final large beam to the ML structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. -- Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In this view looking up from beneath the ML, the tower and a large crane are visible. The crane is situated near the ML for lifting of heavy metal beams and other construction materials. Sections of the ML are being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker uses a measuring device on the surface of the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts perform welding work on the exterior of the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts perform welding work on the exterior of the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers perform welding on a section of metal that will be attached to the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts perform welding work on a section of metal for installation on the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers prepare a section of metal for installation on the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In this aerial view looking down from the ML, construction workers prepare sections of metal for installation. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A construction worker welds a metal beam that will be attached to the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Construction workers on lifts perform welding work on the exterior of the ML. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A large crane is situated next to the ML for lifting of heavy metal beams and other construction materials. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A large crane is situated next to the ML for lifting of heavy metal beams and other construction materials. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission-1, in 2017. Photo credit: NASA/Daniel Casper

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is being used to move scaffolding, or work platforms, around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is being used to move scaffolding, or work platforms, around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. – Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program office at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first mission, Exploration Mission 1, in 2017. Photo credit: NASA/Cory Huston

Viewed from the 274-foot level mobile launcher (ML), the Orion crew access arm (CAA) is beign installed on the tower. The CAA will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Viewed from the 274-foot level mobile launcher (ML), a technician begins installation of the Orion crew access arm (CAA) to the tower. The CAA will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Viewed from the 274-foot level mobile launcher (ML), a crane positions the Orion crew access arm (CAA) so it can be attached to the tower that will support the Space launch System (SLS) rocket at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Under the watchful eye of technicians and engineers, a crane is prepared to lift the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Seen to the right of the iconic Vehicle Assembly Building at NASA's Kennedy Space Center in Florida, a crane positions the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane is prepared to lift the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Under the watchful eye of technicians and engineers, a crane is prepared to lift the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane lifts the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane lifts the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Under the watchful eye of technicians and engineers, a crane is prepared to lift the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Under the watchful eye of technicians and engineers, a crane begins lifting the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, technicians assist as a crane lifts the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane positions the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane lifts the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

At NASA's Kennedy Space Center in Florida, a crane begins lifting the Orion crew access arm (CAA) so it can be attached to the mobile launcher (ML). The arm will be installed at about the 274-foot level on the ML tower. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Viewed from the 274-foot level mobile launcher (ML), technicians help install the Orion crew access arm (CAA) to the tower at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System (SLS), rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

With a control panel visible in the foreground, a technician begins installation of the Orion crew access arm (CAA) to the mobile launcher (ML) tower at NASA's Kennedy Space Center in Florida. NASA's Exploration Ground Systems organization has been overseeing installation of umbilicals and other launch accessories on the 380-foot-tall ML in preparation for stacking the first launch of the Space launch System, or SLS, rocket with an Orion spacecraft. The CAA is designed to rotate from its retracted position and line up with Orion's crew hatch providing entry for astronauts and technicians.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is being used to move scaffolding, or work platforms, around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. A crane is being used to move scaffolding, or work platforms, around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Scaffolding, or work platforms, have been installed around the base of the tower on the ML to continue upgrades and modifications to the structure. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. The ML is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

The engine service platform that will provide access to the core stage of the Space Launch System (SLS) rocket is moved beneath the mobile launcher (ML) in High Bay 3 of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on June 14, 2019. The large work platform is designed to provide unrestricted access to the RS-25 engines on the SLS core stage from the ML. The service platform will be used for Artemis 1 and subsequent missions. For Artemis 1, the Orion spacecraft will launch atop the SLS rocket from Launch Pad 39B and begin an approximately three-week mission that will send Orion thousands of miles beyond the Moon. Exploration Ground Systems is overseeing work on the ML.

The engine service platform that will provide access to the core stage of the Space Launch System (SLS) rocket is moved beneath the mobile launcher (ML) in High Bay 3 of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on June 14, 2019. The large work platform is designed to provide unrestricted access to the RS-25 engines on the SLS core stage from the ML. The service platform will be used for Artemis 1 and subsequent missions. For Artemis 1, the Orion spacecraft will launch atop the SLS rocket from Launch Pad 39B and begin an approximately three-week mission that will send Orion thousands of miles beyond the Moon. Exploration Ground Systems is overseeing work on the ML.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

A water moccasin snake travels across the gravel surface near the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. Nearby, the haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

Modifications continue on the Mobile Launcher, or ML, at the Mobile Launcher Park Site at NASA’s Kennedy Space Center in Florida. The haunch, a structure that will support the launch vehicle on the ML, arrives by flatbed truck at the park site. The ML is being modified and strengthened to accommodate the weight, size and thrust at launch of NASA's Space Launch System, or SLS, and Orion spacecraft. In 2013, the agency awarded a contract to J.P. Donovan Construction Inc. of Rockledge, Fla., to modify the ML, which is one of the key elements of ground support equipment that is being upgraded by the Ground Systems Development and Operations Program at Kennedy. The existing 24-foot exhaust hole is being enlarged and strengthened for the larger, heavier SLS rocket. The ML will carry the SLS rocket and Orion spacecraft to Launch Pad 39B for its first uncrewed mission, Exploration Mission-1, in 2018.

An aerial view of NASA's mobile launcher (ML) atop crawler-transporter 2 as it moves along the crawlerway to Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. In view on top of the ML is the American flag. The ML will undergo a fit check on the surface of the pad, followed by several days of systems testing. The 380-foot-tall mobile launcher is equipped with the crew access arm and several umbilicals that will provide power, environmental control, pneumatics, communication and electrical connections to NASA's Space Launch System (SLS) and Orion spacecraft. Exploration Ground Systems is preparing the ground systems necessary to launch SLS and Orion on Exploration Mission-1, missions to the Moon and on to Mars.

A view looking up at the mobile launcher (ML) in High Bay 3 of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on June 18, 2019. Work is underway to lift the engine service platform that will provide access to the core stage of the Space Launch System (SLS) rocket in the center of the ML. The large work platform is designed to provide unrestricted access to the RS-25 engines on the SLS core stage from the ML. The service platform will be used for Artemis 1 and subsequent missions. For Artemis 1, the Orion spacecraft will launch atop the SLS rocket from Launch Pad 39B and begin an approximately three-week mission that will send Orion thousands of miles beyond the Moon. Exploration Ground Systems is overseeing work on the ML.

Inside the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida, the engine service platform that will provide access to the core stage of the Space Launch System (SLS) rocket is lifted up in the center of the mobile launcher (ML) in High Bay 3 on June 18, 2019. The large work platform is designed to provide unrestricted access to the RS-25 engines on the SLS core stage from the ML. The service platform will be used for Artemis 1 and subsequent missions. For Artemis 1, the Orion spacecraft will launch atop the SLS rocket from Launch Pad 39B and begin an approximately three-week mission that will send Orion thousands of miles beyond the Moon. In view at left are the two Tail Service Mast Umbilicals. They will provide liquid oxygen and liquid hydrogen fluid lines and electrical cable connections to the SLS core stage engine section. Exploration Ground Systems is overseeing work on the ML.

The engine service platform that will provide access to the core stage of the Space Launch System (SLS) rocket arrives in High Bay 3 of the Vehicle Assembly Building at NASA’s Kennedy Space Center in Florida on June 14, 2019. The large work platform is designed to provide unrestricted access to the RS-25 engines on the SLS core stage from the ML. The service platform will be used for Artemis 1 and subsequent missions. For Artemis 1, the Orion spacecraft will launch atop the SLS rocket from Launch Pad 39B and begin an approximately three-week mission that will send Orion thousands of miles beyond the Moon. Exploration Ground Systems is overseeing work on the ML.