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

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.

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.

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

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.

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

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.

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

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.

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

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at the top of Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 approaches Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 begins its trek to Launch Pad 39B on Aug. 30, 2018, at the agency's Kennedy Space Center in Florida. 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.

An aerial view of NASA's mobile launcher (ML) atop crawler-transporter 2 as it begins its trek to Launch Pad 39B on Aug. 30, 2018, at the agency's Kennedy Space Center in Florida. 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

With a view of the flame trench and flame deflector below, NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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 liquid hydrogen storage tank is in view as NASA's mobile launcher (ML) atop crawler-transporter 2 makes its way up the ramp at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at the top of Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

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. 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at the top of Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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 bright blue sky serves as a backdrop as NASA's mobile launcher (ML) atop crawler-transporter 2 arrives at Launch Pad 39B on Aug. 31, 2018, at the agency's Kennedy Space Center in Florida. The ML will undergo a fit check, 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.

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. 30, 2018, at the agency's Kennedy Space Center in Florida. 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.

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

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

A crane and rigging lines are used to install the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) high up on the mobile launcher (ML) at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical is located at about the 240-foot-level of the mobile launcher and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.

A view of the Artemis I Space Launch System (SLS) and Orion spacecraft atop the mobile launcher (ML) on Launch Pad 39B at NASA’s Kennedy Space Center in Florida on April 21, 2022. Also in view are several of the umbilical connections from the ML to the rocket. The SLS and Orion atop the mobile launcher were transported to the pad on crawler-transporter 2 for a prelaunch test called a wet dress rehearsal. Artemis I will be the first integrated test of the SLS and Orion spacecraft. In future Artemis missions, NASA will land the first woman and the first person of color on the surface of the Moon, paving the way for a long-term lunar presence and serving as a steppingstone on the way to Mars.

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. -- 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