Technicians attach NASA's Ionospheric Connection Explorer (ICON) to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California on Sept. 10, 2019. Preparations are underway to perform a black light test on Pegasus before the port and starboard payload fairings are installed around ICON. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians perform a black light inspection of the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Sept. 10, 2019, after NASA’s Ionospheric Connection Explorer (ICON) was attached to the rocket. The Pegasus port and starboard payload fairings will be installed around ICON. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is attached to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California on Sept. 10, 2019. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, begins rollout from Building 1555 at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS. Launch is scheduled for Oct. 10, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

A stereographic view of NASA's Ionospheric Connection Explorer (ICON) in a clean room at Vandenberg Air Force Base in California, on Aug. 16, 2018. ICON will launch on a Northrop Grumman Pegasus XL vehicle, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, rolls out to the runway at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS. Launch is scheduled for Oct. 10, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, rolls out to the runway at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS. Launch is scheduled for Oct. 10, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, rolls out from Building 1555 to the runway at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS in Florida. Launch is scheduled for Oct. 10, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is attached to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California on Sept. 10, 2019. Preparations are underway to perform a black light test on Pegasus before the port and starboard payload fairings are installed around ICON. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians perform a black light inspection of the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Sept. 10, 2019, after NASA’s Ionospheric Connection Explorer (ICON) was attached to the rocket. The Pegasus port and starboard payload fairings will be installed around ICON. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians attach NASA’s Ionospheric Connection Explorer (ICON) to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Sept. 10, 2019. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, begins rollout from Building 1555 at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS. Launch is scheduled for Oct. 10, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians attach NASA’s Ionospheric Connection Explorer (ICON) to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Sept. 10, 2019. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 9, 2019. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Northrop Grumman's L-1011 Stargazer takes off from the hot pad at Vandenberg Air Force Base in California on June 6, 2018. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician performs a ultraviolet light inspection of the Orbital ATK Pegasus starboard on May 22, 2018, prior to fully mating NASA's Ionospheric Connection Explorer (ICON) to Pegasus inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians secure NASA's Ionospheric Connection Explorer (ICON) on the spacecraft separation system May 9, 2018, in a clean room inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The solar panels on NASA's Ionospheric Connection Explorer (ICON) are being deployed to test them inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Northrop Grumman's L-1011 Stargazer aircraft is at the hot pad at Vandenberg Air Force Base in California on May 26, 2018. Preparations are underway to attach the company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians complete installation of the second half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians extend the solar array on NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is in the horizontal position May 11, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. ICON is being prepared to be attached to the Orbital ATK Pegasus XL rocket. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

NASA's Ionospheric Connection Explorer (ICON) is being attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Northrop Grumman Pegasus XL vehicle is transported from Building 1555 to the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. NASA's Ionospheric Connection Explorer (ICON) is secured inside the rocket's payload fairing. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft, and travel to the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will launch aboard the Pegasus XL rocket on Oct. 26, 2018, from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside Building 1555 at Vandenberg Air Force Base in California, technicians prepare to install the first of two fins on Northrop Grumman's Pegasus XL rocket on July 30, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch NASA's Ionospheric Connection Explorer (ICON) from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians extend the solar array on NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician monitors the progress as NASA's Ionospheric Connection Explorer (ICON) is attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer soars upward after takeoff from the hot pad at Vandenberg Air Force Base in California on Oct. 19, 2018. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The Pegasus XL rocket will launch from the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

A technician operates a crane that lifts the shipping container up from NASA's Ionospheric Connection Explorer (ICON) on May 1, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician assists as NASA's Ionospheric Connection Explorer (ICON) is being attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Orbital ATK Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) spacecraft attached, is being moved on an assembly integration trailer from one high bay to another Aug. 23, 2017, at Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for the ICON mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The first half of the payload fairing for the Orbital ATK Pegasus XL rocket is inside Building 1555 at Vandenberg Air Force Base in California on Aug. 4, 2018. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the company's L-1011 Stargazer aircraft at the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. The Stargazer will take off from the hot pad and travel to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Inside Building 1555 at Vandenberg Air Force Base in California, technicians install the first of two fins on Northrop Grumman's Pegasus XL rocket on July 30, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch NASA's Ionospheric Connection Explorer (ICON) from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside Building 1555 at Vandenberg Air Force Base in California, technicians prepare to install the second of two fins on Northrop Grumman's Pegasus XL rocket on July 30, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch NASA's Ionospheric Connection Explorer (ICON) from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

NASA's Ionospheric Connection Explorer (ICON) is moved to a clean room on May 4, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Northrop Grumman L-1011 Stargazer aircraft, with the Pegasus XL rocket attached beneath, starts down the runway at the Skid Strip at Cape Canaveral Air Force Station in Florida on Nov. 7, 2018. NASA's Ionospheric Connection Explorer (ICON) is secured inside the rocket's payload fairing. The Pegasus XL rocket will be carried aloft by the Stargazer. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Northrop Grumman L-1011 Stargazer aircraft, with the Pegasus XL rocket attached beneath, starts down the runway at the Skid Strip at Cape Canaveral Air Force Station in Florida on Nov. 7, 2018. NASA's Ionospheric Connection Explorer (ICON) is secured inside the rocket's payload fairing. The Pegasus XL rocket will be carried aloft by the Stargazer. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Orbital ATK technicians remove the second half of the payload fairing for the Orbital ATK Pegasus XL rocket from its shipping container Aug. 4, 2017, at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A crane lifts and moves NASA's Ionospheric Connection Explorer (ICON) to a work stand on May 1, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the second half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A solar array illumination test is performed on NASA's Ionospheric Connection Explorer (ICON) in a clean room on May 4, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians extend the solar array on NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician assists with connections as NASA's Ionospheric Connection Explorer (ICON) is attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer is being readied for takeoff Oct. 19, 2018, from the hot pad at Vandenberg Air Force Base in California. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The Pegasus XL rocket will launch from the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians begin to install the second half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer is being readied for takeoff June 6, 2018, from the hot pad at Vandenberg Air Force Base in California. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is transported to the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. Pegasus will be attached beneath the company's L-1011 Stargazer aircraft for the trip to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians perform a black light inspection of the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Aug. 22, 2018. The Pegasus port and starboard payload fairings will be installed around NASA's Ionospheric Connection Explorer (ICON). The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL vehicle is inside Building 1555 at Vandenberg Air Force Base in California, on Oct. 8, 2018. The payload fairing is installed around NASA's Ionospheric Connection Explorer (ICON). The Pegasus XL, attached to the company's L-1011 Stargazer aircraft, will launch from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) for its move to a clean room on May 4, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The fins for Northrop Grumman's Pegasus XL rocket arrive at Building 1555 at Vandenberg Air Force Base in California, on July 30, 2018. Technicians will prepare the fins for installation on the Pegasus XL rocket, which will be attached beneath the company's L-1011 Stargazer aircraft, to launch NASA's Ionospheric Connection Explorer (ICON) from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) to be attached to the spacecraft separation system May 9, 2018, in a clean room inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Orbital ATK Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) spacecraft attached, is moved on an assembly integration trailer into another high bay Aug. 23, 2017, at Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for the ICON mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is uncrated from its shipping container on May 1, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician performs a ultraviolet light inspection of the Orbital ATK Pegasus starboard on May 22, 2018, prior to fully mating NASA's Ionospheric Connection Explorer (ICON) to Pegasus inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians secure Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), beneath the company's L-1011 Stargazer aircraft at the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. The Stargazer will take off from the hot pad and travel to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Northrop Grumman's L-1011 Stargazer prepares for takeoff June 6, 2018, from the hot pad at Vandenberg Air Force Base in California. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

NASA's Ionospheric Connection Explorer (ICON) is attached to the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California. Preparations are underway to perform a black light test on Pegasus before the port and starboard payload fairings are installed around ICON on Aug. 22, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The payload fairing for Orbital ATK's Pegasus XL rocket arrives by flatbed truck Aug. 4, 2017, at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

NASA's Ionospheric Connection Explorer (ICON) spacecraft is partially mated to the starboard faring of Orbital ATK's Pegasus XL rocket on May 21, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians install the starboard fin on the Orbital ATK Pegasus XL rocket July 8, 2017, inside Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. ICON will launch on June 15 from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians begin a black light inspection of the Northrop Grumman Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California, on Aug. 22, 2018. The Pegasus port and starboard payload fairings will be installed around NASA's Ionospheric Connection Explorer (ICON). The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) for lift and transfer to a work stand on May 1, 2018, inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician begins a ultraviolet light inspection of the Orbital ATK Pegasus starboard on May 22, 2018, prior to mating NASA's Ionospheric Connection Explorer (ICON) to Pegasus inside Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians install the aft skirt on the Orbital ATK Pegasus XL rocket July 8, 2017, inside Building 1555 at Vandenberg Air Force Base in California. When the aft skirt is installed, the rudder and fins can be installed. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATKS's Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer prepares for takeoff June 6, 2018, from the hot pad at Vandenberg Air Force Base in California. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is transported to the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. Pegasus will be attached beneath the company's L-1011 Stargazer aircraft for the trip to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians complete installation of the Northrop Grumman Pegasus XL port and starboard payload fairings around NASA's Ionospheric Connection Explorer (ICON) on Aug. 22, 2018. ICON is being prepared for its launch on the Pegasus XL rocket, which is attached beneath the company's L-1011 Stargazer aircraft. Launch is scheduled for Oct. 26, from the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians extend the solar array on NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians install the rudder on the Orbital ATK Pegasus XL rocket July 8, 2017, inside Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. ICON will launch on June 15 from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians move the first half of the payload fairing for the Orbital ATK Pegasus XL rocket inside Building 1555 at Vandenberg Air Force Base in California on Aug. 4, 2018. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer soars upward after takeoff from the hot pad at Vandenberg Air Force Base in California on June 6, 2018. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians secure Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), beneath the company's L-1011 Stargazer aircraft at the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. The Stargazer will take off from the hot pad and travel to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is prepared for a solar array illumination test in a clean room inside Building 1555 at Vandenberg Air Force Base in California on May 4, 2018. The test checks for any imperfections and confirms that the solar arrays are functioning properly. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) for a solar array deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Orbital ATK Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) spacecraft attached, is secured on an assembly integration trailer Aug. 23, 2017, inside Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for the ICON mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians removed the solar array from NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON is being prepared for its launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft. Launch is scheduled for Oct. 10, 2019, from the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

The Northrop Grumman Pegasus XL vehicle is inside Building 1555 at Vandenberg Air Force Base in California, on Oct. 8, 2018. The payload fairing is installed around NASA's Ionospheric Connection Explorer (ICON). The Pegasus XL, attached to the company's L-1011 Stargazer aircraft, will launch from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians secure Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), beneath the company's L-1011 Stargazer aircraft at the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. The Stargazer will take off from the hot pad and travel to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Inside Building 1555 at Vandenberg Air Force Base in California, technicians prepare the fins for installation on Northrop Grumman's Pegasus XL rocket on July 30, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch NASA's Ionospheric Connection Explorer (ICON) from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer is being readied for takeoff June 6, 2018, from the hot pad at Vandenberg Air Force Base in California. The company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's L-1011 Stargazer aircraft is at the hot pad at Vandenberg Air Force Base in California on May 26, 2018. Preparations are underway to attach the company's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), beneath the aircraft. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States). ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the second half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

The Northrop Grumman L-1011 Stargazer aircraft, with the Pegasus XL rocket attached beneath, is being prepared for takeoff from the runway at the Skid Strip at Cape Canaveral Air Force Station in Florida on Nov. 7, 2018. NASA's Ionospheric Connection Explorer (ICON) satellite is secured inside the rocket's payload fairing. The Pegasus XL rocket will be carried aloft by the Stargazer. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

NASA's Ionospheric Connection Explorer (ICON) arrives by truck on May 1, 2018, at Vandenberg Air Force Base in California. ICON will be offloaded and transported to Building 1555. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Orbital ATK technicians remove the first half of the payload fairing for the Orbital ATK Pegasus XL rocket from its shipping container Aug. 4, 2017, at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians begin to install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Aug. 22, 2018. ICON is being prepared for its launch on the Pegasus XL rocket, which is attached beneath the company's L-1011 Stargazer aircraft. Launch is scheduled for Oct. 26, from the Skid Strip at Cape Canaveral Air Force Station in Florida. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians install the first of two Northrop Grumman Pegasus XL payload fairings around NASA's Ionospheric Connection Explorer (ICON) inside Building 1555 at Vandenberg Air Force Base in California, on Aug. 22, 2018. The Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, will launch ICON from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

NASA's Ionospheric Connection Explorer (ICON) is in the horizontal position May 11, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. ICON is being prepared to be attached to the Orbital ATK Pegasus XL rocket. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Northrop Grumman's Pegasus XL rocket, containing NASA's Ionospheric Connection Explorer (ICON), is attached beneath the company's L-1011 Stargazer aircraft at the hot pad at Vandenberg Air Force Base in California, on Oct. 14, 2018. The Stargazer will take off from the hot pad and travel to Cape Canaveral Air Force Station in Florida. The Pegasus XL rocket will launch ICON from the Skid Strip at the Cape. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

Technicians extend the solar array on NASA's Ionospheric Connection Explorer (ICON) during a deployment test inside Building 1555 at Vandenberg Air Force Base in California on Aug. 10, 2019. ICON will launch on a Pegasus XL rocket, attached beneath the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 10. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology and communications systems.

A technician assists with connections as NASA's Ionospheric Connection Explorer (ICON) is attached to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians prepare the rudder for installation on the Orbital ATK Pegasus XL rocket July 8, 2017, inside Building 1555 at Vandenberg Air Force Base in California. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. ICON will launch on June 15 from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATK's Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

A technician installs the aft skirt on the Orbital ATK Pegasus XL rocket July 8, 2017, inside Building 1555 at Vandenberg Air Force Base in California. When the aft skirt is installed, the rudder and fins can be installed. The Pegasus rocket is being prepared for NASA's Ionospheric Connection Explorer, or ICON, mission. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on Orbital ATKS's Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.

Technicians prepare NASA's Ionospheric Connection Explorer (ICON) for mating to the Orbital ATK Pegasus XL rocket May 14, 2018, inside a clean room in Building 1555 at Vandenberg Air Force Base in California. The explorer will launch on June 15, 2018, from Kwajalein Atoll in the Marshall Islands (June 14 in the continental United States) on the Pegasus XL rocket, which is attached to the company's L-1011 Stargazer aircraft. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.