The Stargazer L-1011 carrier plane carrying NASA's Ionospheric Connection Explorer satellite, or ICON, had already taken off from its staging ground at Florida's Cape Canaveral Air Force Station when an issue was detected on the Northrop Grumman Pegasus XL rocket that was to have launched the satellite from the air at 3:05 a.m. EST (0705 GMT). The next launch opportunity for ICON is on Thursday (Nov. 8), NASA officials said.
"NASA and Northrop Grumman scrubbed today's launch of #PegasusXL due to off-nominal data received during the captive carry flight," representatives with Northrop Grumman, which built the rocket, said in a Twitter update after the launch scrub. The L-1011 Stargazer carrier aircraft has returned to Cape Canaveral Air Force Station and an investigation into the anomaly will begin soon, they added.
The launch scrub is the latest in a string of delays for the ICON mission over the last year. The satellite was originally scheduled for a launch on Dec. 8, 2017, before rocket issues forced NASA to postpone it deep into 2018. The initial launch plan for ICON called for its Stargazer L-1011 to take off from a U.S. Army base on the Kwajalein Atoll in the Marshall Islands of the Pacific Ocean. After the initial delays last year, NASA moved the staging ground for the launch to Florida's Cape Canaveral Air Force Station.
NASA's ICON satellite is in good health as engineers assess the issue with its Pegasus XL booster, Northrop Grumman representatives said.
ICON is a $252 million mission to study Earth's ionosphere, a level of Earth's uppermost atmosphere ionized by the sun's radiation, like never before. The satellite will orbit about 360 miles (575 km) above Earth and use four different instruments to track how terrestrial winds and the sun's own solar wind shape the ionosphere, which covers a region roughly 50 to 400 miles (80 to 645 km) above the planet. Scientists hope the spacecraft will help understand how those winds impact the communications and GPS signals we send through the ionosphere, as well as the satellites and spacecraft in low-Earth orbit (like the International Space Station) that fly through parts of the atmospheric layer, NASA officials said.