LAUNCH OF PEGASUS-XL TO REBOOST SWIFT OBSERVATORY, June 27, 2026 EDT, Kwajalein Atoll, Marshall Islands, 5:00 am EDT (9:00 pm June 26 local time)

NASA will launch a mission to try and reboost the Neil Gehrels Swift Observatory using Northrop Grumman’s Pegasus XL air-launched rocket and Katalyst Space’s LINK spacecraft. Launched in 2004, Swift’s orbit is decaying. Scientists would like to continue using it to study gamma ray bursts if LINK can boost it back into a stable orbit.

Pegasus XL will take off aboard a specially-designed Northrop Grumman L-1011 aircraft named Stargazer from Kwajalein Atoll in the Pacific Ocean in the Republic of the Marshall Islands.

At a June 17 NASA press conference, Katalyst’s Kieran Wilson said the target launch date is June 27, 2026.

Sources on the web say that that launch date is in Pacific Time, and the launch window is open 2:00 am-7:28 am Pacific Daylight Time. That’s June 27, 5:00-10:28 am Eastern Daylight Time.  At Kwajalein, it is 9:00 pm June 26-2:28 am June 27 local time.

More information is on NASA’s website, as well as on Katalyst’s, and Northrop Grumman’s.