A mission to raise the orbit of NASA’s Neil Gehrels Swift Observatory is poised for launch no earlier than Tuesday, June 30, 6:23 a.m. EDT (10:23 p.m. UTC+12), from Kwajalein Atoll, part of the Republic of the Marshall Islands in the South Pacific Ocean.

A robotic servicing satellite called LINK, built by Katalyst Space, will blast into orbit on a Northrop Grumman Pegasus XL rocket. LINK will rendezvous with, grapple, and slowly raise Swift’s altitude over several months, preventing it from re-entering Earth’s atmosphere later this year.

“Swift is NASA’s multitool when it comes to studying the cosmos,” said S. Bradley Cenko, principal investigator, Swift, NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It observes the sky using a wide range of light and rapidly points at short-lived outbursts, alerting other facilities in space and on the ground to help coordinate follow-up observations. For the last two decades, Swift has been a key player in NASA’s efforts to understand how the universe works, and we’re looking forward to getting back to that work after the boost is complete.”

Our planet’s atmosphere creates drag on all spacecraft in low Earth orbit, gradually reducing their altitudes if they don’t have propulsion systems to counteract the effect.

A recent bout of increased solar activity magnified this impact on Swift, which launched in November 2004.

Rather than allowing Swift to re-enter the atmosphere as many missions do, NASA is using the opportunity to advance the U.S. commercial satellite servicing industry.

In September, the agency contracted Katalyst to attempt to boost the observatory. The company would have less than one year to design, build, test, and launch a satellite to meet, grab, and lift Swift to nearly its original orbit.

"Swift wasn't designed to be serviced," said Ghonhee Lee, CEO of Katalyst. "By demonstrating we can quickly and cost-effectively extend its lifetime, we're creating a blueprint for servicing spacecraft that were never designed for on-orbit maintenance. If we're going to build an enduring presence beyond Earth, we need the capability to manipulate our environment in space. That means deploying robotic spacecraft that can reposition, repair, refuel, and refit satellites after launch.”

The LINK spacecraft weighs about 880 pounds and stands about 5 feet tall, about a third of Swift’s overall size. Nearly 20 feet of solar panels will power three ion thrusters and a trio of robotic arms.

LINK completed environmental testing that mimicked launch and space-like conditions at NASA Goddard this spring, as well as additional preflight assessments at Katalyst’s facility in Broomfield, Colorado.

For the boost to have its best chance of success, Swift needs to stay above an altitude of about 185 miles.

By the end of last year, however, orbital predictions generated by NASA showed the observatory reaching that threshold as early as July.

To slow Swift’s descent, the operations team at Penn State’s Eberly College of Science altered how they managed and oriented the spacecraft.

Unlike during normal operating procedures, where Swift looks at spots on the sky that are scientifically interesting, the team now selects targets that steer Swift into the most streamlined position. They also reduced power consumption as much as possible to place the satellite’s large solar panels in a more aerodynamic orientation.

Recent orbital predictions show these changes will keep Swift above critical altitude until this fall.

The satellite will launch aboard the Pegasus XL.

“We can deploy Pegasus from almost anywhere in the world using our Stargazer, a modified L-1011 aircraft,” said Wes Collier, vice president of launch systems at Northrop Grumman. “That combination of flexibility and responsive access to space will help LINK quickly reach Swift, giving the teams time to complete the boost.”

Earlier this month, engineers loaded LINK into the Pegasus XL and attached the rocket to Stargazer at NASA’s Wallops Flight Facility in Virginia. The aircraft and its payload departed for Kwajalein Atoll on Thursday, June 18, where it now awaits launch.

Once in orbit, LINK will undergo several weeks of commissioning as Katalyst evaluates the spacecraft’s propulsion, navigation, and sensor systems. It then will slowly approach and survey Swift before grabbing the observatory with its robotic arms and slowly raising the orbit to nearly 370 miles.

“This is a high-risk, high-reward mission,” said Shawn Domagal-Goldman, division director, Astrophysics, NASA Headquarters in Washington. “Swift plays a notable role in our fleet. We have much to gain by attempting this boost, which is more affordable than trying to replace Swift’s capabilities and allows NASA to advance the nation’s satellite servicing industry, for the benefit of all.”

Learn more about the Swift boost at:

https://science.nasa.gov/mission/swift/swift-boost-mission/

By Jeanette Kazmierczak
Goddard Space Flight Center, Greenbelt, Md.

Media contacts:
Alise Fisher
Headquarters, Washington
202-358-2546

Claire Andreoli
Goddard Space Flight Center, Greenbelt, Md.
301-286-1940