The space telescope NASA Neil Gehrels Swiftreleased in 2004 and dedicated to the study of gamma rays from low Earth orbit, is in trouble. Its orbit is decaying at a rate that will cause reenter the atmosphere and be destroyed at the end of next year. The space agency wants to avoid this and to do so it has selected the company Katalyst Space Technologiesbased in Arizona, for raise Swift’s orbit from its current 400 km altitude to 600 which it began orbiting two decades ago. It will be the first time a private company captures a US government satellite for repositioningand also in record time.
Other telescopes, such as Hubblethey have received maintenance missions, but it was something they were designed to do. This is not the case with the Swift, which makes the mission more complex. Now, Katalyst has announced that The ship that will be in charge of repositioning the space telescope will travel aboard Pegasusan air-launched rocket built by Northrop Grummanwhich will be launched at 12,000 meters altitude from an airplane L-1011 Stargazer from the same company.
‘It is the only launch vehicle that can meet the orbit, schedule and cost to achieve something unprecedented with an emerging technology‘, he stated in a statement Ghonhee LeeCEO of Katalyst.
Pegasus can carry almost half a ton of weight into low Earth orbit. debuted in 1990 and sum 45 missions to date, 40 of them completely successful. His most recent flight was in June 2021when it launched a ‘space domain surveillance’ satellite into orbit for the US Space Force.
According to Kurt Eberlydirector of space launches at Northrop Grumman, the company already had most of the hardware ready for this mission. ‘We have to complete the final integration and testing and develop the trajectory and guidance for the RAAN (right ascension of the ascending node) maneuver and the software, but little else‘, he pointed out.
The Katalyst mission will fly in a Pegasus XLa slightly larger and heavier version of the air-launched rocket. Terms of the deal have not been disclosed, but the total budget for Swift’s rescue amounts to 30 million dollarsincluding launch. The Swift observatory, which cost 500 million dollarswas built by Orbital Sciencesa company that in 2014 became Orbital ATK and which, in turn, was acquired by Northrop Grumman in 2018.
A rescue operation in record time
The margin to act is very small, which makes this mission play in another category compared to other assistance in low orbit that were prepared much further in advance, such as those of the Solar Maximum Mission in 1984 and the Intelsat VI (F-3/603) in 1992satellites that were captured by astronauts, repaired and repositioned into the correct orbit. Only eight months will have passed since Katalyst obtained the contract with NASA until the launch. ‘If we can do this for NASA in just eight months, I think it opens up a range of fast missions in the future.‘, he assures Kieran Wilsonvice president of technology at Katalyst.
Wilson also notes that ‘we treat that date as a firm commitment. We will continue to continually evaluate Swift’s orbital situation and determining what adaptations may be necessary,either launch at a different altitude or aim for slightly different insertions‘.
The Katalyst spacecraft will ascend to an orbit close to that of Swift and will use between two and three weeks to gradually approach. During this period you will carry out a detailed inspection from a safe distance, obtaining high resolution images to evaluate the real state of the observatory.
When you have that diagnosis, the vehicle, which measures 1.5 meters and weighs 350 kilogramswill execute the final approach and will capture Swift using its three robotic arms.
A detective work
The maneuver will not be easy. Swift was not designed to receive assistance in orbit and Their especially delicate optics cannot be oriented towards the Sun, Earth or Moon without exposing themselves to irreversible damage.. For this reason, Katalyst has been analyzing images prior to launch for months and coordinating with teams from NASA and Northrop Grumman to define the safest capture method with the least risk for the observatory.
‘There is intense detective work to find out which points of the ship we can actually grab and what their status will be.‘ says Wilson. This analysis has identified a main capture point and several promising secondary ones. After capture, the Katalyst spacecraft will lift Swift back to its initial altitude, about 600 kilometers, if all goes according to plan.
‘That altitude gave it 22 years of useful life the first time. We hope this boost will give it similar longevity in orbit‘ says Wilson.