NASA is seeking proposals from industry for raising the orbit of the Neil Gehrels Swift Observatory, a workhorse mission that has provided insights into cosmic environments and the explosion of massive stars since its launch is 2004.
)paren With atmospheric drag increasing in low Earth orbit over the lifecycle of the current solar cycle, Swift’s approximately 370 kilometers altitude is proving to be a liability. A targeted reboost could purchase years of extra observing time for its three-instrument suite, and NASA is hoping that commercial partners can demonstrate how to do it safely and affordably.
Why Swift Needs a Reboost
Swift’s harness was designed to detect the cataclysmic outbursts as they flare and then pivot within minutes to search for fading, lingering, or repeat emissions across X-ray, ultraviolet and visible light. Its Burst Alert Telescope, X-Ray Telescope, and UV/Optical Telescope have helped perform thousands of peer-reviewed studies in addition to identifying over 1,700 gamma-ray bursts. The science remains top-notch — but the weather is not playing ball.
When the sun is more active, the upper atmosphere puffs up, providing more drag on satellites that reside in low Earth orbit. Formal models, such as NRLMSISE-00, suggest that density at 350-400 km can rise by factors of 2 to 5 during solar maxima, leading to huge degradation of the orbital lifetime. A craft the size of Swift, which is about 1.5 metric tons, can quickly lose altitude without a little help, which would nudge it prematurely back into the atmosphere.
A Look Inside NASA’s Call to Industry
Swift serves as a test site in orbit of previous on-orbit servicing technology on a real-world mission by NASA at low altitude. Instead of developing a one-size-fits-all solution, the agency is asking for ideas from companies that can meet up with, inspect, and give a gentle nudge to an existing spacecraft. This would include probing whether existing commercial demonstration missions could be modified to provide some gentle pushing to a higher, more stable orbit.
Among the companies in the discussion are firms that are developing autonomous rendezvous and docking capabilities. For instance, Starfish Space has been aging inspection and proximity-operations technology for future servicing vehicles. NASA’s interest aligns with other work underway throughout its Space Technology Mission Directorate and the broader Satellite Servicing Projects Division to plant the seeds of a market for routine life extension and in-space reconfiguration services.
The agency is not exactly crowdsourcing rocket science. “It’s an end-to-end service we’re requesting, from the delivery of flight-proven hardware to the conducting of a robust safety analysis to a believable operations plan of a sensitive observatory.”
What Would an Orbit-Raise Entail?
Where Swift operates, even a 50 to 150 kilometers of upward climb can have a profound effect, reducing drag and extending lifetime by years. The needed change in velocity is generally in the tens of meters per second range — well within the capabilities of a small tug or compact propulsion add-on — the trick is doing it without putting the spacecraft at risk.
Precise rendezvous and hold points, safe corridors of approach, and avoidance of thruster plume impingement on the Swift optics and star trackers must be addressed for any visiting vehicle.
Candidates that don’t pose a toxicity or contamination risk and competition, such as the AF‑M315E “green” monopropellant (demonstrated by NASA’s Green Propellant Infusion Mission), are likely to be preferred. Teams will also have to demonstrate how they can uphold Swift’s attitude constraints while in contact, protect its thermal environment and coordinate collision avoidance efforts with U.S. Space Force’s space traffic management.
Several architectures are on the table: a free-flying tug that docks and completes a series of burns; a detachable “kick module” that bolts to a standardized interface and stays with the spacecraft; or a inspection-first approach that verifies relative navigation and proximity before committing to a gentle push. And what will count to NASA reviewers is reliability and a clear path to flight readiness on Swift’s needed timeline.
A Test Case for On-Orbit Servicing
If successful, Swift’s reboost could serve as a model mission for the future life extension of spacecraft in low Earth orbit. Most of the commercial servicing to date — like Northrop Grumman’s Mission Extension Vehicle — has been targeted at satellites in geostationary orbit. But LEO is a different animal: shorter orbital periods, denser traffic, more drag, and stringent contamination requirements for science payloads.
The timing is notable. Agencies around the world are supporting inspection and debris-removal demos — including JAXA’s ADRAS‑J and ESA’s ClearSpace-1 — and NASA has looked at commercial concepts to reboost other flagship assets, such as the Hubble Space Telescope. A successful, safe reboost of Swift would make the argument for using commercial providers to keep high-value government satellites operational rather than simply abandoning perfectly health instruments when their propellant runs low or drag builds up.
What Science Has at Stake
Swift continues to serve as the only space telescope capable of localizing cosmic explosions, and doing so quickly, then rapidly re-pointing to share them with a global network of observers on the ground and in space. A superpower in agility that has made discoveries from the most distant known gamma ray bursts to counterparts of gravitational-wave events, tying the multi-messenger sky together in near real-time.
The telescope has not run out of ideas — just altitude. A precision orbit raise would maintain a valuable science return, demonstrate critical in-space servicing capability in low Earth orbit and write the playbook for how to keep other aging but powerful spacecraft above the drag. For NASA and its industry partners, it’s an opportunity to make a potential liability into a financial boon.
