Hubble in a death spiral that could end as early as 2028 without a reboost
- Reference: 1772025767
- News link: https://www.theregister.co.uk/2026/02/25/hubble_orbit_decay/
- Source link:
The [1]post on Bluesky by astronomer Jonathan McDowell is a stark reminder that Hubble is heading back to Earth, possibly sooner than previously thought, as its orbit decays.
Hubble was launched into low Earth orbit in 1990, carried in the payload bay of Space Shuttle Discovery. While it remains capable of pointing its instruments and has returned breathtaking imagery over more than three decades in orbit, it cannot raise its altitude.
[2]
The observatory was serviced by a succession of Space Shuttle crews over the years, and engineers worked around hardware failures as the observatory aged. However, no amount of ground-based cleverness will stop the spacecraft from eventually re-entering the atmosphere.
[3]
[4]
The plot from McDowell makes the orbital decay clear. From an initial altitude of more than 600 km, Hubble is now well below 500 km. The more rapid descent in recent years is at least partly due to increased solar activity, which has caused Earth's atmosphere to expand, but it also highlights the need for a reboost in the next few years before the telescope becomes unrecoverable.
NASA is attempting to [5]rescue the Swift observatory and has paused most science operations after the 21-year-old spacecraft's altitude dropped below 400 km, in order to buy extra time for a reboost mission later this year.
[6]Historic NASA test towers face their final countdown
[7]NASA mulls sending a rescue rocket to boost Swift observatory's orbit
[8]NASA faces brain drain as thousands exit under voluntary resignation scheme
[9]NASA veteran warns Hubble faces death by a hundred cuts
Jared Isaacman, now NASA Administrator, mooted boosting Hubble in [10]2022 , but was ultimately rejected. Unlike Swift, Hubble was designed to be captured and serviced in space, and the last Space Shuttle servicing mission left an adapter attached to the vehicle for a future visiting spacecraft.
In 2025, Dr John Grunsfeld, former astronaut and retired associate administrator of NASA's Science Mission Directorate, [11]told The Register that Hubble faced death by a thousand cuts, decaying orbit notwithstanding. Its budget has been relatively flat for years, which means, accounting for inflation, "we're already down about 30 percent in funding for Hubble."
[12]
"They're just trying to whittle away at it," he said.
Hubble transitioned to a single-gyro mode in 2024. It has six of the devices, which are used to point the telescope, but three have failed, and a fourth is showing signs of degradation. The plan was to eke out a few more years of operational life from a spacecraft that had outlived all initial expectations.
However, without a reboost, the telescope could re-enter the atmosphere as early as 2028, according to McDowell's analysis. His plot suggests it is already on that trajectory. ®
Get our [13]Tech Resources
[1] https://bsky.app/profile/planet4589.bsky.social/post/3mfnzjhkvhc27
[2] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2aZ8qtTTVGpasd3I8RgiInwAAAsc&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[3] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44aZ8qtTTVGpasd3I8RgiInwAAAsc&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[4] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=3&c=33aZ8qtTTVGpasd3I8RgiInwAAAsc&t=ct%3Dns%26unitnum%3D3%26raptor%3Deagle%26pos%3Dmid%26test%3D0
[5] https://www.theregister.com/2026/02/12/nasa_swift_reboost/
[6] https://www.theregister.com/2026/01/07/nasa_test_stand_demolition/
[7] https://www.theregister.com/2025/08/13/nasa_mulls_sending_a_rescue/
[8] https://www.theregister.com/2025/07/28/nasa_voluntary_exits/
[9] https://www.theregister.com/2025/07/21/hubble_astronaut_budget_fears/
[10] https://www.theregister.com/2022/09/30/nasa_spacex_hubble_dragon/
[11] https://www.theregister.com/2025/07/21/hubble_astronaut_budget_fears/
[12] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44aZ8qtTTVGpasd3I8RgiInwAAAsc&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[13] https://whitepapers.theregister.com/
Re: 2028 sounds like a death sentence for Hubble
Could both be a reboost and money spent with SpaceX.
A Crew Dragon (or possibly even a Cargo Dragon, although a manned mission may be preferable) should be able to boost Hubble, and can work at that altitude. After all, they boost the ISS, and Hubble is so much lighter.
But at some point, it just isnt worth it. Hubble has been amazing , but all things must pass. Without some actual maintenance Hubble will suffer an unrecoverable failure at some point in the not to distant future.
Re: 2028 sounds like a death sentence for Hubble
Like Voyager 1 & 2?
Its working and in orbit. The cost to boost it is trivial to the cost of replacing it.
Whether the Great Pumpkin will see that or not is debatable unless NASA creates a Peace Prize to give him.
Re: 2028 sounds like a death sentence for Hubble
> Could both be a reboost and money spent with SpaceX.
> A Crew Dragon (or possibly even a Cargo Dragon, although a manned mission may be preferable) should be able to boost Hubble, and can work at that altitude. After all, they boost the ISS, and Hubble is so much lighter.
Skeptical of Trump's NASA, but perhaps Musk might do it for the PR? He could certainly use a boost of his own after everything he's done to damage his brand with science-minded types. Just read that a judge overseeing a trial against him had difficulty seating a jury, because so many potential jurors expressed hatred of him.
> But at some point, it just isnt worth it. Hubble has been amazing, but all things must pass. Without some actual maintenance Hubble will suffer an unrecoverable failure at some point in the not to distant future.
We basically don't have another option until there is a replacement on deck. The will just doesn't exist to build one right now. Awareness is coming up short, too.
Even many science-minded people think JWST is a Hubble replacement, and it's not. JWST operates in completely different wavelengths.
Re: 2028 sounds like a death sentence for Hubble
Given how SpaceX haven't managed to demonstrate getting 19 Starship tankers into orbit, and decided not to go to Mars despire their dear leader saying he would like to die there and promising a landing years ago, I'm not sure SpaceX could get its act together in time.
Re: 2028 sounds like a death sentence for Hubble
Hubble wasn't designed for in-space maintenance. Yes I know a shuttle managed it, but there isn't a docking port to attach a Dragon to, so it would need a special attachment.
There's also the risk that you boost it and the remaining gyro(s) immediately fail and you've now pushed junk into a slower-decaying orbit.
The prospect of building a capsule which could attach to hubble and provide additional attitude control (ie its own gyros) has been mooted but deemed infeasible. Cheaper/more effective to build a new telescope to stick on the front of such a vehicle.
Re: 2028 sounds like a death sentence for Hubble
Hubble doesn't meet those criteria.
With a bit of luck it will fall onto the orange one's head in the White House.
Having said that I would prefer to have a functioning Hubble telescope.
Re: 2028 sounds like a death sentence for Hubble
Oooh, given the chance I’m not sure… that’s a real difficult choice
Re: 2028 sounds like a death sentence for Hubble
>With a bit of luck it will fall onto the orange one's head in the White House.
Sadly Hubble's orbit inclination is about 28.5deg so it can't even hit Houston
Mar-a-lago on the other hand.....
as it descends
It becomes more reachable.
And as time goes on robot/telefactors get more able.
At what point do salvage rules apply?
Re: as it descends
Soon you can reach it with a ladder and a gentle push is all that is required. You just have to wear heat resistant gloves. These devices are usually a bit hot when they reach ladder altitudes.
OTOH, you can claim the device as a legitimate salvage when you can reach it from your home's roof with a ladder. Might be worth something on ebay, I guess?
Is it small enough to burn up on the way down, or are we looking at a hazard here?
It fit inside the shuttle's cargo bay. It is not that big.
From Wikipedia...
Dimensions 13.2 m × 4.2 m
Or 1x London bus. (surprisingly similar at 12 - 13.75m long)
As far as I know, no London buses have been dropped back into the atmosphere, so I'm not sure that helps the OP?
I think that was going to be a part of an upcoming episode of Mythbusters but alas the series ended before they could get it going.
It's near failure anyway, unless you commit to a full servicing mission a reboost alone won't do much good.
Wouldn't it have been a lot cheaper to launch multiple copies of the Hubble instead of servicing it. We could've had more orbital telescopes like Hubble with more total star watching time if we just launched more of them, sounds like better science to me.
Yes but only if you had used disposable rockets instead of cheap safe reliable reusable Space Shuttles
Lots of Hubbles were launched, but only one was pointed outwards. Currently there are 7 Hubble-class space telescopes in orbit if Wikipedia is to be believed.
https://en.wikipedia.org/wiki/KH-11_KENNEN
Nancy Grace Roman is one one of 2 donated chassis to NASA. Oddly enough, a satellite designed to have a look down makes a great survey telescope looking out. IR mostly. Will be a good companion to JWST at L2.
2028 sounds like a death sentence for Hubble
If 2028 is the deadline, the US won't have a pro-science administration in time.
NASA budget will be spent with SpaceX or some other friend of Trump who can grift off it. The Trump administration's space agenda is all about showing off. Hard science doesn't register as a priority. The administration doesn't give a damn about one of the most successful scientific instruments in human history, because that's science, not a press release for politicians to tweet about.
Hubble doesn't meet those criteria.
The administration has already announced it will squander tens of billions going back to the moon, mostly for show, with few (if any) hard scientific objectives.