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Hubble Space Telescope Will Last Through the Mid-2020s, Report Says (space.com)
schwit1 shares a report from Space.com: Despite recent issues with one of its instruments, the Hubble Space Telescope is expected to last at least another five years. A new report suggests that the iconic spacecraft has a strong chance of enduring through the mid-2020s. [...] One reason the spacecraft has lasted so long is that astronauts have provided aid. Servicing missions continued to update the telescope until 2009, when the space shuttle was retired. The final update to Hubble included the installation of two brand-new instruments, the Cosmic Origins Spectrograph (COS) and WFC3. The astronauts on Servicing Mission 4 also performed on-site repairs for the telescope's two other instruments, the Advanced Camera for Surveys (ACS) and the Space Telescope Imaging Spectrograph (STIS), both of which had stopped working. The astronauts additionally replaced Hubble's 18-year-old batteries with new ones; installed six new gyroscopes, whose job is turning the telescope; and added a brand-new Fine Guidance System to point the instrument. Astronauts also covered Hubble's equipment bays with insulating panels and installed a device that will help to guide the observatory down when its mission comes to an end.
the Hubble got launched, fixed and repaired and updated and serviced because the US had the Space Shuttle to carry a crew, equipment, parts, space walkers, support, the Canada arm, manoeuvring fuel, a toilet and shower up to the Hubble's high orbit. They don't have a Shuttle any more.
The US plans for a return to manned spaceflight involves 1960s-style "spam in a can" up-around-and-down flights to nowhere, with none of the useful luxuries the Shuttle had, especially the ability to support spacewalks.
the James Webb Space Telescope, (JWST) is currently scheduled for March 2021. It was designed as the successor to the Hubble , and originally scheduled for launch in June 2018.
https://www.nasa.gov/press-rel...
How interesting, a government web site that's still working.
"De-orbiting" costs much less fuel and is a much longer term solution. Reducing its orbital speed even slightly will bring it into more contact with Earth's atmosphere, which will continue to slow its speed until it spirals down: this is the normal fate of every object in LEO, or low earth orbit. The thing is 40 feet long and weighs 22 tons. I find myself wishing it could be salvaged for posterity, like many NASA missions it has vastly exceeded its expected work life and provided unique insights into the nature of the universe.
Gemini "EVA" involved both crew members being suited for space all the time in the capsule since the spacewalks involved depressurising the entire crew living quarters. The Hubble had an airlock, jumpsuited support personnel for the jumpsuited spacewalkers who assisted them into their suits and out again permitting multiple two-man multi-hour spacewalks to accomplish several different tasks on each flight which lasted several days.
The Shuttle also had the Canada arm to carry space walkers and parts to the Hubble as well as grapple with the Hubble itself. Dragon has no arm and nowhere and no way to mount an arm or power and control it.
Dragon is optimised to reach the ISS orbit at about 400km, carrying passengers up and down from the space station. The Hubble orbits at about 550km, a lot higher. To reach the Hubble and manoeuvre around it the Dragon would have to carry more fuel and less payload but still have parts, EVA suits, supplies for an extended flight time of over a week, an airlock etc.
The Shuttle had a large dry mass but it also had a large "wet" mass -- it could launch with up to 18 tonnes of manoeuvering fuel as well as 20 tonnes of payload in the payload bay (there were mass tradeoffs though depending on the mission). Dragon is designed down to meet "spam-in-a-can" specifications, a Soyuz replacement with some extra bells and whistles.
It would be better to build and launch a Hubble replacement rather than attempt to keep it running by repair and maintenance flights. Technology has moved on since the 1980s when the Hubble was designed and built. I doubt if there's a budget for an exact replacement now though.
Hopefully the BFR works; if Ol'Musky gets it flying for anywhere near the projected cost, it would have little issue with recovering Hubble and bringing it down. And for that matter, the BFR would also be capable of hauling up much larger replacement telescopes.
... JWST has an impossibly complicated origami shield for no reason.
There's a reason, a very good reason: JWST is designed to be an infrared telescope, hence it has to be kept at very low temperature, and if you looked around the Inet about JWST, you would find why the shield is this way - it's optimal considering weight needed isolation and price.
Then there is WFIRST ... They were handed a ready made spaceframe that they are familiar with.
WFIRST was designed to be smaller, however about 2011 NRO disclosed having a project of Hubble class spy telescopes (since 1976) and in 2012 donated 2 not needed mirrors, not spaceframes - just optics, which has to be adjusted to look deep out not close down. Since the donated mirrors are bigger than WFIRST design, the telescope had to be redesigned, and considering bigger, heavier and needing bigger launcher ended up more expensive (to be fair: estimations differ, some say otherwise).
Don't get me wrong, I am very happy for the donation, WFIRST will be more capable, however, considering NRO program starting date of 1976 and donation in 2012, it's more likely out of needed storage space for better mirrors than a good heart.
Now that we're nearly a decade past the last shuttle launch, it makes sense to take stock in what the post-shuttle space missions have been like. It seems in a lot of ways we lost a lot of capabilities of near-Earth orbits and have to entirely rely on the ISS for experiments. Satellite and equipment repairs on things like Hubble are now out of our capability and I wonder what we've intangibly lost in terms of science and innovation that went into the shuttle's design and upkeep. I'm probably just being nostalgic for the shuttle since I grew up with it as a constant presence, but I feel like we've taken a step back having to rely on the Russians to launch human missions in the short-term and going back to capsules that are nothing more than taxis rather than being a platform for experiments and equipment launches/repairs.
JWST isn't a true "replacement" for Hubble.
Tthere are a few things JWST can do that Hubble can't, but there are a LOT of things Hubble can do that JWST can't. It's more of a step sideways than a step forward.
As an augment to Hubble, it has the potential to be a fantastic resources. As an outright replacement, it kind of sucks.
Making matters worse, JWST's expected service life is shockingly short, and unlike Hubble, NASA appears to really *mean* it when it says it plans to deorbit JWST on schedule (to avoid leaving spacejunk cluttering a Lagrange point). So it's ENTIRELY conceivable that if Hubble gets deorbited with JWST as an alleged "replacement", we'll end up with no comparable space telescopes AT ALL a couple of years later.
The best thing we can do with Hubble right now is to get maximum use from it, then do our best to keep it cheaply re-boosted until such time as we have the ability to do a proper servicing mission on it (replacing its electronics and mechanically-failing parts, but taking advantage of the huge spaceframe and lens that we realistically have no way to replace anytime within the next 15-25 years).
For somewhat of an analogy, imagine that your family runs a tour service on a remote island in the middle of the Pacific Ocean & has a big, London-style double-decker bus that's iconic and wildly popular with tourists. Your grandfather bought it 30 years ago when it was shiny & new, and had it transported to the island in a semi-custom airplane that no longer exists (assume that for some reason, boats can't reach the island... maybe it's surrounded by jagged reefs that would be suicidal to attempt navigating by boat). Today, that old bus is kind of a hot mess... it needs a new engine, the seats are tattered, and it needs a good paint job. A brand new bus would cost less than refurbishing the old one, except for one problem... there's nobody who's CAPABLE of transporting an entire new bus to your island because it's too big to fit into any of today's smaller, cheaper, safer, and more fuel-efficient (but sadly, smaller) cargo planes, so you have to make do with packing replacement parts onto multiple air cargo planes and flying them in if you want to continue having a working double-decker bus on that island.
It's not a perfect analogy, but it makes the point... Hubble has parts that simply CAN'T be replaced anytime soon. If we throw them away by deorbiting it, the capabilities they represent will be gone "forever" (at least, the foreseeable future, quite probably the remainder of our own lives). A limited robotic servicing mission by SpaceX that does nothing but boost Hubble into a higher orbit to buy us another 10-15 years to decide what to do with it would be an extremely prudent investment, because the alternative would be the destruction of a valuable asset that literally can't be replaced at any cost within the next few years.