NASA's Kepler telescope is sent back to sleep as scientists preserve fuel for the next data dump Kepler’s resurrection from hibernation has been short-lived - NASA has put the veteren space telescope back in sleep mode after it was up and running less than a month ago. The probe, sent to sniff out exoplanets that may be lie in habitable zones around stars, is expected to run out of fuel soon. Launched in March 2009, the …
Refueling Kepler
Wouldn't that be worth the money?
Unlike Hubble, Kepler is not in Low Earth Orbit where it is easily accessible by existing manned vehicles.
Moreover, it's not designed to be refueled, and even if you did refuel it, one of it's thrusters and two of the reaction wheels have failed - so you'd be looking at a deep space overhaul of something which was never designed to be touched post-launch (i.e. lots of tiny fiddly bolts and plugs which are fine for a tech in a clean room but not for a spacewalking astronaut).
It would be cheaper and easier to just build a new telescope with the latest tech and launch that instead.
It would be cheaper and easier to just build a new telescope with the latest tech and launch that instead.
I'm not that sure about that. Kepler cost was $500 millions, TESS is around $200million. If Bezos or Musk can refuel those with unmanned vehicles for let say $50millions, it may be worth the try.
Of course, it's obvious it would be better if the ships were designed to be refueled.
Any manned mission is going to cost a lot more than 50 million. Kepler wasn't designed for in-flight refuelling. That means sending astronauts out there with tools and tanks full of nasty chemicals like Hydrazine. Not to mention replacing the reaction wheels, calibrating the whole 3-ring circus and shaking it down for a test. There's also the question of whether you've got enough delta-V to actually rendezvous with Kepler in a reasonable length of time - which is a much bigger deal on a manned flight using life support supplies than with a robot spacecraft.
Maintenance of craft anywhere but low orbit is a knotty problem because of the time to get a manned mission to rendezvous the target quickly. Fast burns tend to use a lot more delta-V (and therefore fuel) than a maximally efficient orbit. The exponential nature of the rocket equation makes piling delta-V onto a mission get very expensive very quickly. Combine that with the size of a manned payload and you make maintenance in-situ a very expensive proposition. By and large nobody bothers to do it with satellites.
If you want to learn about orbital mechanics then I can't recommend Kerbal Space Program highly enough. You'll not see any better crash course in the practicalities of the subject anywhere - and crash you will.
https://xkcd.com/1356/
>Why do you absolutely want to send a man there to do the job?
Because, unless things have changed since Hubble, making the satellite serviceable means that ever part on it - from the computers controlling the cameras to the data link sending the images back have to be man-rated. Which today means using parts from the Shuttle era.
The advantage of this is that it increase the cost 200-300% and limits you to a handful of suppliers - all owned by Boeing
If Bezos or Musk can refuel those with unmanned vehicles for let say $50millions, it may be worth the try.
Why do you absolutely want to send a man there to do the job? It would be much more expensive and life-threatening. Such an operation should be made by a robotic mean
I know things like this are easy in Star Trek, and fanboys like to think that their heroes can perform miracles in a tenth of the time and for a hundredth of the cost that real engineers would need, but Star Trek is fiction and this stuff is hard. Very hard.
I'm not that sure about that. Kepler cost was $500 millions, TESS is around $200million. If Bezos or Musk can refuel those with unmanned vehicles for let say $50millions, it may be worth the try.
The launch would cost you north of $75m. And that's before you developed your payload (including robot butler to disassemble Kepler). Realistically it's at least a $200m mission.
In 5 years launch costs will (probably) be much lower, but not today.
And refuelling still leaves you with the issue of replacing a bunch of failed components. It is absolutely not worth it compared with spending the money on a new (and better) telescope. Which is what we did (TESS).
Maybe in the future (once the economics and launch costs have fallen, and we have orbital factories/shipyards) we will build modular science platforms which can be easily serviced, refuelled and have reaction wheels replaced. But Kepler is not of that generation.
Orbits there alone, the end is nearing
All systems no go, goodbye there
Control is not convinced
But the computer has the evidence
We need to abort
Hibernation starts
Watching drowsily, the 'scope is certain
Nothing left to chance, all is working
Trying to relax, orbits round the sun
"Send me up a drink", jokes Kepler One
The count goes on
4, 3, 2, 1
Sol below us
Drifting sleeping
Floating weightless
Calling calling home
All the fuel is out, we're now adrift.
Stabilizers off, reactions still
Finished collecting, requested data
What will it effect, when all is done
Thinks Kepler One
Back at ground control, there is a problem
Rouse from hibernation, not responding
Hello Kepler One, are you receiving
Wake your sleep-filled head up, we're standing by
There's no reply
4, 3, 2, 1
Sol below us
Drifting sleeping
Floating weightless
Calling calling home
Across the solar wind
A final message, "use my data well"
Then nothing more
Far beneath the probe, the sun is burning
They don't realize, he's alive
No one understands but Kepler One sleeps
Now the light commands, this is my home
I'm staying home
<repeat chorus>
One for all the scientists who worked on this -->
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