Iconic Planet-Hunting Kepler Telescope Wakes Up, Phones Home

Kepler, which has discovered about 70 percent of the 3,800 known exoplanets to date, woke up from a four-week hibernation yesterday and has begun beaming data home, just as planned, NASA officials announced today. From a report: Kepler had been sleeping in an attempt to save thruster fuel, which is running very low. Mission team members wanted to make sure the spacecraft had enough propellant left to orient its antenna toward Earth for yesterday's data dump. Far-flung NASA spacecraft send information back to mission controllers via the agency's Deep Space Network (DSN), a system of radio dishes around the globe. The sun-orbiting Kepler's latest allotted DSN window opened yesterday, agency officials have said.

Plot twist.

[Anonymous Coward]

Due to Verizon's new data plan, Keplers transmission rate was throttled and then capped for going over the 8gb limit.

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[Applehu Akbar]

Planet hunting results were also de-prioritized and filtered as a potentially blasphemous content...

The filter removes all planets which are white, or which are spherical.

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[sheramil]

Uh... the article says it was the Kepler telescope that phoned home, not the ghost of Hunter S Thompson after huffing ether.

Non-propellent based space travel

[jellomizer]

It is too bad that for space travel there isn't much alternatives to propellant to alter and correct course.
The mars rovers for the most part have well exceeded their design life cycle mostly due to the fact that it is solar powered and uses electric motors for its transpiration. If needed an expendable fuel it would had only lasted its prescribed life cycle.
However good old physics shows that an electric motor may be able to spin and rotate a space craft there isn't much it can do for course, and prevent it from leaving an orbit.

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[Joce640k]

However good old physics shows that an electric motor may be able to spin and rotate a space craft

What do you mean "may"? Doesn't physics tell you things like that for sure?

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[Anonymous Coward]

What about PUSHING a spacecraft? You can spin all you want, you're still slowly falling towards the thing you're orbiting. HST has no propellant to maintain its altitude, so the last part of every servicing mission was to use available propellant on the shuttle to throw it a few more Km back up.

Re:Non-propellent based space travel

[DRJlaw]

However good old physics shows that an electric motor may be able to spin and rotate a space craft [but] there isn't much it can do for course, and prevent it from leaving an orbit.

'However good old physics shows that an electric motor may be able to spin and rotate a space craft..."

What do you mean "may"? Doesn't physics tell you things like that for sure?

What about PUSHING a spacecraft? You can spin all you want, you're still slowly falling towards the thing you're orbiting. HST has no propellant to maintain its altitude, so the last part of every servicing mission was to use available propellant on the shuttle to throw it a few more Km back up.

Good old physics also shows that nothing in the universe is able to force a Slashdot reader to read and comprehend the comments that they are replying to.

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Re: Non-propellent based space travel

[Anonymous Coward]

Control Moment Gyroscopes are great. But they can become saturated (eg, reach maximum spinning speed) at which point angular momentum must be âoedumpedâ using reaction jets â" which require fuel.
https://en.m.wikipedia.org/wiki/Control_moment_gyroscope

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[yes-but-no]

I bet none of these change the CG of the object (space craft, cg center of gravity); To move the CG, you need to push some mass in the opposite side as required by the law of conservation of momentum; and this mass is some fuel burnt and the resulting hot exhaust gases (mass x velocity). motors etc can make some some internal part of the craft spin and likely cause other parts to compensate for (conservation of angular momentum).

Re:Non-propellent based space travel

[Brett Buck]

OY VEY! Kepler has reaction wheels that do exactly as you suggest, as have all similar spacecraft for many decades.

      The problem with Kepler is that the reaction wheel bearings failed on multiple wheels, so they had to use the thrusters exclusively, which it did for a long time now, and now, finally, they are running out.

        Despite that, it was designed for a 3 and a half year mission and it is still functioning after more than 9 years.

        It's really hard to see this as any sort of failure.

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[im_thatoneguy]

Also the reaction wheels sometimes have to be reset due to losses and gimbal lock.

fillerup?

[anon mouse-cow-aard]

Spacex has made getting to orbit cheaper, and it takes a decade to get a satellite in the air. why not schedule a fuel run? https://www.space.com/25259-ro... [space.com]

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[BlueStrat]

You do realize that unlike the Hubble telescope which orbits around the Earth that the Kepler telescope is in an Earth trailing orbit around the sun?

Ask Elon Musk and SpaceX to refuel it.

If there is anyone on the planet that could conceivably accomplish such a feat in a timely manner and on a budget, it would be Musk and SpaceX.

Strat

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[Strider-]

Well, first the probe isn’t designed for refuelling, so actually doing that would be hard.

Secondly, the probe is in deep space, in orbit around the sun, rather than about the earth. At the moment, it’s just a little less than 1AU (the distance between the sun and earth) away from the earth.

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[anon mouse-cow-aard]

OK, but a tesla roadster has been sent to orbit between us and Mars, with a falcon heavy... or worst case, for 2x the price a ULA Atlas.

How much would it cost...

[TomGreenhaw]

... to pay Space-X to refuel it?