Kepler Makes First Exoplanet Discovery After Mission Reboot

astroengine writes NASA's Kepler space telescope has detected its first new extrasolar planet after mission engineers were able to save the mission from a premature death after two of the exoplanet hunter's four stabilizing reaction wheels failed last year. Called "K2," the extended mission arose from an "innovative idea" that appears to have given the prolific telescope a new lease on life. "Last summer, the possibility of a scientifically productive mission for Kepler after its reaction wheel failure in its extended mission was not part of the conversation," said Paul Hertz, NASA's astrophysics division director at the agency's headquarters in Washington D.C. "Today, thanks to an innovative idea and lots of hard work by the NASA and Ball Aerospace team, Kepler may well deliver the first candidates for follow-up study by the James Webb Space Telescope to characterize the atmospheres of distant worlds and search for signatures of life."

Why do these reaction wheels keep failing?

[flowerp]

Isn't there any technology to keep reaction wheel discs floating in a vacuum chamber instead of using mechanical bearings?
How about magnetic suspension and frictionless motor drives? This has to be possible with today's technology.

Christian

Re:

[werepants]

It wasn't 4 years, it is closer to 6. Launched in March '09. Secondly, there was a 3.5 year mission life, which Kepler satisfied. Now, even after sustaining some part failures, it continues to do valuable science. So, in fact, it looks like we've got a system that met all objectives and is working far past its design life - if that is pathetic, what would qualify as a success in your eyes?

Re:

[MouseR]

A bajillion dollars wont work.

You need rubber.

Re:

[K. S. Kyosuke]

That doesn't mean that people aren't trying [slashdot.org], though.

Re:

[PPalmgren]

Magnetic suspension? That sounds quite costly on a power budget, and a lot of these probes have really tight power budgets. Plus, you'd have to build in the ability for it to not get ripped apart during launch, which means overengineering the magnetic suspension just to get it off the ground even though that excess capability will never be used in space. I'd think mechanical reaction wheels would be a cinch to lock in comparison.

I'm probably wrong, but that was my initial gut thoughts on the subject.

Re:

[flowerp]

Well you could secure the wheel using some rectractable bolts during launch. Only when in orbit you retract these bolts and then you turn on your electromagnets.

I found quite a lot of research papers on magnetic suspension of reaction wheels. I really wonder why this isn't mainstream technology yet.

Christian

Re:

[werepants]

Here's the thing. Imagine that you are a mechanical engineer, told to build a reaction wheel system that will have something like a 99% chance of lasting 3.5 years, and do it as cheaply, quickly, and lightly as possible. Are you going to pick an unproven, brand new bearing design that introduces lots of extra complexity, would probably involve a lot of new ($$$) and custom design work, and which require all the testing and validation that is involved to qualify a new technology for spaceflight? For starters

Re:

[Will.Woodhull]

There is such technology. On Earth. In space there are limitations of weight and energy consumption to contend with.

Re:

[werepants]

Kepler was designed with a 3.5 yr mission life. It is now going on its 6th year in space. So it met what it needed to do and is STILL producing science. If they had blown time/money/mass on a fancier reaction wheel system, they might've had to sacrifice science payload, or power margin, or had the project go over schedule and over budget and get cancelled altogether. Not to mention that some other, more critical part could've failed because they would have had to sacrifice margin elsewhere.

Perfect is the en

Re:

[K. S. Kyosuke]

For these missions, though, it's generally desirable for the vehicle to last as much as you can make it. Surely the average scientific return per day from Opportunity is much, much cheaper now that it's been operating for ten years than it would have been had it only worked for the originally planned ninety days.

Re:

[werepants]

Of course, but you can't design for infinite lifespan. You design for the mission, add margin as required, and if it lasts longer, great. Almost always, it does, but this is a probability thing - there's every chance that you could get a 1 in a million, mission ending event on day one - there's no such thing as zero chance of failure. If you design for longer than required, you are spending more money/mass/time than you have to.

The real question is up to the principal investigator and his/her science team i

Re:

[K. S. Kyosuke]

All you're saying is true, but I think we've had enough problems with space-based moving parts (the assorted reaction wheels, Voyager 1 and 2 scan platforms etc.) compared to non-moving parts that finding a reasonable solution to this problem seems like something that everyone could benefit from. If a number of long-distance scientific missions have all the components working with the exception of moving parts, it would appear that moving parts with long lifetimes are the next major problem to solve. Voyage

Re:

[whodunit]

Dude. http://classic.slashdot.org/st... [slashdot.org] You're welcome.

Re:

[JustLikeToSay]

Perhaps they moved from round to square (kilometre array).

We suck as a people

[argStyopa]

Seriously, we do.

The fact that we're finding other PLANETS is now so humdrum that this gets 7 comments, this smells very much like the latter Apollo missions "Oh, we've got guys on the moon again? Zzzz."

If I simply posted something controversial*, like an entire article about how "global warming is bullshit", that would get 300 comments, easily.

*of course, I can't use /. as my personal blog. I'm not Bennett Haselton.

Re:

[kelemvor4]

Seriously, we do.

The fact that we're finding other PLANETS is now so humdrum that this gets 7 comments, this smells very much like the latter Apollo missions "Oh, we've got guys on the moon again? Zzzz."

If I simply posted something controversial*, like an entire article about how "global warming is bullshit", that would get 300 comments, easily.

*of course, I can't use /. as my personal blog. I'm not Bennett Haselton.

More than 1800 exoplanets have been discovered. At some point, finding one more ceases to be big news.

Re:

[green is the enemy]

But this is not just another exoplanet. It's the Kepler spacecraft being back in business. I think that's news-worthy. By looking at many different patches of sky they will detect many more exoplanets. The only downside is that they won't be able to observe each patch very long, so only short period planets would be discovered. That's still lots of valuable scientific data. The way they precision-point this telescope now is also interesting.

Re:

[anonymousJUGGERNAUT]

Hear, hear. This is exciting stuff in my book. I'm very happy Kepler is gathering data again, though still slightly frustrated that it didn't last longer with its full capabilities.

Re:

[Coren22]

I was more interested in how they were able to run with only two wheels, that is more interesting at this point.

It turns out (pun intended) that they use the solar radiation pressure as the third wheel.

Re:

[wonkey_monkey]

If I simply posted something controversial*, like an entire article about how "global warming is bullshit", that would get 300 comments, easily.

That's practically a tautology. Of course you'll get comments if you post something controversial, since those tend to be matters of opinion and everyone's got a different one.

If you post about something that's a plain, simple fact (such as this discovery of yet another exoplanet) there really isn't a lot of room for discussion. 300 "Yes, this is a thing that happened" comments don't contain a lot of information.

The fact that discovering exoplanets has become routine is, in and of itself, awesome, but that

Re:

[WrongMonkey]

So people care more about the planet we're living on and the policies used to govern it more than they care about some dead rocks in space. Is that really so surprising?

And the innovative idea is...

[wonkey_monkey]

Nice bit of click-baiting, failing to mention what the innovative idea actually was:

To maintain stability during its new campaign, mission engineers turned to the sun for help, using the continuous pressure of photons from sunlight to act as a counterbalance.