I don't understand
It's not being sent into a parking orbit;
It has no reaction material left;
It seems harmless.
So why send commands to shut it down? Cui Bono?
NASA has announced the Kepler Space Telescope has almost exhausted its fuel supply. News of the observatory's decline is expected: it was launched in 2009 and expected to last three-and-a-half years. It's still working today, even though the second of two “reaction wheels” used to aim the telescope broke in 2013. In its K2 …
Because while the craft itself will last indefinitely, it costs money to run the project.
Money that der orange eminenz would rather use to
line the pockets of his friends pay for other things. Big, beautiful walls (that Mexicans will just cut through with a sawzall or blow big, beautiful holes in with ANFO) don't pay for themselves you know.
To stop spurious radio transmissions coming from a defunct and unused craft. To stop it trying to align itself when it can't (possible side effects of that including rapid self disassembly) and as said, to put a definitive end to the mission and close the earth side mission expenses.
Have a gander at what he's trumpeting above: http://fauxscienceslayer.com/pdf/Apollo_Questions.pdf
The first page alone drops the jaw: reproduces the NASA info sheet on Saturn V/Apollo staging but manages to completely misunderstand it ("assume that the 340,000 gallons of stage two are all that was needed to escape Earth’s gravity") when NASA make it abundantly clear that Earth orbit is only reached after 140s of third stage burn. Problems promptly go beyond reading comprehension as he truly doesn't understand that the discarded parts of a rocket don't need to be decelerated ("Therefore to land and take off, the Lunar Lander would have required at least 1/3 of stage two volume, or 110,000 gallons of fuel"). That's precisely the point of both staging and specifically the Lunar Orbit Rendezvous design of leaving as much mass in lunar orbit as possible (command + service modules + one dude). Second page has fewer words but even sillier claims.
So go on, flabber your ghasts on whatever else Fauxy co[oc]ks up. And Faux/Joseph: are you for real or are you doing a Buster Keaton-grade deadpan troll?
" leaving as much mass in lunar orbit as possible (command + service modules + one dude"
How many dudes in the end are still left in orbit around the moon now? And did they have to draw lots, or did the commander pick whichever of the other two dudes was coming home, and which wasn't?
...yeah, okay, deliberate or incompetent misunderstanding is what you're arguing AGAINST.
Such important spacecraft, specifically those that are life-limited by such fuel stores, should be equipped with a refueling port. "But why?", you ask. Because with people like Musk let loose upon the Earth, they're unexpectedly capable of pushing past the existing boundaries.
Perhaps a Kepler refueling contract to SpaceX (payable only upon success) would have allowed them to also include a 'Hail Mary' Kepler Refueling Mission along with their old Tesla Roadster on the otherwise toss-away Falcon Heavy test launch. It might have lined-up perfectly, had anyone connected the then present and future dots so many years before.
This circumstance certainly wasn't very obvious back then, but the larger lesson should be brought forward for next time... Plan Ahead, even for the Unplanned.
1. It probably has one
2. Getting to it in its current location is a major mission. It is not like the Hubble servicing of old performed by the space shuttle. You will need to build a spacecraft especially for this purpose, validate it and launch it.
It's done great but it is done. No fuel and parts breaking. It might be appealing to save this to keep it going but that's just taking resources away form the next mission which might do 20x what Kepler has done.
Pints for the boffins involved for work well done and we look forward to the next bit of epic boffinry.
"2. Getting to it in its current location is a major mission. It is not like the Hubble servicing [in Low Earth Orbit]..."
That's why I specifically referred to the recent SpaceX Falcon 9 Heavy launch which was used only to fling an old sports car towards Mars.
Your point about the distance to the Lagrange point is valid, but it was precisely anticipated and effectively addressed in advance !!
A Kepler refueling probe could have hitched a free ride, assuming that the Tesla could be flung in the suitable direction. Thus dropping the total cost to refuel Kepler to the mid-$xxM range. At least an order of magnitude cheaper than would be expected.
A missed opportunity.
It's usually better to launch a new satellite than refuel an old one. Refueling is quite hard. If you need a human to do it, well, Falcon Heavy is not man-rated and never will be, and BFS will need to be refueled itself before it can reach such a high orbit. If you want to do it without humans, then you need automated docking and other infrastructure that wasn't/isn't available and which adds weight and cost.
By the time they need refueling, the satellites are so old that you'd rather replace them with newer technology anyway.
How about this? NASA leases the Kepler to Musk for 20 years at $1 per year. If Musk can get out there and refuel it he gets the rights to all the Kepler's output for the 20 year period, not to mention even more fame, more validation for SpaceX, and geek cred out the wazoo.
Note, the fuel on board is only for manoeuvring and not the overall operation. So, the scope can continue to function indefinitely, it just can't manoeuvre. Maybe the question should be, what is the most interesting part of space to point at before the thrusters die? So we can at least continue to study that area.
So, the scope can continue to function indefinitely, it just can't manoeuvre. Maybe the question should be, what is the most interesting part of space to point at before the thrusters die?
The disappointing follow-up question being, "And how would you hold that aim point without fuel and reaction wheels?"
Unfortunately, Kepler is already on a reduced-function mission, the K2 or Second Light mission. The K2 mission came about because of the failure of 2 of 4 reaction wheels on Kepler (in 2012 and 2013, respectively). K2 depends on some clever solar sailing, at least in the sense of preventing light pressure from disturbing Kepler's aim while it makes months-long "viewing campaigns" of certain areas of the sky.
Under the K2 mission, Kepler's view changes through the year due to its rotational inertia, light pressure, and need to avoid letting sunlight directly down its telescopic throat. This period of reduced function still depends on the reaction wheels and fuel as Kepler must be periodically rotated. (See link above for a diagram.) Lose another wheel or run out of gas and you lose aiming control, at least partly due to the inability to fight sunlight pressure.
So, when you aim Kepler into the Great Beyond for its hypothetical fuel-free K3 mission, it's not going to hold that aim for long. Not even months.
Looks like we are heading towards the end of what has been a fabulous ride.
It shows the level of engineering that goes into these things when they are able to out-perform their original mission parameters by such an extent.
I guess it goes to show that running out of fuel must have been one of the lowest risks for the project for it to have finally come to that.
I haven't checked the satelite's configuration but considering it's proximity to the sun, electricity will probably be provided by solar panels.
In space, running out of fuel means that you're run out of mass to prove Newton's third law right. This is why EM drives and various reactionless drives are simultaneously desirable and inevitably designed to try and exploit a loophole in the laws of physics.
...because it's not orbiting Earth in the first place. While this is implied in the article, mentioning it explicitly up-front instead of deceptively throwing about a number that's meant to be referenced to the Sun, not the Earth which would be the default assumption of any casual reader, would have gone a long way towards not giving the mother of all headaches to anyone reading who isn't working at NORAD.
Not being snarky: in a world of increasingly bad news thanks largely to the criminals and imbeciles who seem to get to run things (even in the "democracies" these days) I am personally heartened to know that a tremendously worthwhile scientific endeavour exceeded expectation in every way and has added considerably to human knowledge. Yeah, the money could have been spent on other things, like a couple of Trident missiles—but thank goodness it wasn't. We need to know stuff if we are to survive as a species.
(If anyone cares, my definition of "Feelgood news of the (first) best type" is reading the occasional story where a person has done something selfless, decent and brave.)
Curious, if it is low on fuel why not use that last fuel to bring it back down to earth? Rather than, you know just leaving it floating around in space?
Is there enough fuel to do a controlled de-orbit? If so, why not do it if you know the thing is going to run out of fuel?
If an alien species finds us it'd be "Wow man, look at all these dead objects floating about, doesn't even have power, these guys are creating such a mess! Let's go to a more clean part of space instead, where they don't treat space like a dumping ground!"