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SOFIA Sees Jupiter's Ancient Heat

Soulskill posted more than 4 years ago | from the but-blanche-and-dorothy-didn't-believe-her dept.

NASA 59

astroengine writes "The flying telescope SOFIA took its maiden flight on Wednesday, and its 'first light' images have already been released. The cool thing about SOFIA is that it flies high enough (integrated inside a converted 747, taking it to an altitude of 41,000 ft) to carry it above 99% of the atmosphere's infrared-absorbing water vapor. This means it can collect 80% of the IR radiation that hits orbital telescopes (like NASA's Spitzer) but without the huge cost of being launched into space. Also, SOFIA is expected to last 20 years, many times the operational lifespan of space missions. Already, SOFIA has returned stunning results, including the observation of heat leaking through Jupiter's clouds, heat that was generated billions of years ago when the gas giant was forming."

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So does it fly.. (0)

Anonymous Coward | more than 4 years ago | (#32397364)

So does it 'fly' at high altitude for 20 years, or orbit?

20 years is "many times"? (1)

fotbr (855184) | more than 4 years ago | (#32397418)

Really? I could swear the hubble has been up for 20 years.

Re:20 years is "many times"? (0)

Anonymous Coward | more than 4 years ago | (#32397488)

Yes it is. Typically a mission last 5-10 years. And service missions are expensive.

Re:20 years is "many times"? (4, Informative)

mrsquid0 (1335303) | more than 4 years ago | (#32397612)

Also, infrared instruments usually need to be actively cooled, which means that the spacecraft needs a supply of coolant, such as liquid nitrogen. The coolant usually runs out long before anything on the spacecraft breaks down. So, the lifespans of space-based infrared telescopes tend to be limited by the amount of coolant that can be stored onboard. Sofia does not have that problem because it can refill its tanks every time it finished flying.

Re:20 years is "many times"? (1)

WalksOnDirt (704461) | more than 4 years ago | (#32399214)

Also, infrared instruments usually need to be actively cooled...

It's pretty cold in space. The James Webb telescope will operate at 40 K with just a sun shield.

Re:20 years is "many times"? (3, Informative)

corbettw (214229) | more than 4 years ago | (#32399316)

No, it's not. If you're in view of the sun it's incredibly hot. And even when it's cold there's no medium to absorb your waste heat. In the same way that water cools you faster than air because water is denser, a void won't cool you at all beyond what you can naturally radiate away.

Re:20 years is "many times"? (1)

WalksOnDirt (704461) | more than 4 years ago | (#32400288)

I was explicitly talking about not being in view of the Sun, because of a sunshield. You are naturally radiating away to a very cold sink. Without exposure to the Sun it will get very cold, although at the Earth's distance from the Sun I expect there is some minor back radiation from the Sun's extended atmosphere, plus some conduction from those thin gases. Anyhow, the James Webb is supposed to be at 40 K, which I consider cold, even if perhaps not as cold as SOFIA will be.

Re:20 years is "many times"? (1, Informative)

corbettw (214229) | more than 4 years ago | (#32402790)

It doesn't matter how cold it is if there's no medium to suck up your heat. Again, there's a reason 80F air feels warmer than 80F water: water is thicker and so transmits radiation (eg, heat) more efficiently. A void won't transmit any heat at all, unless you're pushing it out.

Re:20 years is "many times"? (1)

WalksOnDirt (704461) | more than 4 years ago | (#32403070)

A void won't transmit any heat at all, unless you're pushing it out.

What? How do you think the Sun's heat gets to Earth through the void? The only "pushing" the Sun is doing is being hotter than the Earth, just as the James Webb telescope is hotter than deep space, which if you're far enough out to get beyond local effects is at about 3 K.

Re:20 years is "many times"? (2, Insightful)

MrZilla (682337) | more than 4 years ago | (#32404258)

The Sun is throwing photons at us, which is how both light and heat get's here.

And that is the problem. Yes, things in space will cool down, however, the only way this occurs is through what is called "black body radiation", that is, the emission of photons. Cooling down this way is slower than being cooled by air, water or some other substance.

Re:20 years is "many times"? (1)

Romancer (19668) | more than 4 years ago | (#32403846)

A void won't transmit any heat at all, unless you're pushing it out.

So you have an explination on why the "day" side of the moon is about 390 k and the "night" side is around 100 k then?
You think it magically heats up and then cools down for no reason? By your reasoning wouldn't everything that gets any sunlight just keep heating up in space as long as it's in the light? That's ignoring the part about the sun actually being able to heat up things through a void in the first place though. Right?

Re:20 years is "many times"? (1)

corbettw (214229) | more than 4 years ago | (#32408140)

Read the other response down below, from MrZilla. His contains a great explanation for how this happens.

Re:20 years is "many times"? (0)

Anonymous Coward | more than 4 years ago | (#32400032)

Space isn't hot, it isn't cold. It's a vacuum, like your Thermos for your drinks. A completely different set of rules applies in space, which you may not understand right away since you are so used to being immersed in air your entire life. Basically there is no convection in space, and nothing to have a temperature.

Re:20 years is "many times"? (1)

mrsquid0 (1335303) | more than 4 years ago | (#32402044)

The temperature of space is 2.7 kelvin, the temperature of the cosmic microwave background radiation. Getting the temperature below that would require some form of active cooling.

Re:20 years is "many times"? (1)

Unordained (262962) | more than 4 years ago | (#32403022)

Yes. The universe is actively only supplying 2.7 kelvin to your space-borne object -- so it's not being heated much. However said object carries heat with it from its home on Earth, and cannot shed that heat very quickly. In a few years, centuries, maybe millenia, it will finally manage to slowly bleed away the excess heat via radiation only, not convection, and reach 2.7 kelvin. Maybe.

Re:20 years is "many times"? (3, Informative)

AliasMarlowe (1042386) | more than 4 years ago | (#32397644)

I could swear the hubble has been up for 20 years.

Indeed. But Hubble's optics and instruments are optimized for operating in the near-ultraviolet and visible ranges. The more recent Spitzer telescope operates in infra-red (3 micron to 180 micron), so it is a more salient comparison. Spitzer's operational life is limited by its coolant supply of 360 liters of liquid helium http://www.spitzer.caltech.edu/technology/cryostat.shtml [caltech.edu] , unlike Hubble, which does not need cryogenics.

Re:20 years is "many times"? (1)

wwphx (225607) | more than 4 years ago | (#32406400)

Hubble has been up for 20 and a month, though it took 3+ years to fix the aberrant lens so it could produce good science. It's currently planned to maintain operations for at least another 3 years. Personally I hope it's kept in service until the last gyro dies, THEN they attach the booster to de-orbit it. It would be a beautiful thing if they could actually capture it and return it to Earth to be placed in the Smithsonian when it hits end of life, but that's not going to happen.

The Hubble can operate, more or less, 24/7, while SOFIA is limited to the flight hours available on its 747. I would love to see a breakdown of the operating costs comparing Hubble and SOFIA: ignore construction and launch, just how much per hour (which would have to include the 747 maintenance) each costs. Hubble has more ground crew, but there is no cost currently for it to operate.

My wife operates a 3.5 meter telescopes with a variety of instruments available to it. Operating costs are estimated at about $1,000 an hour.

Re:20 years is "many times"? (3, Interesting)

masterwit (1800118) | more than 4 years ago | (#32397716)

Yes, for all the bad press NASA may have received in its past, there have been at least a few outstanding feats achieved by the program, the Hubble being one of these.

In 1990 the Hubble space telescope was launched and put successfully into orbit, and with a few extremely successful "service missions" has allowed us insight to the universe in many ways we might have not seen otherwise (at least for a while!): We have gained understanding how are universe is expanding and the rate at which it is expanding largely due to the contributions of the telescope, we have established the presence (observable!) of black holes, and much more!

To really answer your question however and reiterate the AC's comment on a mission's length, you just don't plan for those type of life-cycles - yes every hardware piece's MTBF may be long, but when averaged together, honestly a car analogy will do best: after 200,000 miles in the vehicle, it usually makes sense to just get a new car instead of deal with the innumerable repairs.

Continuous operation (0)

Anonymous Coward | more than 4 years ago | (#32399168)

And it is not 20 years of continuous operation, it is "two to three times a week for the next 20 years" (from the Discovery.com article). This is 28%-43% of the time
5.6-8.6 years of continuous operation. Plus there are the infrared camera plus "seven other instruments" which means that each instrument may only get 1/8th of the flight time.

While an interesting project, crowing about the 20 year life is not a selling point.

Vibration isolation (4, Informative)

Krishnoid (984597) | more than 4 years ago | (#32397420)

I heard about this a while back [nasa.gov] and am still puzzled as to how you isolate a space telescope from vibrations while its still somewhat within the atmosphere. Is there very little or no turbulence at its flight altitude?

Re:Vibration isolation (3, Interesting)

Kjella (173770) | more than 4 years ago | (#32397520)

Well, according to the WP page on clear air turbulence [wikipedia.org] : "Clear air turbulence[1] weather, sometimes colloquially referred to as "air pockets", is the erratic movement of air masses in the absence of any visual cues, such as clouds. Clear-air turbulence is caused when bodies of air moving at widely different speeds meet; at high altitudes of around 7,000-12,000 metres (23,000-39,000 ft)". I guess at 41000 feet this means they pass above most turbulence. Having been aboard some jumbojets I must say they appear very stable under normal flight, you probably need more stabilizers than on the ground but even there it's windy and such.

Re:Vibration isolation (5, Informative)

Anonymous Coward | more than 4 years ago | (#32397808)

The telescope is mounted on a spherical bearing with gyroscopic stabilization and image feedback to correct for drift. This takes care of rotations. For translations, there is a damped spring mechanism holding the whole kaboodle to the support bulkhead (the image doesn't care if the telescope is translated, as it is "inifinitely" far away; however sudden translations can cause the telescope to flex, moving the image plane). And the pilots are very, very skilled at keeping constant and very precise attitudes. It's remarkably stable.

Re:Vibration isolation (1)

2Y9D57 (988210) | more than 4 years ago | (#32398270)

The telescope was designed and built under the management of the German Aerospace Center [www.dlr.de] with funding from the German Federal Ministry of Economics and Technology (Bundesministerium für Wirtschaft und Technologie; BMWi).

Re:Vibration isolation (0)

Anonymous Coward | more than 4 years ago | (#32402432)

And you know the Germans make good stuff.

Re:Vibration isolation (0)

pyronordicman (1639489) | more than 4 years ago | (#32398334)

Vibration still does reduce image quality. If SOPHIA had been completed on its initial timeline, it would have been more impressive, but modern adaptive optics http://en.wikipedia.org/wiki/Adaptive_optics [wikipedia.org] and large, ground-based telescopes http://en.wikipedia.org/wiki/Large_Binocular_Telescope [wikipedia.org] have made SOPHIA's altitude less of an advantage.

Re:Vibration isolation (3, Insightful)

Daniel Dvorkin (106857) | more than 4 years ago | (#32398944)

Adaptive optics can deal with atmospheric image distortion, but they can't do anything about absorption. As I understand it, the key advantage of SOFIA (and space telescopes, of course) is that it can pick up wavelengths that are absorbed before reaching ground level.

youtube (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32397610)

Thank you for informing us.
youtube [polistube.com]

Cheaper astronomy (3, Interesting)

videoBuff (1043512) | more than 4 years ago | (#32397444)

IT never fails to amaze me that NASA does not send a balloon to 100,000 feet and load it up with all kinds of scientific equipment. That way, they would have advantages of being almost in space, but for a fraction of the cost of sending anything in space.

Re:Cheaper astronomy (1)

DaMattster (977781) | more than 4 years ago | (#32397560)

Untill the balloon goes "pop" ... LOL!

Re:Cheaper astronomy (3, Informative)

Anonymous Coward | more than 4 years ago | (#32397576)

IT never fails to amaze me that NASA does not send a balloon to 100,000 feet and load it up with all kinds of scientific equipment. That way, they would have advantages of being almost in space, but for a fraction of the cost of sending anything in space.

They do. Sometimes they break. [space.com]

Re:Cheaper astronomy (4, Insightful)

Anonymous Coward | more than 4 years ago | (#32397594)

IT never fails to amaze me that NASA does not send a balloon to 100,000 feet and load it up with all kinds of scientific equipment.

With that large payload you'd need a balloon the size of Milwaukee.

Re:Cheaper astronomy (3, Funny)

Sir_Lewk (967686) | more than 4 years ago | (#32399744)

I'm not familiar with the size of Milwaukee, can I get that in football-fields?

Re:Cheaper astronomy (1)

StikyPad (445176) | more than 4 years ago | (#32438508)

American or European?

Re:Cheaper astronomy (0)

Anonymous Coward | more than 4 years ago | (#32458434)

I'm not familiar with the size of Milwaukee, can I get that in football-fields?

The city of Milwaukee [wikipedia.org] proper (i.e. not counting the metropolitan area including smaller communities like Greenfield, Racine, and Waukesha) is 96.9 sq mi (251.7 km2), and an American football field is 0.00619834711 sq mi (0.00535336 km2). Therefore, the size of the City of Milwaukee approximately equals 15633 American football fields.

And yes I had a few minutes to kill...

Re:Cheaper astronomy (1)

mrsquid0 (1335303) | more than 4 years ago | (#32397630)

NASA launches several balloon missions every year. They are cheaper than space telescopes, but they have some severe limitations, such as very short life spans and size-mass restrictions. Sometimes you get more science per dollar spent by flying a telescope in space.

Re:Cheaper astronomy (4, Informative)

DesertNomad (885798) | more than 4 years ago | (#32397898)

Um, they do and do so regularly. http://www.csbf.nasa.gov/ [nasa.gov] http://astrophysics.gsfc.nasa.gov/balloon/ [nasa.gov] Balloons hoisting 2000kg+ payloads, up for weeks at a time, at elevations over 30-35km. When working in the 90's at JPL in Southern California, I would occasionally have lunch with a guy responsible for launching huge skids of scientific equipment at Palastine, TX, at the National Balloon Facility. Palastine is convenient due to the large amount of helium produced as a waste product from the wells in the area. Palastine's accomplishments notwithstanding, Southern California is also home to cutting-edge balloon experimenters. http://en.wikipedia.org/wiki/Larry_Walters [wikipedia.org]

Re:Cheaper astronomy (1)

NixieBunny (859050) | more than 4 years ago | (#32404142)

They do. The folks in the lab next to my office just built such a receiver.

Assertions Without Proof (-1, Troll)

Anonymous Coward | more than 4 years ago | (#32397624)

heat that was generated billions of years ago when the gas giant was forming

Prove that. Don't tell me it's what a theory says, prove that this is the case. Otherwise, instead of stating it as fact explain that it is according to theory and has not been confirmed.

For example, that same set of theories says that stars form from gravitationally collapsing clouds of hydrogen and other gases. They have an accretion disk of dust and other debris that later forms the planets around them. One problem, and it's a gigantic glaring one: the angular momentum would halt the gravitational collapse after a certain point. That point is far before you would ever achieve thermonuclear fusion.

For some reason astronomy and cosmology are full of "statements of fact" that aren't factual at all. Personally I am attracted to the alternative Electric Universe theory because they recognize a need to back up their statements with laboratory experiments and with theories that do have a great deal of proof behind them, such as the behavior of plasma. Oh, and the "magnetohydrodynamics" currently in use by astronomers has already been falsified because you cannot "freeze" magnetic field lines in plasma, nor are magnetic field lines something that can "break" and "reconnect", nor can you have magnetism in plasma without an electric current. Mention these things in any scientific forum and you get shouted down rather than answered with proof, which smacks of religious belief and is entirely unimpressive.

Re:Assertions Without Proof (0)

Anonymous Coward | more than 4 years ago | (#32397770)

AC flame-bait, DON'T feed that troll...

Re:Assertions Without Proof (0)

Anonymous Coward | more than 4 years ago | (#32397896)

AC flame-bait, DON'T feed that troll...

Asking for scientific evidence to back up an assertion that was made as factual is flame-bait? Really? I thought this was science, not religion.

You're demonstrating the very mentality GP talked about. "Oh no, he questions the mainstream, what a troll he must be!" Such a "troll" can be silenced easily enough: give him evidence. You won't. What am I supposed to think, except that this is a religion that uses scientific language?

Re:Assertions Without Proof (1)

siride (974284) | more than 4 years ago | (#32397950)

First of all, this is a news article, not a research paper, so it doesn't need to provide evidence for something that isn't even primary to the article in the first place. Secondly, the OP spent much of the rest of his/her post referencing an alternative theory of the universe that has not been supported by evidence and certainly doesn't compete with the current models. His post reeks of the same kind of persecutionism that bullshit artists typically use when those who know what they are talking about call them out on their bullshit.

Re: Shit I fed him. (0)

Anonymous Coward | more than 4 years ago | (#32398034)

I feel bad posting this as I agree that this may be considered feeding a troll, but honestly, in the future phrase your arguments without such an arrogance.

For some reason astronomy and cosmology are full of "statements of fact" that aren't factual at all.

Using statements like these, people that might have loved to talk with you, or even have an intelligent debate, are turned off when you say "screw your field" up front. This is Talking To People 101. Lastly,

"Oh no, he questions the mainstream, what a troll he must be!"

We do not think you are a troll, question the mainstream, ask questions politely and specifically presenting your facts up front: this is how scientific discoveries are made! But if I am going to refute a mathematical proof of a colleague, I present evidence, I do not just say "this has been proven wrong"!

Don't stoop to the level of Scientology - provide links, citations, and an open mind.

Re: Shit I fed him. (0)

Anonymous Coward | more than 4 years ago | (#32399198)

You post makes a good example of why I'm always saying that "science is the new religion."

Re: Shit I fed him. (0)

Anonymous Coward | more than 4 years ago | (#32401508)

Sounds like you have yourself a religion there too, pal. Repeating the same thing always? Methinks you're not quite as clever as you think yourself to be... Any friends in real life? Pets?
And no joke, the captcha is "pathetic"...

EU is all about no proof and ignoring experiment (3, Insightful)

Chris Burke (6130) | more than 4 years ago | (#32398324)

Personally I am attracted to the alternative Electric Universe theory because they recognize a need to back up their statements with laboratory experiments, and with theories that do have a great deal of proof behind them, such as the behavior of plasma.

LOL.

Electric Universe holds that the solar wind is caused by the sun's electric charge, creating a current of protons outward.

Actual experiment indicates that the solar wind is comprised of roughly equal amounts of protons and electrons traveling outward from the sun. With no net movement of charge there is no current, and Coulomb's Law says an electric field cannot move oppositely charged particles in the same direction, both indicating (though it's really one thing, the Theory of Electromagnetism) that the Sun has no net charge.

As one would expect from the well-verified theory of plasma behavior, the majority of which are quasi-neutral, with those that aren't being necessarily non-dense.

So, yeah, they ignore experiments that prove their most basic premises wrong, and don't even understand the well-established theory their ideas are allegedly based on.

But hey, I can't tell you who you should be attracted to.

20 years? Hubble's done that (1)

petes_PoV (912422) | more than 4 years ago | (#32397640)

Hubble was launched in 1990 so it's managed the 20 years that's "many times the operational lifespan of space missions". Plus it's able to observe 24*7, not just when the crew are allowed to fly. So it does sound like the description could do with reigning in it's dismissive attitude towards the competition.

It obviously does have advantages so far as costs go, though only time will tell just how many observing hours it clocks up

Re:20 years? Hubble's done that (1)

imsabbel (611519) | more than 4 years ago | (#32397952)

Well, hubble had a few repair missions, each of which was A LOT more expensive than this whole project.

Re:20 years? Hubble's done that (0)

Anonymous Coward | more than 4 years ago | (#32402714)

Not to mention that a lot of the X-ray, IR, gamma-ray etc telescopes are put in orbits which are not readily accessible for a repair mission.

Golden Girls! (0)

Anonymous Coward | more than 4 years ago | (#32397994)

Thank you for being a friend
Traveled down the road and back again
Your heart is true you're a pal and a cosmonaut.

And if you through a party
Invited everyone you ever knew
You would see the biggest gift would be from me
And the card attached would say thank you for being a friend.

Where is Spitzer now? (0)

Anonymous Coward | more than 4 years ago | (#32398036)

It's anybody's guess - since the tracking software crashed :-)

http://spitzer.caltech.edu/mission/where_is_spitzer

Jupiter's Ancient Heat (0)

Anonymous Coward | more than 4 years ago | (#32398440)

Good name for a Peter Gabriel single.

It's the potential energy that's old (1)

mbone (558574) | more than 4 years ago | (#32398844)

Jupiter's heat is not billions of years old - the planet keeps shrinking, and thus keeps producing heat.

why not mount the scope towards the front? (0)

Anonymous Coward | more than 4 years ago | (#32399400)

It seems the scope is at the rear of the plane, unpressurized, and the front of the plane is pressurized and has the science area.

Why not reverse that? In the front of a 747 there is a LOT more room due to the expanded fuselage. Why didn't they put the science area in the back, where you don't need that much space for small people and instruments, and put the scope in the larger area in front so you wouldn't be quite so space constrained? Anybody know? I'm sure there is a good reason, I just don't see it.

Why Not Put It on a U-2? (1)

krsmav (1410223) | more than 4 years ago | (#32400242)

The U-2 can reach 70,000 feet, compared with the 474's 40,000. http://en.wikipedia.org/wiki/Lockheed_U-2 [wikipedia.org] There should be U-2s available now that they've been retired. Assuming it has enough payload capacity to carry the SOFIA, more resolution would be available.

Re:Why Not Put It on a U-2? (0)

Anonymous Coward | more than 4 years ago | (#32400806)

Probably because it's a much smaller plane, and it couldn't carry anything of that size. The U2 payload is basically just fuel and pilot.

Re:Why Not Put It on a U-2? (1)

Rent A Ham (865093) | more than 4 years ago | (#32400898)

At those altitudes, the U-2 barely has enough lift to carry it's own weight, let alone carry a telescope with liquid cooling system.

Another reason for choosing a 747 is the size of the telescope. It's roughly half a U-2 long, and more than double as wide.

Re:Why Not Put It on a U-2? (0)

Anonymous Coward | more than 4 years ago | (#32402156)

Those dimensions don't sound right. There is a U-2 (well, ER-2) stationed in the same hangar as SOFIA. It's a DINKY plane. It's barely wide enough for one pilot, let alone a telescope operations team and a navigator (quite necessary due to the complexities of SOFIA flight plans -- no FMS in the universe handles cycloidal flight segments).

To a very good approximation, a U-2 is an engine and wings. Everything else (including landing gear!) is an afterthought.

CO2 versus H20? (0, Offtopic)

Glock27 (446276) | more than 4 years ago | (#32400556)

So, CO2 is now (however wrongheadedly) officially a "pollutant". How is it that water vapor, a much stronger greenhouse gas, isn't considered such?

If you think human produced water vapor isn't an issue, I suggest you research the historical humidity record in erstwhile dry spots like Phoenix, AZ and inland southern CA.

The true answer is neither is a pollutant, and the human contribution to any warming of the Earth is negligible. The odds favor a cooling trend for a few decades regardless.

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