New Spacecraft Set For Dangerous Jupiter Trip

solaGratia passes along word of the equipping of Juno, the most heavily armored craft ever to be launched to another planet. The launch is scheduled for a year from now. "In a specially filtered cleanroom in Denver, where Juno is being assembled, engineers recently added a unique protective shield around its sensitive electronics. ... 'For the 15 months Juno orbits Jupiter, the spacecraft will have to withstand the equivalent of more than 100 million dental X-rays,' said... Juno's radiation control manager... [The] titanium box — about the size of an SUV's trunk — encloses Juno's command and data handling box..., power and data distribution unit..., and about 20 other electronic assemblies. The whole vault weighs about 200 kilograms (500 pounds)."

Comments

why?

[Asaf.Zamir]

what's the purpose of its mission?

Re:why?

[Anonymous Coward]

To look for the monolith of course.

Re:why?

[QuantumG]

to study the planet's composition, gravity field, magnetic field, and polar magnetosphere. Juno will also search for clues about how Jupiter formed, including whether the planet has a rocky core, the amount of water present within the deep atmosphere, and how the mass is distributed within the planet. Juno will also study Jupiter's deep winds, which can reach speeds of 600 km/h.

http://en.wikipedia.org/wiki/Juno_(spacecraft)

Re:why?

[kurokame]

what's the purpose of its mission?

Wikipedia say:

The spacecraft will be placed in a polar orbit to study the planet's composition, gravity field, magnetic field, and polar magnetosphere. Juno will also search for clues about how Jupiter formed, including whether the planet has a rocky core, the amount of water present within the deep atmosphere, and how the mass is distributed within the planet. Juno will also study Jupiter's deep winds, which can reach speeds of 600 km/h.

As to the big "why" as in "why this instead of spending money on something else"...Jupiter is the big laboratory in our solar system. Studying it lets us lets us collect data which will help us study places where terrestrial data alone leaves things a bit fuzzy. It helps us verify the models we're already relying upon. We can make some guesses based solely on what we can observe from Earth - some extremely good guesses. But Jupiter is the big checksum in the sky. Is our understanding of the behavior of the Earth's magnetic field correct? Do our existing models hold up well for a stronger field? Do all these weird patterns we see on the surface of Jupiter and the predictions and assumptions we've made about the forces driving them hold up if we take a lot of new data from a closer vantage point? Are our assumptions about the formation of the solar system valid - and thus most of the assumptions we start with when examining more distant objects?

If you're the kind of person who can't see the value in something which doesn't directly translate into new gadgets - where do you think the technology in the cell phone (or replacement device) you'll own 20 years from now is going to come from? New technological developments are predicated upon basic scientific research. Sure, you can come up with rocks and fire and a few other nice toys without understanding why they work. Maybe god did it, or a wizard, who knows. But modern technology doesn't really work that way, it's far too complicated. Your computer is based upon a number of scientists and engineers understanding what's going on in terms of quantum mechanics, solid state physics, chemistry...not to mention loads of math. You wouldn't be online to question this without people doing basic scientific research.

Besides, the best and most human reason to go is because it's there. How could we not?

SUV's trunk...

[Wyatt Earp]

An SUV doesn't have a trunk.

Re:SUV's trunk...

[Martin Blank]

It does when an elephant is driving.

Re:SUV's trunk...

[SheeEttin]

Heh... reminds me of a joke.

How many elephants can you fit in a Volkswagen Beetle?
Four. Two in the front, two in the back.

...which is the set-up to the real joke:

How can you tell when there's an elephant in your fridge?
- There's elephant prints in the butter.
How can you tell when there's TWO elephants in your fridge?
- There's two sets of prints in the butter.
How can you tell when there's THREE elephants in your fridge?
- The door won't close.
How can you tell when there's FOUR elephants in your fridge?
- There's a Volkswagen Beetle in your driveway.

SUV trunks?

[Mr. Freeman]

Has the US population degraded to the point that we can't figure out what a square meter is? Do we need to measure volume in terms of SUV trunks?

I'll forgive people for not being familiar for units of radiation exposure because it's not something that 99% of the population will ever deal with, but how the hell does a dental x-ray put it in perspective? It's not like you can feel an X-ray. (If you can feel radiation then it's way more than enough to kill you, below insta-death levels you're not going to feel a damn thing).

At least with the size of the thing they gave dimensions in addition to their bullshit comparison, they didn't even bother to mention with real units how much radiation this thing will have to withstand. This serves to do nothing but perpetuate the idiocy growing more and more common in the US today.

Re:SUV trunks?

[oliverthered]

I suppose they could have used 2 hours in a microwave or 40 years under a tanning lamp. But then the radiation may well be x-rays (though they say they tested using a gamer ray source).

It may have been better to put it in terms of how bright the equivalent aura would be if earth had that much radiation in it's atmosphere.

But the article was written by a dentist who drives an SUV, so I doubt he'd have know about things like that.

Re:SUV trunks?

[loufoque]

Has the US population degraded to the point that we can't figure out what a square meter is? Do we need to measure volume in terms of SUV trunks?

It seems to have degraded to the point of confusing surface and volume.
Volume is in cube meters.

Dangerous to whom?

[davidwr]

I'd say any manned mission has a higher risk of fatalities than this one.

100 million dental X-rays

[R.Mo_Robert]

100 million dental X-rays? Can't we use some standard unit, like Libraries of Congress?

Re:100 million dental X-rays

[dangitman]

Well, in this case it would be Librarians of Congress with tooth decay per fortnight.

Re:100 million dental X-rays

[St.Creed]

Beat me to it :)

But on a more serious note: a dental x-ray can vary between 5 and 170 micro Sievert (source: http://hps.org/hpspublications/articles/dentaldoses.html),
so this could be between 500 and 17000 Sievert. A rather large uncertainty in such a statement. Not that it wouldn't be lethal, since anything over 6 Sievert (acute dosis) is considered lethal (and even 1 Sievert acute will get you radiation poisoning - see Wikipedia).

What's with scaring people about dental X-rays, though? While I appreciate the need for an analogy, couldn't they have come up with a better analogy for this one? Like "equivalent to standing inside Chernobyl starting on the first day of the accident, for 15 months in a row"? (*)

That'd make the picture much clearer, I'd say.

(*) using 20 Sv for Chernobyl first day exposure (max value) and the average value for the potential exposure with the 100 million dental x-rays, which gives 8750 Sievert total exposure.

Re:dangerous?

[Bigjeff5]

Compared to Jupiter, they were a cakewalk.

Do you have any idea the forces that are involved? Jupiter's tidal forces are so strong they may warp its moons enough to generate significant amounts of heat inside its moons - moons that are the size of planets (Ganymede is bigger than Mercury, and nearly as big as Mars).

We're not talking about just orbiting Jupiter either - we've done that before. We're talking going down into low-Jupiter orbit to study it up close and personal like. It's almost 320 times as massive as the Earth, so it's going to be hit with those insane tidal forces. It's also generating incredible amounts of radiation which will easily fry all the electronics on-board.

I mean, for heaven's sake, they've built it out of 500 pounds of titanium to withstand the radiation and crushing gravity. That's not exactly a heavy metal. They'll be ending the mission by diving it into the surface, and they are not even expect it to survive to the surface with all that protection.

Really, we've done nothing like it before.

those are good questions

[circletimessquare]

but from the story summary, i think the most pressing question would be why the heck does jupiter have millions of dental X-rays?

Re:those are good questions

[QuantumG]

Fat planet eats too many sweets.

no, no, no

[circletimessquare]

as we know from 2001/ 2010 a space odyssey, enough black monoliths and jupiter will finally ignite and become a second sun. but the question is: what are those black monoliths? and, we finally have our answer: dental x-ray machines, alien dental x-ray machines. that is what inspired pre-homo sapiens species to begin the journey to modern man: the divine inspiration of advanced dental technology

It's uglier than you can imagine.

[jrst]

It's uglier than you can imagine.

IIRC (sorry, it was long ago)... on the Pioneer 10//F 11/G missions Van Allen spec'd the Geiger Tube Telescope for an order-of-magnitude more than expected, and we pegged them. Pioneer suffered significantly--never regained full range on one channel of the IPP (Imaging Photopolarimeter--that thing that made the pretty pictures possible).

We nearly lost the spacecraft due to some spurious crap/commands during periapsis on Pioneer 10/F. Try dealing with an idiot-savant-brain-damaged-two-year-old throwing a tantrum with ~90-minute round-trip light time at 256-1024bps. It's ugly.

The running joke was... If you want to be absolutely certain a spacecraft is sterile, just make a flyby of Jupiter. Jupiter's belts are not to be taken lightly. A seriously understated quote from one post-mission presentation "Closest approach: It’s hot in there!"

It's not just hot, it's a red-hot-poker enema in your electronic guts. That Pioneer 10/11 F/G--the epitome of cheap deep-space exploration--survived those encounters and lived to tell--and did so for many more years still amazes me.

It is a testament to what we can do, and what deep-space exploration is all about. (So allow me a bit of hubris: Suck eggs Voyager... you had a much bigger budget, you got the press, you got your name in a Star Trek movie, but we were there first. Nah nah nah.)

Re:It's uglier than you can imagine.

[CrashandDie]

Van Allen spec'd the Geiger Tube Telescope

Oh man, I remember that concert, it was just absolutely insane.

Re:It's uglier than you can imagine.

[Jeprey]

Indeed. The illusion of space safety largely comes from the fact that the space shuttle uses only LEO where radiation is only a bit higher than terrestrial (but still higher) and the gullible fantasies of SciFi stories. Get to a higher orbit or deep space and it's radically higher normal radiation levels. The mission profile of Juno is like the Earth's van Allen belts fully charged. Very nasty.

Most commercial semiconductor technology is burned up by the high orbit and deep space radiation levels shortly after being powered up - back in the day we tested off-the-shelf Intel processors and SNL clones of the same and the first small 10KRad dose destroyed the Intel processors dead while the clones (designed from scratch for rad hardness) lasted to MRad doses.

Humans beyond LEO? Don't make me laugh! This is the Achille's Heel of any Mars mission. There is no existing technology that can fix this either. Even the Juno shielding comes at a heavy price: using high Z shielding increases cosmic ray and ion spallation which results in increased total dose that the shielding is nominally trying to reduce - because the process occurs *inside* the shielding material and actually gets worse with Z, it's a trade-off between bad dose levels and really bad dose levels. That's what is alluded to in the article as well. Strictly there is no way to shield down to human-tolerable levels.

Re:It's uglier than you can imagine.

[kurokame]

Deep space is considerably lower in radiative flux than it is when you're near a star for obvious reasons involving decay times and 1/r^2 laws. If it worked like you're saying, the universe would be extremely bright and extremely hot everywhere. In real life, most of it is just empty.

Also, there's an old trick which pops up in hard SF every now and then. Bury your interstellar ship inside layers of rock or water or both. Get it thick enough and it will shield out damn near anything which you're likely to encounter regardless of where you are or how fast you're going. Of course there are still places you're likely to want to avoid...stellar nurseries are probably not a nice place to be, nor do you want to get too far on the inside of the habitable zone of a star. Stuff like that. But the fun thing about radiation is that you can stop any conceivable level of radiative flux simply by putting enough matter between it and you. So much for "no way" eh?

As for something as simple as sending a probe to Mars - yes, you have to account for radiation in the design. But it's hardly insurmountable. If somehow it mysteriously happens that nothing else works, you can always fall back to covering the hull in water tanks. Higher fuel cost, but certainly possible.

Re:It's uglier than you can imagine.

[loufoque]

Humans beyond LEO? Don't make me laugh! This is the Achille's Heel of any Mars mission. There is no existing technology that can fix this either.

Just make a massive ship; its sheer mass would provide enough shielding.

Obviously, it would have to be built in space. But to make a good enough space or moon base, you'd have to bring fairly massive amounts of material as well. And the only cost-effective ways to do that are propulsion based on nuclear explosions or a space elevator.
One technology people are afraid of, the other is not ready.

Re:It's uglier than you can imagine.

[mbone]

While the depth of the atmosphere also helps in shielding, 14 pounds per square inch (or, ten metric tons per square meter), is not a bad first guess for adequate shielding for most of deep space, although it would not nearly be adequate for Jupiter. (Not every part of the spacecraft would require this, but a shielded "safe room" for solar flares would be a very good idea.) Note that the Jovian / Solar Flare radiation is all charged particles (no X or gamma rays), so it might also be possible to do magnetic shielding.

Re:It's uglier than you can imagine.

[mbone]

There has to be shielding, but not every part of the spacecraft has to be shielded. BTW, NASA does monitor radiation exposure to its astronauts, and you can't do a long duration mission to the ISS once you reach your lifetime limit.

Re:It's uglier than you can imagine.

[MartinSchou]

Also, there's an old trick which pops up in hard SF every now and then. Bury your interstellar ship inside layers of rock or water or both.

One advantage to this is waste management.

Since you'd need to recycle EVERYTHING on an interstellar (or even interplanetary) ship, use the massive radiation to your advantage. Feed the plumbing from all the waste to the outermost layers of the ship, exposing it to as much radiation as possible, thereby killing all bacteria, viruses and other parasites.

Doing this should allow you to save space/mass, since you then don't need as advanced a water treatment plant as you'd otherwise need.

Re:It's uglier than you can imagine.

[Anonymous Coward]

Humans beyond LEO?

well shit, I bet you're the type who thinks the various moon missions were fake as well.

The moon is beyond LEO.

Re:It's uglier than you can imagine.

[DerekLyons]

And the only cost-effective ways to do that are propulsion based on nuclear explosions or a space elevator. One technology people are afraid of, the other is not ready.

One technology people are afraid of, two technologies that are not ready.
 
Seriously, people treat nuclear pulse production as if were a done deal, but there's been damn little actual engineering work accomplished. Exactly none of the equipment has been tested except in the form a non-nuclear (very small) scale model. Huge questions remain about the design of the pusher plate and the shock absorbers, as well as the of pulse unit itself.

USD $700 million, that's practically free.

[oliverthered]

Juno is NASA's newest planned mission to Jupiter. As part of the New Frontiers missions, it will focus on cost-effective research of the planetary giant. The project's costs will not exceed USD $700 million, however, budgetary restrictions have caused the original launch date of June 2009 to be pushed back to August 2011.

Apparently, that's about the same as the US has spent on the war in Iraq (ignoring all the other countries [including Iraq] and the none-financial costs)

http://costofwar.com/

or to put it another way

Due to the secretive nature of Hollywood accounting it is not clear which film currently holds the record as the most expensive film ever made. Some charts have Pirates of the Caribbean: At World's End in the top spot which had an estimated cost of $300 million[1] while others have Spider-Man 3 which was officially acknowledged to cost $258 million.[2] Pirates of the Caribbean: Dead Man's Chest and its sequel Pirates of the Caribbean: At World's End were produced together on a combined budget of $450 million,[3] making it the most expensive production. More recently there have been reports that Avatar is the most expensive film ever made with speculation that it cost $280 million,[4] which if true would make it the most expensive single-film production.

But then there's the 'real' costs too, how much people spend on movies, just like how much they spent on this project.

For instance:
http://en.wikipedia.org/wiki/List_of_highest-grossing_films
1 Avatar 20th Century Fox $2,731,058,342 2009
[# 1]
2 Titanic Paramount Pictures
20th Century Fox $1,843,201,268 1997
[# 2]
3 The Lord of the Rings: The Return of the King New Line Cinema $1,119,110,941 2003
[# 3]
4 Pirates of the Caribbean: Dead Man's Chest Walt Disney Pictures $1,066,179,725 2006
[# 4]
5 Alice in Wonderland Walt Disney Pictures $1,024,291,110 2010
[# 5]
6 The Dark Knight Warner Bros. $1,001,921,825 2008
[# 6]

Re:USD $700 million, that's practically free.

[oliverthered]

Thinking about it, why the hell don't they turn the mission into a Movie (as cost effectively as possible) and then release it to generate a load more review.

I mean, I sat through penguins standing pretty much in one place for over an hour, and that was one of the best things I've seen.

Re:USD $700 million, that's practically free.

[sjames]

You're only off by THREE ORDERS OF MAGNITUDE!

You must be one of those Hollywood Accountants yourself.

opps, out by a factor on 100.

[oliverthered]

Sorry, the cost of war in Iraq (financially to the US alone) is 100 times that of this mission to Jupiter.

Re:opps, out by a factor on 100.

[stevelinton]

Actually it's 1000 times...

Re:opps, out by a factor on 100.

[tsm_sf]

Poe's law (religious fundamentalism) -- "Without a winking smiley or other blatant display of humour, it is impossible to create a parody of fundamentalism that someone won't mistake for the real thing."

Re:dangerous?

[mbone]

You are correct that there are no significant tidal forces in a 10 meter spacecraft, but there are certainly solar tides on the Earth - they are about 1/2 the amplitude of the Lunar tides, and the interaction between the two gives rise to the Spring and Neap tides.

Re:dangerous?

[photonic]

Correct me if I am wrong, but I doubt that tidal forces play any role at all for Juno. Tidal forces are caused by the difference of gravity over the extend of an object, which is only significant for planets and moons which have sizes on the order of thousands of kilometers, compared to satellites with a diameter of 10 meters. According to the last formula found here, the tidal force is roughly a fraction (diameter / orbit height) of the gravitational force itself. A satellite of 10 meters orbiting at the same height above Jupiter as Io (known for its tidal induces volcanoes), will thus experience just a few millionths of the force experienced by Io.

Re:Juno articles still plagued..

[imsabbel]

Its a meassurement with 1 significant digit. Thats a more correct way than the typicel " about 1 inch (2.54cm)" type conversion that implies a higher accuracy in one type of unit

The purpose of the mission

[bugs2squash]

Is to search for the other Juno that was described here. As the first SUV is now several light-library_of_congresses away and could be anywhere within a volume of 10^76 cubic football fields of its projected location.

Re:dangerous?

[sjames]

The free market can sort this out. Given the crazy costs of healthcare in the U.S. these days it won't be long before the uninsured resort to taking a trip to Jupiter to get their teeth X-rayed. If NASA is really nice, they can probably get them to take the space probes with them, especially if they share gas money.