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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)."
what's the purpose of its mission?
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.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
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]
thank God the internet isn't a human right.
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.
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.
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.