Spacecraft Teamwork Ferrets Out Jupiter's Secrets

Judebert writes "Working together, Galileo and Cassini found how the solar wind affects Jupiter, shaping its magnetosphere (the biggest object in the solar system with distinct boundaries) and triggering auroras. They also detected the magnetic footprints of Jupiter's moons in the auroras. The Hubble and Chandra also had a role in this display of inter-planetary teamwork. Of course, the big benefit you receive from your tax dollars is all the pretty pictures! New desktop images for me!"

Re:Why the obsession with magnetic fields?

[pyr0]

Isn't this what science is about though? Learning something new that was previously unknown?

Application of the knowledge about Jupiter's magnetic field might be a different story, although you never know how this might be useful when (and if) we start exploring outside of our planet more and more.

Hard core Geeks

[Lord_Of_The_Beer]

You are complaining that this stuff only matters to hardcore geeks.......

You are in the science pages of slashdot.

Think about it.

Re:Why the obsession with magnetic fields?

[nerdlyone]

Sorry, but naturally occuring magnetic fields aren't very exciting stuff anymore. No one cares about them except the most hardcore geek.

Earth has a naturally occuring magnetic field. It is partially responsible for deflecting harmful particles and radiation from the sun. These particles and radiation cause damage to satellites, both public and private. Understanding other natural magnetic fields may be useful in our own endeavor to understand the earth, and how to protect the hardware we put into orbit--which is not exactly cheap.

I of course don't know that this particular research will be useful in this way, but it is an example, a possibility. It is often hard to determine the benefits that will arise from discovery. But I really don't see how someone typing on a computer can say with a straight face that since this doesn't seem to have an immediate practical application, it is therefore useless. We live in a world shaped by discoveries that, at the time, had no practical applications.

Besides, some of us are hardcore geeks. That's why we're at /. reading on the space forum.

Magnetosphere

[Mr.Intel]

I think it is interesting that the pictures show the magnetosphere is parallel with the planet's rotation. This is opposite from Earth's. Do the magnetic poles of Jupiter then rotate with the planet? Like a giant spinning magnet. Makes for a very diverse magnetic environment for the entire Jovian system.

Whoops

[Mr.Intel]

I read the picture wrong! My bad. I saw the radiation belts and thought they were the magnetic fields. Too bad we can't recind posts...

Re:Magnetosphere

[Nyphur]

Well you have to remember that our magnetic poles also shift. Ours shifts partly because of the iron in the earth shifting.

Re:Magnetosphere

[CheshireCatCO]

Actually, what you said is correct (if not what you meant): Jupiter's magnetic axis is more or less aligned with the spin axis. (It is, in fact, tipped 10 degrees towards 202 degrees System III longitude.) The mangetic field does spin with the planet, just like Earth's. This means that the Galilean moons experience different magnetic fields over the 9.92 hour rotation period of Jupiter, as the field sweeps over them.

On the other hand, opposite Earth's current field, Jupiter's mangetic north pole is in the northern hemisphere. (On Earth, just think about that fact that a compass's north is attracted to Earth's 'north', making the latter secretly south.)

If you want some wild magnetic axis action, with a really massive tilt relative to the spin axis, check out Uranus and Neptune. Both have wicked tilts, around 60 degrees.

Thin Oxygen Atmosphere

[Bonker]

Emissions of light (at wavelengths of 595 to 645 nanometers) likely arise from a tenuous atmosphere of oxygen. These glows would appear red to the eye and are consequently colored red in the movie.

Io is also brutally hot, has lots of tectonic activity, and hot and cold running Sulphur Volcanoes.

Still, there is this little tidbit from Solarviews [solarviews.com]:

The temperature on Io's surface is about -143 C (-230 F); however, a large hot spot associated with a volcanic feature measured about 17 C (60 F). Scientists believe the hot spot may be a lava lake, although the temperature indicates the surface is not molten. This feature is reminiscent of lava lakes on Earth.

My imagination can't help but be stirred by the idea of an open air Ionian resort hotel with swimming pools heated by molten Sulphur and with a dramatic view of Jupiter in the background.

*sigh*... The problems with this is that IO apparently has very little radiation shielding in comparison to earth. Sure you could land there... maybe even walk around, but if you took off your radiation shielding or went outside the sheilded dome, you'd get a fatal tan almost instantly, I think.

Also, while there is an atmospehre, IO is not much more massive than the Earth's moon. Even if it does have oxygen, you'd have to compress and mix it with something other than vaporized sulphur before humans could breath it.

Still, what an idea...

Re:Thin Oxygen Atmosphere

[CheshireCatCO]

has lots of tectonic activity

Tectonics? Not really. If there is, we can't really see evidence of it, with all the volcanoes. Perhaps you mean volcanic activity, which is a (somewhat) different beast?

Sulphur Volcanoes.

The more recent evidence (past couple of years) points to silicate volcanism, rather than sulphuric. This is because we have higher resolution IR images of the surface, and the lava is really hot (1200 K, I think). This points to silicates rather than sulphur. Also, Io's topography has long been known to be too varied to be supported by sulphur.

you'd get a fatal tan

Nope. Sorry, but I get frustated when people seem to perpetually confuse particle radiation and electromagnetic radiation. The latter can give tans. The former will simply kill you, in high enough dosage. It's particles that are trapped in the Jovian magnetosphere and which pepper the surface of Io.

Solar Max

[Nyphur]

It would be very interesting to see how Jupiter's magnetic field varies during solar max. Though the probe would need a better form of protection against the more intense solar winds in order to take good pictures. We don't have magnetographs of earth during solar max yet, do we?

Re:Solar Max

[CheshireCatCO]

Oh, the solar wind isn't (much of?) an issue. Probes have survived solar maximum near Earth (SOHO, for instance), and the wind becomes less intense like 1/r2 as you move away from the Sun.

Re:Solar Max

[Nyphur]

True, the levels are low but at solar max you'd get more electromagnetic interference. Remember, you still have to send the images back to earth in some form of EM stream so I hope the ammount is neglegable (usually is) but if it turns out to be too high, the pictures may be distorted more than usual. Do you know how NASA seals with signal degredation? Perhaps they use a biyt parity system, which would take a long time but NASA have got the time to spare for such invaluable information.

Re:Solar Max

[CheshireCatCO]

Signal degredation is not really an issue. The solar wind isn't going to affect radio waves that much. Witness Galileo's abilty to send back signals during solar maximum and continuing contact with Pioneer 10 and Voaygers I and II.

Oohhh...Look at the Pretty Pictures

[Special Ed]

Alright, this isn't geeky science stuff (and I freely admit that I'm a geeky-science type!)and a little off track but it's good to see someone else uses cool space photos for their Windows background.

I've downloaded over a 100 images from AstroPix. [nasa.gov] I wrote a nice little batch file (sorry, not C++ or whatever. Just good old Apple BASIC from elementary school) that ensures I have a new screen background everytime I log onto my computer. If anyone is interested, just email me.