Voyager 2 Shows Solar System Is "Dented"

Selikoff writes "NASA's Voyager 2 spacecraft has found that our solar system is not round but is 'dented' by the local interstellar magnetic field, space experts said on Monday. The data were gathered by the craft on its 30-year journey when it crossed into a region called the 'termination shock.' The data showed that the southern hemisphere of the solar system's heliosphere is being pushed in. Voyager 2 is the second spacecraft to enter this region of the solar system, behind Voyager 1, which reached the northern region of the heliosheath in December 2004."

Shape?

[TitusC3v5]

Could somebody explain how exactly the solar system has an innate 'shape'? I would think that that would be human-defined, not an actual, measureable feature.

I, for one...

[sammydee]

Actually think it's awesome that even twenty YEARS after it's launch, voyager 2 [wikipedia.org] is STILL doing useful science. Another thing that astounds me is how the engineers managed to ensure that even after all these years in the hostile environment of space, this machine is still perfectly functional.

Re:Shape?

[Kranfer]

Its not the solar system that is dented but its far reaches where the solar wind suddenly slows down that is 'dented'. Figure a magnetic field or a sphere that is effected by its environment and causes it to lose its shape... The area where the solar wind slows down changes in shape due to interstellar influences... gasses, magnetic fields, etc... From a few articles I read on this the other day Voyager 2 passed through the terminal shock numerous times so far and will again in 2008 because it is constantly changing shape. Although I may be wrong, and I have been up all night sick and decided to go into work at 4 am... I dunno what the hell is wrong with me lol.

Re:Shape?

[MichaelSmith]

Could somebody explain how exactly the solar system has an innate 'shape'? I would think that that would be human-defined, not an actual, measureable feature.

Well the Sun has an innate shape. It is mostly a sphere, flattened a little bit by rotation. Other factors such as magnetic fields will play a part.

The solar wind is really the outer part of the sun, so in one sense we are embedded in the sun, and it flows around our planet. It has long been expected that the solar wind would meet the interstellar medium at some sort of bow shock on the upstream side with a tail of sorts on the downstream side.

This article suggests that magnetic fields which exist between stars also affect the shape of the boundary between the solar wind and whatever is outside it. Instruments on the Voyager spacecraft tell us which medium it is in at any point in time.

Its not really hostile

[MichaelSmith]

• Temperatures are extremely stable, so there is no expansion or contraction
• Your electronics can't get rained on or filled with dust
• There are no rats to eat your wires (yet)
• There are no engineers around to fiddle with it and improve it (yes I know this does happen to software)
• Cold is generally good for equipment, but not too much of course.
• Your chance of being hit by a meteor is probably less than on Earth
• etc

If I ever do the transhuman thing and get turned into software, The Oort cloud is where I would want to be for serious durability.

Re:I don't get it

[sqldr]

As an analogy, it's like smoking. You're breathing particles at up to 6000 degrees C, but it doesn't do (much) damage.

Re:Shape?

[Gabrill]

Ok how long apart are these 2 (count them 2) points of reference? V2 also crossed the boundary what, 5 times? It seams to me that this could be stronger evidence that the whole thing fluctuates in size, rather than having a hard, irregular boundary.

Re:How does it stand the thermal shock?

[fbjon]

How dense is the matter and how do you measure this kind of energy?

Very sparse. With a thermometer.

Re:human defined?

[orclevegam]

Pi? I've certainly never seen a complete definition of it, only approximations.

Re:Its not really hostile

[Anonymous Coward]

RCA did a damn fine job with its rad-hardened version of the CDP1802. That and the fact that, at the time, it was about the only low power CMOS microprocessor out there made it a popular choice for space applications. I've read that the engineers had some qualms about the chip's rather unconventional, simple instruction set, but it seems they made the most of it despite their misgivings.

More about the 1802 here [wikipedia.org] for your daily dose of geek history.