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First Images of Solar System's Invisible Frontier
FiReaNGeL writes an unexpected side-effect from NASA's STEREO spacecraft has allowed scientists to see a much more well-defined picture of the boundary of our solar system. "The twin STEREO spacecraft were launched in 2006 into Earth's orbit about the sun to obtain stereo pictures of the sun's surface and to measure magnetic fields and ion fluxes associated with solar explosions. Between June and October 2007, however, the suprathermal electron sensor in the IMPACT (In-situ Measurements of Particles and CME Transients) suite of instruments on board each STEREO spacecraft detected neutral atoms originating from the same spot in the sky: the shock front and the heliosheath beyond, where the sun plunges through the interstellar medium."
IMPACT (In-situ Measurements of Particles and CME Transient)
Dear God, an acronym inside another acronym! I think the space geeks have beat us computer geeks yet again.
Last chance for gas, 20,000,000,000 km. We have lotto tickets and cold beer!
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Would that be like recordings of silence or the smell of nothing?
I read Slashdot for the headlines, because the headlines, unlike the articles, are usually original and never duplicated
Wouldn't it be possible, using the sun as a center point, to measure the distance to the termnation shock vs the boundaries of the heliosphere to determine how fast and in what vector our solar system is moving through space relative to the center of our galaxy? Or has this already been done, 'cause I can't find the info.
Possibly, using this information, couldn't an orbital pattern of our solar system be extrapolated against the center of the galaxy as a reference point?
http://www.thebestpageintheuniverse.net/c.cgi?u=puns
int main() { while(1) fork(); }
Interstellar space isn't empty. You have nebula and lots of (hundreds of billions?) stars spewing particles just like the Sun does, etc. So there is something for the solar wind to run into.
Well, the gas into which the Sun is driving the termination shock could also have a mean motion relative to the Keplerian velocity at its distance from Galactic center so...no.
However, the Sun's motion relative to the Galactic center is reasonably well known. It is based on looking at the velocities of stars in the local neighborhood (which should be in the same general orbit around Galactic center), and assuming that the average of these would be zero IF the Sun had no velocity except that required for its orbit around Galactic center. The average isn't, so the Sun has an extra velocity component, which is just the negative of this average. (The technical terms used for these quantities are the "solar motion" and the "Local Standard of Rest".) It turns out to be around 16.5 km/sec diagonally inward and slightly upward from its rotation.
"I guess the moral of the story is, don't paint your airship with rocket fuel." -- Addison Bain
In our neighbourhood it's a a lot less dense than average.
Even taking the average of about 1 hydrogen atom per cc, if you had a tube 1 cm in diameter that stretched from here to Alpha Centauri, the total mass inside the tube would be 3e-12 grams.
So yes theres stuff out there, but it wouldn't ruffle your hair if you put the convertible top down on your spaceship.
Equine Mammals Are Considerably Smaller
TFA: The termination shock is the region of the heliosphere where the supersonic solar wind slows to subsonic speed as it merges with the interstellar medium.
Okay boys and girls. Quick, grab your calculator and calculate the speed of sound in space...
I was expecting a picture that didn't look like something I drew today at work using MS Excel and autoshapes.
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