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Mission Complete! WMAP In 'Graveyard Orbit'
astroengine writes "The Wilkinson Microwave Anisotropy Probe (WMAP) has, quite literally, changed our view of the Universe. And after nine years of mapping the slight temperature variations in the cosmic microwave background (CMB) radiation, its job is done and NASA has commanded the probe to fire itself into a 'graveyard orbit' around the sun. WMAP measured the most precise age of the universe (13.75 billion years), discovered more evidence supporting dark energy and dark matter theories, and found one or two mysteries along the way."
So Dark Matter was a theory invented to explain why stars orbit a galaxy's core like they were on spokes around the hub of a wheel ...instead of how we observe the motion of object orbiting our sun. So if Dark Matter exerts such a huge force to keep huge objects (stars) moving in such a manner, how come that same force doesn't affect the objects going around the star? Or, in other words, if it's powerful enough to keep the outer-most stars in a galaxy moving in the same period as inner stars, how come we can't detect it here? Or have we detected such tidal forces already?
While there's a lot of dark matter in a galaxy compared to "normal" matter, it's typically spread out over a much larger volume than the viewable parts of a galaxy. Thus, it is actually quite diffuse and has very little effect within something on the scale of a solar system (to the point of being unmeasurable with current technology).
The dark matter halo around our galaxy is theorized roughly as a large sphere, not just extra mass along the flattened wheel of the spiral. Look at the graphic here: http://startswithabang.com/?p=656
That's a lot of extra room. So much so that even when those researchers calculated that our solar system should have 300 times the dark matter density compared to the galactic dark matter halo, this only ends up being a very tiny fraction of the earth's mass in dark matter bound to our solar system. See: http://www.universetoday.com/15266/dark-matter-is-denser-in-the-solar-system/
So basically, it's going to be rather difficult to detect dark matter nearby.
The prior orbit was at the L2 point http://en.wikipedia.org/wiki/Lagrangian_point#L2 one of the very few stable points in the solar system. Leaving WMAP there would be a bad idea because it makes a very nice spot become more hazardous. We're already having serious trouble with spacejunk in Earth orbit. There's no good reason to star trashing up the rest of the system also.
I concur, and a favorite comic springs to mind:
Science: It works, bitches
From the wikipedia page about the CMB:
Two of the greatest successes of the big bang theory are its prediction of its almost perfect black body spectrum and its detailed prediction of the anisotropies in the cosmic microwave background.
When basically the whole observable universe matches your theory, it's generally considered pretty strong evidence that you're going in the right direction.
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.