Ok, here is how it works: we look at a galaxy though a big telescope.We measure the density of stars in different parts of the galaxy in question. Then we measure the doppler shift, and corresponding rotational speed for different areas of the galaxy.
Now we notice a real problem; the galaxy rotates too fast. In fact our theories predict that in order to rotate as fast as it does, our galazy needs to be twice as large, and have about ten times as much mass as we have just measured. Try as we may, we just cant account for the "missing mass."
Ok, no sweat, Its probably just an anomaly. So we measure the galaxy again with different equipment, we collect twice as much data. We measure lots of other galaxies. It's the same story everywhere, galaxies rotating way to fast, and we can't find any of the "missing mass".
Ok, so either our measurements are wrong, or our theory is wrong. But our theory can't be wrong! So all that extra matter must be there, we just can't find it!...
2007-03-21
05:34:00
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13 answers
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asked by
WOMBAT, Manliness Expert
7