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New Class of "Hypervelocity Stars" Discovered Escaping the Galaxy
Science_afficionado writes "Astronomers have discovered a surprising new class of 'hypervelocity stars' that are moving at more than a million miles per hour, fast enough to escape the gravitational grasp of the Milky Way galaxy. The 20 hyper stars are about the same size as the sun and, other than their extreme speed, have the same composition as the stars in the galactic disk. The big surprise is that they don't seem to come from the galaxy's center. The generally accepted mechanism for producing hypervelocity stars relies on the extreme gravitational field of the supermassive black hole that resides in the galaxy's core."
A million miles per hour is not all that much.
All the galaxies in our neighborhood are also rushing at a speed of nearly 1,000 kilometers per second (2,236.936 miles per hour) towards a structure called the Great Attractor, a region of space roughly 150 million light-years away.
In addition, our solar system--Earth and all--whirls around the center of our galaxy at some 220 kilometers per second, or 490,000 miles per hour.
The earth is moving toward the Constellation Leo at the dizzying speed of 390 kilometers per second. (872,405 miles per hour).
Lots stuff going places fast.
Now if you find an inhabitable planet orbiting one of these stars let me know. That would be the mothership of all motherships.
Sig Battery depleted. Reverting to safe mode.
If one considers the rest frame of the microwave background as the rest frame of the universe, then yes, one can answer these questions.
http://en.wikipedia.org/wiki/Cosmic_microwave_background
Due to the Doppler effect, you see the frequency shift if you move relative to the microwave background, which would otherwise be (almost) the same blackbody radiation of temperature 2.725 K from all direction.