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Star Flung From Milky Way at High Speed

Posted by Zonk on from the knocked-one-out-of-the-park dept.

fenimor writes "Using the MMT Observatory in Tucson, astronomers have discovered a star three times bigger than the sun, leaving our galaxy at a speed of over 1.5 million miles per hour (670 kilometers per second). The first-of-its-kind finding not only confirms an earlier theory about the existence of such speeding stars, but also reinforces the notion that the Milky Way spins around a black hole."

3 of 512 comments (clear)

  1. To put that in perspective... by GillBates0 · · Score: 5, Informative
    That's 0.002 times the speed of light or only about 1/500th the speed of light.

    Plugging 670*10^3m/s into Lorent'z equation:

    t = t'/(sqrt(1-(v^2/c2))
    where v=6.7*10^5m/s
    and c = 2.99*10^8,

    I got a time dilation of factor of 1.00000249. That is, time in the moving system (the star) will be observed by a stationary observer to be running slower by a factor of 1.00000249.

    Not as impressive as I hoped it would be when I started the calculations.

    --
    An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
  2. Supermassive black holes by Spy+der+Mann · · Score: 5, Informative

    Recently I saw on Discovery that many galaxies (if not all) were orbiting around supermassive black holes. And that the orbiting speed of the stars is proportional to the black holes' mass. This is known as the "M-sigma" relation.

    This meant that the supermassive black holes actually contributed to the process of galaxy formation.

    The theory is more or less the following:

    In the center of a galaxy-sized gas cloud, a star collapsed, forming a black hole. The black hole began eating the gas around it, forming a quasar (quasars are the matter just about to be swallowed by a black hole, disintegrating and generating enormous amounts of energy).

    The quasar, due to its high temperature and rotational speed, heated the surrounding gas cloud, activating a chain reaction that gave birth to all the stars in the new-forming galaxy.

    Eventually, the quasar pushed away the stars, so the black hole could only be fed by the quasar itself. After that, the black hole enters a dormant phase (it has nothing else to eat), and the galaxy is already formed (of course, I'm talking about a process that takes billions of years).

  3. Explanation by af_robot · · Score: 5, Informative

    For those, who didnit get it.
    Puppeteers are alien race from novel "Ringworld" by Larry Nivel. They were moving their home star system to a new galaxy to escape from the Core explosion.