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    Saturday in Space: Quasars
    By Bente Lilja Bye | January 19th 2013 08:05 PM | 2 comments | Print | E-mail | Track Comments
    About Bente Lilja

    Earth science expert and astrophysicist writes about Earth observation, geodesy, climate change, geohazards, water cycle and other science related...

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    No, it is NOT a star! Several orders of magnitudes far from being a star actually. I am talking about quasars (quasi-stellar radio source) - often being described as distant stars. Oh, astronomers pain.

    Quasars are absolutely fascinating. Little understood yet being used in our daily lives. Yes, you read me correctly. Since quasars are so far away and only move ever so slightly on the sky, we can use them as fixing points for our reference frame. The reference frame is the coordinate system we define all positions in and is one of the geodetic products. You might have heard about VLBI - Very Long Baseline Interferometry radio antennas in astronomy. They are actually being use for more earthly matters as well. The IVS provides us with observations of a selected group of quasars and combined with GPS and other space-based and in-situ instruments we get the high accuracy positioning products we all enjoy on a daily basis.

    I also find this heavenly objects to be quite pretty. Enjoy!

    Quasar
    The jet (blueish color) was produced by a quasar named GB 1428+4217, or GB 1428 for short, and is located 12.4 billion light years from Earth. Credits: X-ray: NASA/CXC/NRC/C.Cheung et al; Optical: NASA/STScI; Radio: NSF/NRAO/VLA

    Learn more about Quasar on BBC or continue reading on NASA

    Comments

    MikeCrow
    They now think Quasars are feeding super massive black holes that exist in the hearts of all galaxies (~5% of the galaxies mass). Since some have quite large redshifts, and are still quite bright their output is of a scale that puts all other (except the Big Bang) energy sources to shame.
    It's also believed that the very highest energy cosmic rays (a single proton that pack the punch of a major league fastball) that hit Earth are from feeding SMBH's.
    Never is a long time.
    Stellare
    Yes, I think I read that somewhere too. :-) They are quite fascinating these quasars.
    Bente Lilja Bye is the author of Lilja - A bouquet of stories about the Earth