The race to map the space around the supermassive black hole at the center of our galaxy

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The uncertainty of science: Using a new generation of telescopes, in space and on the ground, astronomers hope to better confine Einstein’s General Theory of Relativity by studying the distortion in light and energy produced by the powerful gravitational field surrounding Sagittarius A* (pronounced A-star), the 4 million solar mass black hole at the center of the Milky Way.

This is an excellent article explaining both the limits of our ability to study black holes as well as what we do know about Sagittarius A*.

Correction: Thanks to commenter Mike Nelson for noticing that I had mistakenly written “billion” instead of “million” for the mass of Sagittarius A* above.



  • Max

    Fascinating stuff. A star with so much gravity that light cannot escape. (pun intended)
    Any gravity field that can warp space also warps time. Inside the event horizon, time comes nearly to a stop. Any photons that could leave would be so slow, after passing through the time distortion, that it would no longer appear as light. (400 nm to 700 nm) What few photons per second escapes the event horizon would appear In the infrared, microwave, shortwave or lower wavelength due to the distortion.
    I would think that any light passing through the distortion field bending around A* would also be changed by the time or gravitational effect and appear in a lower wavelength.
    I always thought this was the case for super massive red stars. These could be Proto black holes who’s gravity field is shifting the wavelength of light into the red as it enters our time reference.
    The same can be true for magneto stars. If the stars magnetic field is so strong that light pressure has to build up before its release, this will force light into the bright blue, ultraviolet, and x-ray part of the spectrum. (just as it does on our Sun, the brightest portion of the sun is the dark spots because they emit light at a higher wavelength that we cannot see giving them the appearance of darkness when the opposite is true)
    sunspots are also cooler than their surroundings. Is the strong magnetic field forcing electrical activity away from the area allowing cooling? The electrical activity that cannot escape the magnetic field must build up enough pressure to overcome the magnetic resistance and explode outward in a burst of highly charged ions… That makes my AM radio staticky! Not to mention all those spectacular flares.

  • Mike Nelson

    Just fyi Sag A* is estimated to be 4 Million solar masses, not 4 Billion.

  • Whoops! Thanks for catching the typo. Didn’t even see it. Now fixed.

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