[To Scale] That Black Hole Picture

If you like scrolling you might enjoy the previous feature: solar-earth light ray diagram to scale.

In the spirit of that, and to answer some general complaints, “Why is the photo so blurry!?”… Here’s me attempting to put our first black hole portrait to human scales. Of course, this time it’s utterly impossible to put everything in one picture and expect anything to remain. Some compression is needed.

The estimate was made by treating the black hole as almost-Schwarzschild (duh) and that the inner rim of accretion disk is about three times that radius from the singularity. In reality, the black hole will be gently rotating and hence be described by the Kerr metric. This means our radius estimate may be smaller than reality.

To Scale …

Black hole image credit: https://eventhorizontelescope.org

†: Mass of M87 central black hole taken from Galaxy structure from multiple tracers: II. M87 from parsec to megaparsec scales, L. J. Oldham, M. W. Auger, ArXiv 1601.01323


Compiled in a morning bus.

Illustration version 3.