Why It Matters That India and the US Teamed up to Measure a Black Hole’s Spin

The black hole’s spin rate also turned out to be close to the theoretical maximum. Beyond that limit, black holes lose their event horizons.

Image for post
Image for post
An artist’s illustration of a black surrounded by an accretion disk, as in the discovery of 4U 1630–47. Credit: NASA/JPL-Caltech
This article was originally published for The Wire. This is a mirror of the same.
Image for post
Image for post
An artist’s illustration of a black hole accreting matter from a companion star. Credits: ESO/L. Calçada
Image for post
Image for post
The X-ray detector LAXPC, onboard AstroSat. Credit: ISRO
Image for post
Image for post
X-ray spectrum from the accretion disk of the black hole 4U 1630–47, as seen by AstroSat’s SXT and LAXPC as well as Chandra’s HEGTS. Credit: Mayukh Pahar, A R Rao, et al., October 2018.
Image for post
Image for post
Black hole spin measured using AstroSat and Chandra observations. Credit: Mayukh Pahar, A R Rao, et al., October 2018.

Written by

Science writer passionate about space exploration and the Moon. Words at The Planetary Society, The Wire Science and more. All articles at www.jatan.space

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store