Nautilus - How to recognize a black hole
The supermassive black hole at the center of this galaxy, around 11 million light years away toward the constellation Centaurus, is currently classified as a quasar. It is roughly 55 million times more massive than our Sun. Its collimated jets, in blue, surpass the diameter of the entire galaxy, extending up to 13,000 light years. The Milky Way, by comparison, is roughly ten times this length. Credit: NASA/CXC/CfA/R.Kraft et al.; MPIfR/ESO/APEX/A.Weiss et al.; ESO/WFI.
I wrote a blog for Nautilus Magazine's Identity issue on how the classification system for galaxies with supermassive black holes leaves a lot to be desired.
Astronomers can sometimes be literal to a fault. We like to call things as we see them. For example, if it’s red and it’s huge: “Red Giant.” White and small: “White Dwarf.” Massive explosion: “Big Bang.” Dark and sucks everything in: “Black Hole.” Most of the time, classifying objects this way works fine—either it’s new, or it’s something we already know of. But sometimes, as with Pluto, we make new observations that force us to question the name, reassess the object, and identify it differently. You might think this never happens with something as clearly defined as a black hole, but you’d be wrong.
Read the full article here.
