As part of Citizen Science Month 2023, we’re sharing excerpts from ‘Into the Zooniverse’, a series of books celebrating the projects and people of the Zooniverse.

You can find and download all editions of ‘Into the Zooniverse’ here.

SuperWASP: Black Hole Hunters

BLACK HOLES ARE MADE when massive stars die. The majority of stars live with a companion in what’s called a binary system. After a massive star’s death and supernova, the resulting black hole and its companion star orbit each other around their common center of mass. Whenever a massive object passes in front of a normal star we observe ‘micro-lensing,’ which looks like the light is bending due to the curving of space-time. When this happens we are able to detect a characteristic periodic increase in the light. If we are able to estimate the mass and radius of the normal star, we can also do the same for the black hole. We have just found those hidden black holes!  

Through the Black Hole Hunters project led by astronomers at the Open University and the University of Southampton, Zooniverse volunteers search for tell-tale signals that may reveal the black holes in our galaxy. These signals are extremely rare. Only a handful of black holes will be orbiting in a plane that passes directly in front of their companion star. Humans are especially good at seeing patterns in data that are similar to examples they are given. That is why there are simulated lensing events mixed into the subjects. This gives volunteers an example of what shapes to look for in the rare event a real lensing event is captured. 

Image credit: SuperWASP Team, Black Hole Hunters Project

Summary by: Sean Miller

Check out this project: here

View the full ‘Into the Zooniverse’ book: here