GoKawiilThe James Webb Space Telescope (JWST) was designed to give us the ability to look at one of the earliest periods in the evolution of the Universe, a time when some of the earliest stars were putting out enough light to ionize the hydrogen that accounted for almost all of the normal matter present at the time. There were lots of ideas about what we might see, but the Universe is full of surprises.
One of the first surprises was the existence of what picked up the moniker “little red dots,” which are exactly what their name suggests. After some initial arguments, it became clear that these were early versions of the supermassive black holes that presently sit at the center of almost every galaxy. Now, gravitational lensing has allowed astronomers to confirm that a little red dot is little more than a supermassive black hole without much in the way of a galaxy around it.
Making a little red dot bigger
The little red dot in question is called Abell 2744−QSO1, and gravitational lensing has both magnified it and caused it to appear three times in the vicinity of the galaxy cluster that did the lensing. Based on details in its spectrum, we’re looking at the object as it appeared just 700 million years after the Big Bang.
We’ve already known about QSO1 for a couple of years, and it has been the subject of intense study. One paper noted that the three lensed images of the object differ in some of their details. Since the light from each of those took different paths to Earth, and thus different amounts of time, this suggests there have been variations in QSO1’s emissions—consistent with a black hole feeding on different amounts of material over time. And, based on the luminosity of the object, people had estimated that the black hole itself was quite large for that early in the Universe’s history, at above 10 million times the mass of the Sun.