The X-ray rings are only the start of strange things happening at V404 Cygni.
This black hole's X-ray images make it looks like the object is blowing smoke rings into the cosmos. What you see here is an image of V404 Cygni, a black hole about 7,800 light-years away from Earth.
As V404 nabs material from a nearby star, it throws the dust and gas into a disk that glows in X-rays — hence the rings. Astronomers have suggested that the spin of the black hole is misaligned with the plane of the orbiting star, causing the black hole's gravitational influence to warp the nearby space-time zone (this effect is called "frame-dragging.")
Here you can see a 2015 outburst that caught the eye of astronomers. The newly released composite image not only shows off the spectacular rings, but also gives astronomers more information about dust clouds nearby the black hole.
"The diameter of the rings in X-rays reveals the distances to the intervening dust clouds [from where] the light ricocheted off," stated officials from NASA's Chandra X-ray Observatory, a telescope that participated in the study.
"If the cloud is closer to Earth, the ring appears to be larger, and vice versa. The light echoes appear as narrow rings rather than wide rings or haloes because the X-ray burst lasted only a relatively short period of time."
The team, led by Sebastian Heinz of the University of Wisconsin in Madison, took a look at several telescopes' data from the 2015 outburst to probe the dust clouds, finding that most of the grains are likely graphite and silica. More importantly, the observations found that the dust cloud is not the same density in all directions, contradicting the theory suggested in previous studies.
While V404 is the focus of two Heinz-led studies in The Astrophysical Journal of 2015 and 2016 (available here and here), the larger implication is that the observations paint a picture of the landscape in between V404 and Earth, Chandra officials stated. For example, newer studies have been comparing V404 to other black holes to learn more about its outflows — which may tell us more about the evolution of these always fascinating objects.
“There have been multiple papers published every year reporting studies of the V404 Cygni outburst in 2015 that caused these rings,” Chandra’s officials noted. “Previous outbursts were recorded in 1938, 1956 and 1989, so astronomers may still have many years to continue analyzing the 2015 one.”
Other participating observatories in the study of V404 include the Neil Gehrels Swift Observatory (which often looks for gamma-ray bursts in objects) and the Pan-STARRS telescope in Hawaii (which is valuable to astronomers due to its ability to look at large swaths of sky from the ground, instead of tiny areas.)
