One of the most dramatic events in the universe is the death of massive stars. When stars much more massive than our Sun run out of fuel and explode in enormous supernovae, these events not only release enormous bursts of energy but also change the environment around them. When the shock wave from the explosion travels millions of miles into space and hits clouds, dust and gas, it can create complex and beautiful structures called supernova remnants.
One of the most famous remains is the Cygnus Loop, a bubble-shaped object about 120 light years across. Hubble imaged the remains in 2020, and now scientists are using this Hubble data to study how the remains have changed over time.
“Hubble is the only way we can observe what’s happening at the edge of the bubble so clearly,” Ravi Sankrit of the Space Telescope Science Institute, lead author of the new research, said in a statement. statement. “Hubble images are spectacular if you look at them in detail. This tells us about the density differences caused by supernova shocks as they propagate through space, and the turbulence in the region behind those shocks.”
The shock moved at incredible speeds of more than half a million miles per hour, which researchers were able to calculate by comparing Hubble observations from 2020 and 2001 to see the shock’s expansion over time. The results can be seen in a time lapse video on the Hubble website. One surprising finding is that the shock has not abated at all at this time.
The images look like filaments because we see them from the side, like a crumpled sheet, the researchers explained. “You see ripples on the sheet that peek out from the edges, so it looks like twisted bands of light,” says William Blair of Johns Hopkins University. “These waves occur when shock waves encounter more or less dense material in the interstellar medium.”
Its shape is created by shocks moving through the interstellar medium, which is the thin region of dust and gas between star systems. “When we pointed Hubble at the Cygnus Loop, we knew that this was the leading edge of the shock front, which is what we wanted to study. When we got the initial images and saw these incredible, subtle bands of light, it was a bonus. “We didn’t know it would complete a structure like that,” Blair said.
This research was published in Astrophysical Journal.