While astronomers have seen debris from the score of Exploding stars in the Milky Way and nearby galaxies, it is often difficult to determine a star’s death date. By studying the spectacular Remnants of a Supernova in a nearby galaxy using NASA’s telescope, a team of astronomers found enough clues to help turn the clocks back.
Image credit: NASA
The supernova remnant, SNR 0519-69.0 (abbreviated as SNR 0519), is debris from an explosion of a white dwarf. After reaching a critical mass, either by pulling matter from a companion star or merging with another white dwarf, the star undergoes a thermonuclear explosion and is destroyed. Scientists use this type of supernova, called Type Iadedicated to a wide range of scientific research, from studying thermonuclear explosions to measuring distances to galaxies in billions of light-years.
SNR 0519 is located in the Large Magellanic Cloud, a small galaxy 160,000 light-years from Earth. This composite image shows X-ray data are from NASA’s Chandra X-ray Observatory and optical data from NASA’s Hubble Space Telescope. X-rays from SNR 0519 with low, medium, and high energies are shown in green, blue, and violet, respectively, with some of these colors overlapping to appear white. Optical data shows that the circumference of the ruins are red and the stars around the ruins are white.
Astronomers combined data from Chandra and Hubble with data from retired NASA Spitzer . space telescope to determine how long ago the star in SNR 0519 exploded and learn about the supernova’s environment. This data gives scientists the opportunity to “rewind” the movie of the brilliant evolution that has taken place since then and figure out when it began.
The researchers compared Hubble images from 2010, 2011 and 2020 to measure the speed of matter in the blast wave from the explosion, which ranged from about 3.8 million to 5.5 million miles (9 million) km) per hour. If the speeds were above those estimated speeds, astronomers determined that the light from the explosion would have reached Earth about 670 years ago, or during the Hundred Years’ War between England and France and the peak. high of the Ming Dynasty in China. .
However, it is likely that the material has slowed down since the initial explosion, and that the explosion occurred more recently than 670 years ago. Chandra and Spitzer’s data provide clues that this is the case. Astronomers found the brightest region in the remnant’s X-rays to be the site of the slowest-moving matter, and none of the X-ray emission associated with the fastest-moving matter.
These results imply that some of the explosive waves crashed into the dense gas surrounding the ruins, causing it to slow down as it moved. Astronomers can use additional observations with Hubble to more accurately determine when the star’s demise should actually be established.
Source: National Aeronautics and Space Administration
