NASA Records Supernova Debris Moving At 20 Million Miles Per Hour

In 1604, early astronomers, including Johannes Kepler, observed a supernova explosion named for Kepler. The star that exploded was about 20,000 light-years away from The Earth in the Milky Way galaxy. The star in question was a Type Ia supernova resulting from the explosion of a small and dense white dwarf star.

Astronomers have used the Chandra X-ray Observatory to record material moving away from the supernova at speeds higher than 20 million miles per hour. NASA points out that is about 25,000 times faster than the speed of sound on Earth. The study tracked 15 small "knots" of debris in the Kepler supernova remnant that are glowing with X-rays. The fastest knot of debris was measured at 23 million miles per hour, the highest speed recorded for a supernova remnant.

The average speed of the knots is about 10 million miles per hour, with the blast wave expanding at about 15 million miles per hour. Scientists used a new sequence of images in their latest speed estimates that look at x-rays in red, green, and blue revealing low, medium, and high energy x-rays, respectively.

One interesting finding in the study is that some knots of debris from the Kepler supernova have hardly slowed due to collisions with material surrounding the remnant in the 400 years since the explosion was first seen. There are 15 knots of material moving away from the explosion site with eight moving away from Earth and two moving towards it. The other knots require more study.

As for why the material is moving so fast, scientists aren't sure. They believe that the supernova could have originated from an unusually bright Type Ia, which could account for some of the debris tunneling through regions of low density and not decelerating. The researchers believe that there could have been a merger between two white dwarfs to create the explosion.