Exploding stars are a key point of focus for scientists who hope to understand the lifecycle of stellar bodies and how they interact with their surroundings.
Supernovae are undoubtably one of the cosmos’ greatest actors. They put on spectacular shows unrivalled by anything we could fathom; some supernova being 2nd only to the big bang in the amount of energy produced by one single event.
But now, researchers at the NASA Chandra X-ray Observatory have been studying one particular explosion that they believe may provide clues to the dynamics of other, much larger eruptions. These explosions are called “classical nova”, and they’re the smaller cousins of Supernovae.
In 1901 a star suddenly appeared in the night sky as one of the brightest ever seen, for just a few days. Before it faded away, astronomers had deduced that this was infact the first ever witnessed classical nova – and the object became a rapid sensation in the astronomical world. This star was known as GK Persei.
Today, we are still studying GK Persei, and the team at Chandra has found some interesting data that may help to understand the evolution of stars. The nova’s debris is expanding at a speed of 700,000 miles per hour which translates to the blast wave moving about 90 billion miles.
GK Persei is a white dwarf star that pulled in material from orbiting companion stars. When enough material accumulated on the surface of the star (in the form of hydrogen gas) nuclear fusion takes place and culminates into a hydrogen-bomb like explosion on a stellar scale. The outer layers of GK Persei were blown away, which produced the nova outburst visible here on Earth.
Building The Case
Observing GK Persei from 2000 to 2013 gave astronomers at Chandra an opportunity to build a 13 year baseline on the event and collect a significant amount of data to notice important differences in x-ray emissions and life cycles. What was so important about this research was the understanding of the nova’s dynamic; while a nova is a much smaller version of a supernova, it is still expected to be so bright that it will outshine all stars in the galaxy it is found in. Additionally, novas are very important for cosmic evolution as they blast iron, calcium, and oxygen into space – which helps with the formation of new stars and planets.
One discovery in the search shows that nova remnants can provide extremely important clues to the environment of the solar system at the time of the explosion. By measuring the changes in density before and after the explosion, scientists can determine how the blast wave passes through the cosmos, which ultimately paints a picture of the density of its current and previous region of space.