A supernova is an explosion of intense brightness. It is the largest explosion that occurs in space. A supernova occurs when the core of a star, for some reason, collapses. This collapse can occur in two different ways, resulting in a supernova.

The first type of supernova occurs in binary star systems. Binary stars are two stars that orbit at the same point. When one of the stars is a white dwarf, composed of carbon-oxygen, it steals matter from its companion star. The white dwarf probably accumulates too much matter. Having too much matter causes the star to explode, resulting in a supernova.

The second type of supernova happens at the end of the life of a single star. As the star's nuclear fuel runs out, some of its mass flows into the core. Consequently, the core gets heavier and, at some point, the weight is so great that the star cannot support its own gravitational pull. The core collapses, resulting in the giant explosion of asupernova.

Animated simulation of supernova 1987A. Image: NASA

During the supernova explosion, for a short period, there is an effect similar to the emergence of a new star, however, this brightness gradually disappears over a period of time that can vary between weeks or months.

In some cases, the supernova's brightness is so intense that it is about 1 billion times brighter than its original light, making the star as bright as a galaxy, but as we explained in the previous paragraph, its temperature and brightness slowly decrease.

Why scientists study supernovae

A supernova burns for a relatively short period of time, but it has a lot to tell scientists about the universe, because the occurrence of a supernova demonstrates that we live in an expanding and constantly changing universe.

Researchers have found, at the bottom of the Pacific Ocean, remnants of a possible supernova that occurred near Earth. Image: WikiImages/Pixabay

In addition, scholars have also determined that supernovae play a key role in the distribution of elements throughout the universe. After all, when a star explodes, it spews elements and debris into space. These elements travel throughout the universe and can form new stars and even planets.

How supernovae are studied

The first studies on supernovae were carried out in the 1930s by Walter Baade and Fritz Zwicky at the Mount Wilson Observatory in California, USA. These astronomers were even the first to use the term "supernova".

Because supernovae are somewhat rare events within a galaxy, and occur about three times per century in the Milky Way, obtaining a good sample of supernovae to study requires regular monitoring.

Supernovae in other galaxies cannot be predicted accurately, which means that when they are discovered, they are already in progress. Most scientific interests in supernovae, as a standard for measuring distance, for example, require an observation of their peak luminosity. Therefore, it is important to discover them well before they reach their peak.

Currently, NASA scientists use different types of telescopes to search for and study supernovae. Some telescopes are used to observe the visible light from the explosion; others record X-ray and gamma-ray data that is also produced, while NASA's Hubble Space Telescope and the Chandra X-ray Observatory capture images of supernovae.

• Long astronomical hunt for extragalactic "ghost particle" source yields results
• How does a black hole form?
• Scientists announce the discovery of the toughest material in the universe
• Hubble records startling image of a star turning into a black hole
• Stellar explosions led the first humans to walk upright