When stars in Andromeda galaxy explode they are 10,000 times brighter than the Sun

During these explosions, new chemical elements are made, and some of the star's material is thrown out into space.

In Short

• Astronomers looked at these suns located in the Andromeda galaxy
• Scientists have examined explosion at visible wavelengths
• Andromeda galaxy was chosen for observation as it is visible clearly

A team of astronomer from the Indian Institute of Astrophysics (IIA) have discovered that some exploding stars, called novae, shine 10,000 times brighter than the Sun.

Novae are big, bright explosions that happen on stars called white dwarfs. These white dwarfs are pulling in material from nearby stars. When enough material builds up on their surface, it causes a huge explosion, making the star system much brighter for a while.

During these explosions, new chemical elements are made, and some of the star's material is thrown out into space. By studying novae, scientists can learn about how galaxies change over time and how space between stars gets filled with different materials.

SUNS GO BOOM

Astronomers looked at these suns located in the Andromeda Galaxy, which go through quiet phases both before and after their explosions, during which they emit ultraviolet (UV) light.

During these dormant phases, they emit ultraviolet (UV) light, which had not been thoroughly studied in previous research. Traditionally, scientists have examined novae at visible wavelengths, overlooking the potential importance of UV emissions.

Andromeda galaxy was chosen for observation as it is visible clearly for more than half of each year, it's relatively close to us and can be seen most face-on. It also has lots of novae happening frequently.

The astronomers studied these stars using UV data collected by AstroSat, India’s space observatory. While past studies focused on visible light from novae, this research looked at UV light, offering new insights into how these stars behave.

42 EXPLOSIONS OBSERVED

The team analyzed 42 novae, most of which are found near the center of the Andromeda Galaxy, a region full of bright galactic light that usually hides these stars.

Using special techniques to filter out the galactic light, they found 23 novae in their quiet phase, 21 just after their explosions, and 4 in both phases.

Most of these novae are white dwarf stars, which gather material from nearby companion stars. The UV light mostly comes from an "accretion disk," a spinning disk of material falling onto the white dwarf during its quiet phase.

This research is important because novae spread heavy elements, which are needed for life, into space where new stars are born.

The findings, published in The Astrophysical Journal, could help us better understand how stars evolve and influence galaxies.