Thai astronomers discover 13 galaxies with James Webb Space Telescope

A team from the National Astronomical Research Institute of Thailand (NARIT) used data from a set of images captured by the telescope to search for small-sized galaxies, NARIT announced in a Facebook post on Thursday.

The 13 newly observed galaxies originated at the dawn of the universe, around 13 billion years ago. NARIT said they are among the smallest galaxies ever found during the early epoch of the universe, with masses measuring 10 to 100 times less than our own Milky Way.

The discovery, which has been published in the Astrophysical Journal Letters, is helping astronomers unveil the secrets of early low-mass galaxies.

They emerged when the universe was around 550-700 million years old, during the period known as the Epoch of Reionization.

In this era, the hot gases left over from the Big Bang began to clump together as stars and galaxies. The James Webb Space Telescope is exploring the dawn of the universe by gathering data on the mass, age, shape, and even the metallicity of these galaxies.

However, observing low-mass galaxies poses challenges as they lie on the very edge of the imaging capabilities of even the James Webb telescope, which orbits the Sun about 1.5 million kilometres away from the Earth.

After calculating data from these newly discovered galaxies, the astronomers found that they are currently producing new stars at a rate of 1-10 per year. The age of the stars within these galaxies ranges from 30 to 200 million years, consistent with the theoretical predictions of astronomers.

Utilising the star ages, the research team was able to create a simple formula to estimate the rate of new star formation and the mass of the galaxies.