A study published on Tuesday revealed that a group of astronomers have discovered the smallest star of the known universe. The star, EBLM J0555-57Ab, is 600 light years away from earth, inside our very own galaxy- the Milky way.
The lead author of the study Alexander von Boetticher who is a graduate student at the University of Cambridge in the United Kingdom, said: “Our discovery reveals how small stars can be”.
According to the study, EBLM J0555-57Ab is most probably the smallest a star can ever be. This is because, had the mass of the star been any lesser, the pressure at the core would be too low, and as a result, the hydrogen fusion process would not occur. The fusion process is essential to stars at it produces light and heat. Stars incapable of the process turn into a brown dwarf which also known as failed stars.
EBLM J0555-57Ab has a gravitational pull that is around 300 times greater than earth’s and its radius is slightly larger than Saturns. It is about 2000 to 3000 times dimmer than our own Sun and it is part of a binary system in which it orbits around a much larger star.
The star was found when it passed in front of its much larger companion. The technique used to detect it is known as the transit method. The method is typically used to discover exoplanets i.e. planets that are outside our solar system. Astronomers discovered properties of the stars such as its mass Using Doppler spectroscopy. A method which measures the wobble of the primary star caused by the gravitational pull of its orbiting neighbour.
Lead author Von Boetticher said “This star is smaller and likely colder than many of the gas giant exoplanets that have so far been identified,”
EBLM J0555-57Ab may have only just qualified as a star, yet, there is a high possibility of an Earth-like planet existing near it. This is because smaller and dimmer stars are naturally colder thus planets around them have a greater chance of preserving water, and therefore a greater chance of sustaining life.
Understanding small stars can be quite a challenge. Nevertheless, astronomers will continue to research the star, as the discovery could have some promising implications. Whether the discovery will lead to something bigger is something we cannot predict, nevertheless anything that further deepens our understanding of the universe is always fascinating.