“SMSS J031300.36-670839.3”: Oldest known star in the Universe discovered

The astronomers led by Dr Stefan Keller of the Australian National University (ANU) have discovered the oldest known star, SMSS J031300.36-670839.3, in the Universe, which formed shortly after the Big Bang 13.6 billion years ago.

• Modern cosmological science stated that our universe came into existence as a result of a Big Bang event about 13.7 billion years ago. Our Sun is approximately 4.57 billion years old.
• The new star beats the previous longevity record of 13.2 billion years set by a star dubbed HD 140283 surveyed by American astronomers.
• The ANU SkyMapper telescope at the Sliding Spring Observatory has discovered the oldest known star in the Universe.

About SMSS J031300.36-670839.3 star

• SMSS stands for SkyMapper Southern Sky Survey, the 031300 refers to the right ascension of the star on the sky and the 670839.3 refers to the declination.
• Second-generation star due to the low level of iron in the upper limit.
• Composition:  Mass 60 times bigger than our Sun and is relatively close to us, about 6,000 light years from the Earth.
• Age: Approximately 13.6 billion years.
• Discovery indicates that the supernovae of first generation stars may not have been as powerful as previously thought.
• Showed the signs of pollution with lighter elements viz. carbon, magnesium, etc, with no traces of iron. This indicates the primordial star’s supernova explosion was of surprisingly low energy. (Previously, primordial stars were thought to have died in violent explosions which polluted space with iron).
• In other words, the extremely low iron content of ‘J’ (to give it a more manageable pseudonym) indicates that the explosion that formed it was relatively low energy.
• Though, sufficient to disintegrate the primordial star, almost all of the heavy elements such as iron, were consumed by a black hole that formed at the heart of the explosion.
• The discovery is the first step in understanding ancient stars that formed after the Big Bang. Astronomers can measure the star’s composition as well as iron “pollution” due to supernovae.

Benefit of the discovery: For the first time, astronomers can study the chemistry of the first stars and can give a clearer idea of what the Universe was like in its infancy.

About Big Bang Theory

The Big Bang is the scientific theory that is most consistent with observations of the past and present states of the universe, and it is widely accepted within the scientific community. It offers a comprehensive explanation for a broad range of observed phenomena, including the abundance of light elements, the cosmic microwave background, large scale structure, and the Hubble diagram.

Note: First generation stars are predominantly tens or hundreds of times more massive than the Sun. They live fast, die young and have not survived to the present day. Though, the second generation stars, a little smaller than the Sun, have massive lifespan of over 13 billion years.

Month: Current Affairs - February, 2014

Category: Science & Technology Current Affairs