The closest star system to Earth: Alpha Centauri
Situated around 4 light years away, Alpha Centauri is the closest star-system to the Solar System. To read more about the Solar System, click here. In the night sky, this star system looks like a single star to the naked eye, but is actually triplets. It takes a powerful telescope and a lot of patience to find the difference between the three stars.
Two sun-like stars, Alpha Centauri A and Alpha Centauri B orbit a common centre about once every 80 years and are separated by around 23 Astronomical Units or AU(The average distance between the Earth and the Sun about 150 million km or 93 million miles). There is also a third fainter star, called Proxima Centauri which orbits the other two but at a huge distance from them. Scientists think that it takes Proxima Centauri about a million years to orbit the other two stars. Out of these three stars, Proxima Centauri is the nearest to the Earth.
Alpha A is a yellow star, very similar to our sun but brighter and slightly more massive.Scientists think that the Alpha Centauri system formed 1000 million years before our Solar System. Both Alpha A and Alpha B are stable stars and may have been born surrounded by planet forming disks.
In 2008, scientists suggested that planets may have formed around Alpha A and Alpha B. Since then, they are monitoring Alpha Centauri to see whether small wobbles in Starlight will show us exoplanets around these stars.
Alpha Centauri can be seen from the Earth's southern hemisphere, where it is a part of the Centaurus constellation. Its proper name - Rigel Kentaurus - means 'centaur's foot'.
Alpha A and Alpha B are binary stars. This means that if you were standing on any one of them at particular times, you would be able to see both of them in the sky. It would be like having two suns in the sky!
The first exoplanet discovered in Alpha Centauri was orbiting Proxima Centauri. It is called Proxima - b. You can read more about it here.
Recently, a second exoplanet was discovered in 2020 and scientists predict that it could have a mass about 7 times that of the Earth.
That is all for this post on Alpha Centauri. Hope you found it informative and easy to understand. For any suggestions/reviews, you can contact us by filling the contact form on the right or you can comment down below. Please follow this blog for more mindblowing facts about space and the Universe.
Regards,
Aarav Iyer
References:
(1) Unlocking The Universe by Stephen and Lucy Hawking