Big planet orbiting a small star: Scientists discover rare pairing in Milky Way galaxy

Astronomers say they have discovered a massive planet orbiting a tiny star, a bizarre pairing that has stumped scientists (Image credit: X/AFP)

Astronomers on Wednesday have discovered a huge planet orbiting a tiny star. This bizarre pairing has left the scientists puzzled. The small star is called TOI-6894. Most stars in the Milky Way galaxy are small like TOI-6894. It is a red dwarf with only about 20 per cent of the Sun’s mass. Scientists never thought that such tiny stars could support massive planets.However, a team of international astronomers found clear signs of a gas giant planet orbiting the small star TOI-6894. Their findings were published in the journal ‘Nature Astronomy’.This discovery makes TOI-6894 the smallest known star to host such a large planet.The planet has a slightly larger radius than Saturn, but weighs only half its mass. It orbits the star very quickly- once every three days. The astronomers discovered the planet while observing more than 91,000 small red dwarf stars from Nasa’s TESS space telescope. The existence of the planet was confirmed by ground-based telescopes including Chile’s observatory ‘Very Large Telescope’. “The fact that this star hosts a giant planet has big implications for the total number of giant planets we estimate exist in our galaxy,” said study co-author Daniel Bayliss from the UK’s Warwick University. Another co-author, Vincent Van Eylen from University College London, said it was an “intriguing discovery”.“We don’t really understand how a star with so little mass can form such a massive planet!” Eylen said.“This is one of the goals of the search for more exoplanets. By finding planetary systems different from our solar system, we can test our models and better understand how our own solar system formed”, he added. Scientists hope discoveries like this one will help them better understand how planets — including those in our own solar system — are formed.

Why is TOI-6894b special?

The new planet, named TOI-6894b is special because it is much cooler than most other planets found outside our solar system. The researchers explained that most of the planets are hot, having temperatures more than 1,000°C. However, the newly discovered planet appears to be under 150°C.That cooler temperature means scientists might be able to detect chemicals like ammonia in its atmosphere — something never seen before in planets outside our solar system.The James Webb Space Telescope is expected to observe this planet in the next year, which can help scientists in uncovering more mysteries of this strange planet.