One of the oldest stars has been discovered in the milky way hosting a hot rocky super earth. Scientists believe that after Big Bang, the universe consisted of lightweight elements like Hydrogen, Helium and traces of Lithium indicating only gaseous planets could be formed in the beginning. So it’s unlikely for a 10 billion old star hosting a rocky planet.
The star is named TOI-561 and the planet TOI-561b. these 2 are found in the thick disk region of the milky way which is known to be about 10 billion years old. Heavy elements like carbon, iron and magnesium are required to form a rocky planet.
These metals are formed through fusion reactions in the heart of stars and expelled when a star dies in a supernova explosion. After release, the elements continue the great circle of life. So around 10 billion years ago, such elements weren’t really in abundance. This new planet has density similar to our planet Earth. However, TOI-561 hosts 2 other gaseous planets in addition to this planet. This is making scientists confused.
The NASA’s test mission an exoplanet hunting telescope using transit method to collect data on planets and researchers from W.M. Keck Observatory in Hawaii discovered the planet, identifying it as super earth since it’s mass is 1.6 of Earths with a 1.4 times larger radius. Team at Keck observatory was able to measure the planet’s mass using a customized instrument collecting information during the transit method. Using a High-Resolution Echelle Spectrometer(HIRES), astronomers can measure the wobble in a star with the planet’s gravitational pull.
However, it’s orbital period is less than 12 hours. This makes the exoplanet very close to it’s host star whose surface temperature is high enough(~1,226 degree celcius)to eliminate the chances of any life. TOI-561b provides may prove helpful to identify elements present during the very beginning of the universe and the origin of the old stars in the galaxy thick disk.
This discovery proves the chances of existence of other ancient rocky planets within the galaxy helping us to understand the building blocks of the universe.