51 Eridani b: NASA discover young ‘alien Jupiter’ planet

Still glowing with the heat of its formation, this young planet orbits a star that is only 20 million years old, a toddler in astronomy terms.

51 Eridani b is around 600 times bigger than Earth and has an average temperature of 1,200 degrees Fahrenheit (650 degrees Celsius), with an atmosphere composed of water and methane. It is said to be similar to one our own Solar System’s planets, Jupiter.

Discovery image of the planet 51 Eridani b with the Gemini Planet Imager taken in the near-infrared light. The bright central star has been mostly removed to enable the detection of the exoplanet one million times fainter. J. Rameau (UdeM) and C. Marois (NRC Herzberg)

The huge heat that this planet produces is a result of the energy captured during its formation, which is thought to have taken place at a similar time to its star’s formation. The instrument responsible for its discovery was The Gemini Planet Imager (GPI), which was also able to measure the large quantities of methane in its atmosphere. The young age of this planet is very important to scientists, it means that it will still exhibit signs of how it was formed. There are two prevailing theories related to the formation of gas giants. They can form quickly when material rapidly combines into a hot, mixed ball of gas and solid material. This is contrary to the way scientists believe Jupiter formed, which began with the gradual build up of a rocky core before the gaseous outer layers were trapped to complete the planet’s formation. If this process becomes too slow the gaseous layers may never form, which could result in a rocky planet much like Earth.

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