A newly found giant exoplanet around a tiny star is challenging our understanding of how planets form
An anomalous planetary body or maybe even two have been found around the red dwarf GJ 3512, the most common type of star in our galaxy. They are 30 light-years away from us and according to current theories they ‘should not exist’.
How did the unusual planet form?
The international team of astronomers believe that the planet probably formed from an unstable disc around the young star which broke up into clumps. They argue that the discs around small stars don’t provide enough material for the current theories to work. This consists of the disk instability model of planet formation.
What do our current theories dictate?
The formation of the exoplanet does not fit with how the majority of the planets are believed to have formed. Computational simulations point to the fact that planets grow from nebulas (a cloud of dust and gas) into solid cores.
“Usually we think of giant planets starting life as an icy-core, orbiting far out in a disc of gas surrounding the young star, and then growing rapidly by attracting gas on to itself,” said Prof Wheatly.
How was it found?
The study was first published by the CARMENES consortium led by IEEC researches. They used telescopes from Spain and the US and signals from the extraordinary planetary system were picked up using visible and infrared arms of their spectrographs at the Calar Alto Observatory. For this discovery, CARMENES also used IEEC’s 80cm diameter Joan Oró Telescope at the Montsec Observatory, the facilities at Observatorio de Sierra Nevada and Las Cumbres Observatory in California.
Scientists used the Doppler technique, monitoring the back and form motion of a star when it was orbited by one or more planets. They made the discovery of this exoplanet solely using a new generation near-infrared precision instrument, highlighting the leading role played by European researchers in the field of exoplanets.
What does this discovery mean for us?
“I find it fascinating how a single anomalous observation has the potential to produce a paradigm shift in our thinking, in something as essential as the formation of planets and, therefore, in the big picture of how our Solar System came into existence,” declares Juan Carlos Morales, a researcher from the Institute of Space Studies of Catalonia at the Institute of Space Sciences.
Image credit: Guillem Anglada-Escude – IEEC/Science-wave, using SpaceEngine.org, Creative Commons Attribution 4.0 International (CC BY 4.0).