New images could unlock the mysteries of how giant planets are born

A composite image made from observations by different telescopes supports theories of how planets as big as Jupiter form.

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Published: July 25, 2023 at 1:00 pm

Five thousand light-years away in the Monoceros constellation, strange materials are swirling around a young star known as V960 Mon.

Astronomers were baffled when the star’s brightness rapidly increased by over 20 times back in 2014. Now, observations published in The Astrophysical Journal Letters have helped to explain the secrets behind these events in fascinating detail.

New images reveal large, dusty ‘clumps’ as large as planets gathering around the star. If these collapse, they could form giant planets as massive as Jupiter.

“This discovery is truly captivating,” said Dr Alice Zurlo of the Universidad Diego Portales, Chile, a researcher involved in the observations.

The images, released by the European Southern Observatory (ESO), show that the material orbiting the star is assembling into spiral ‘arms’ that extend over distances bigger than our entire Solar System.

SPHERE and ALMA images of material orbiting V960 Mon
The composite image of V960 Mon is here split into its original parts. Observations from the Very Large Telescope (VLT) are shown on the left in yellow, revealing the dusty material around the star assembling in spiral ‘arms’. The blue regions represent the data from the Atacama Large Millimeter/submillimeter Array (ALMA) which looks deeper into the structure of the arms and shows the large clumps that could collapse to form giant planets © ESO/ALMA (ESO/NAOJ/NRAO)/Weber et al.

These formations were detected using the creatively named Very Large Telescope (VLT) and the Atacama Large Millimeter/submillimeter Array (ALMA), which probe around the surface of the spiral arms as well as deep into their intricate structures.

The observations could help astronomers learn more about the secrets behind the formation of large planets. Currently there are two theories as to how this happens.

The first is called core accretion, which is essentially when dust grains join together. The second is gravitational instability, which involves large material around a star contracting and collapsing into a planet. The clumps around V960 Mon could provide evidence of this second theory, which so far has had limited support.

“Our group has been searching for signs of how planets form for over ten years, and we couldn't be more thrilled about this incredible discovery,” said Sebastián Pérez, one of the researchers from the University of Santiago, Chile.

As if the Very Large Telescope wasn’t enough, the ESO is currently building an Extremely Large Telescope (ELT) in the Atacama Desert in Chile. This will allow the astronomers to observe the system in even greater detail, including the chemical compositions of the forming planets.

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