Astronomers find the possible ‘brother’ of a planet orbiting a distant star with ‘SOUL’

July 19 () –

Astronomers have found the possible ‘sister’ to a planet orbiting a distant star by using the ‘Atacama Large Millimeter/submillimeter Array’ (ALMA), as reported by the European Southern Observatory (ESO).

Specifically, the team has detected a cloud of debris that could be sharing the orbit of this planet and believe that they could be the basic components of a new planet or the remains of one already formed.

“Two decades ago it was theoretically predicted that pairs of planets of similar mass could share the same orbit around their star, the so-called Trojan or co-orbital planets. For the first time, we have found evidence in favor of that idea.”said the student at the Center for Astrobiology in Madrid, Olga Balsalobre-Ruza.

Specifically, an international team of scientists has used ‘ALMA’ to find that there could be Trojan planets in the ‘PDS 70’ system. This star is known to host two giant Jupiter-like planets, ‘PDS 70b’ and ‘PDS 70c’. In this regard, by analyzing archival ALMA observations of this system, the team detected a cloud of debris at the location of PDS 70b’s orbit where Trojans are expected to exist.

According to experts, the Trojans occupy so-called ‘Lagrangian’ zones, two extended regions in a planet’s orbit where the combined gravitational pull of the star and planet can trap material. In this way, they have explained that when studying these two regions of the orbit of ‘PDS 70b’, they detected a “weak” signal from one of themindicating that a cloud of debris with a mass about twice the Moon could reside.

The team believes that this cloud of debris could point to an existing Trojan world in this system, or to a planet in the process of forming. “Who could imagine two worlds that share the length of the year and the conditions of habitability? Our work is the first evidence that this type of world could exist. We can imagine that a planet can share its orbit with thousands of asteroids as in the case of Jupiter, but I am surprised that the planets can share the same orbit”, Balsalobre-Ruza pointed out.

“It opens new questions about the formation of Trojans, how they evolve and how frequent they are in different planetary systems.“, added the director of the ESO Office for Science in Chile, Itziar De Gregorio-Monsalvo.

To fully confirm its detection, the organization has noted that the team will have to wait until after 2026, when it will use ALMA to see if both PDS 70b and its sister debris cloud move significantly along in their orbit around the star. . “This would be a great advance in the exoplanetary field,” said Balsalobre-Ruza.

“The future of this topic is very exciting and we look forward to the expanded capabilities of ‘ALMA’, planned for 2030, which will dramatically improve the matrix’s ability to characterize Trojans on many other stars.“, has pointed out De Gregorio-Monsalvo.

TROJAN HORSES: COMMON IN THE SOLAR SYSTEM

According to the astronomical organization, Trojans, which are rocky bodies in the same orbit as a planet, are common in the Solar System. In this sense, he has explained as an example the Trojan asteroids of Jupiter, which are more than 12,000 rocky bodies that are in the same orbit around the Sun.

Astronomers have predicted that Trojans, particularly Trojan planets, could also exist around a star other than the Sun, but say the evidence is “scant.”

“Exotrojans (Trojan planets outside the Solar System) have so far been like unicorns, they are allowed to exist in theory, but no one has ever detected them.” explained the co-author and principal investigator of the Center for Astrobiology, Jorge Lillo-Box.