A international team of scientists, in which researchers from the Canary Islands Astrophysics Institute (IAC) together with other institutions from Spain, Italy, Germany, Belgium, United Kingdom and Mexico, has been able to measure the masses of the giant planets of the V1298 Tau system, of barely 20 million years old. Until now, no data had been obtained on the masses of such young giant planets. The recent finding shows that this type of object has already reached its final size in very early stages of its evolution. The study used measures of radial velocity of the HARPS-N spectrographs, at Roque de los Muchachos Observatory (ORM), and CARMEN IS, at the Calar Alto Observatory. The results are published today in the journal Nature Astronomy.
The study, led by the IAC researcher Alejandro Suarez Mascareño, has been able to measure the masses of the giant planets that orbit the young solar-type star V1298 Tau, showing that they are similar to those of the giant planets of the Solar System or of other known systems that are in their maturity. These measurements are the first to be obtained of such young giant planets.
“The characterization of very young planets is extraordinarily difficult,” says Alejandro Suárez Mascareño, first author of the publication. Its stars have very high levels of activity and until very recently it was unthinkable to even try ”. And he adds: “Only thanks to the combination of detections made with space telescopes, combined with intense radial velocity campaigns, and the use of the most advanced analysis techniques, it is possible to begin to see what is happening in such early stages of the evolution of planetary systems ”.
According to the study, the measurement of these masses tests current ideas about the formation of planetary systems; and gives researchers clues about what happened during the infancy of our solar system
The V1298 Tau bye planets, which were discovered by a team led by Trevor David (JPL) using data from NASA’s Kepler space telescope, have orbital periods of 24 and 40 days respectively, and masses similar to that of Jupiter. To measure their masses, it has been necessary to separate the signals generated by these planets from that corresponding to the star’s activity, almost ten times greater.
According to the study, the measurement of these masses tests current ideas about the formation of planetary systems. “For many years, theoretical models have dictated that giant planets begin their evolution as bodies with a larger size, to later contract over hundreds or even billions of years”, explains Víctor J. Sánchez Béjar, researcher from the IAC and co-author of the work. “Now we know that they can actually reach a size similar to that of the planets in the Solar System in a very short time,” he says.
The study of young systems gives researchers clues about what happened during the infancy of our solar system. “We still do not know if V1298 Tau is a normal case and its evolution is similar to that of most planets or if we are facing an exceptional case; if this were the normal scenario, it would mean that the evolution of planets like Jupiter and Saturn could have been very different from what we think ”, comments Nicolas Lodieu, IAC researcher and also co-author of the work. The results of this work help to build a more solid idea of the early evolution of planetary systems like ours.
To achieve the measurement of these masses, the study has required a significant observational effort and the collaboration of multiple observatories and institutions from different countries. Radial velocity measurements have been combined from various instruments such as the ultra-stable high-resolution HARPS-N spectrograph, installed at the Nazionale Galileo Telescope (TNG) of the Roque de los Muchachos Observatory; the CARMENES high-resolution spectrograph, at the Calar Alto observatory; the HERMES spectrograph, at the Mercator telescope, also at the ORM; and the SES spectrograph, installed in the STELLA telescope at the Teide Observatory. Observations taken from the Las Cumbres Observatory, a network of telescopes located around the world, have been used to continuously monitor the variations of the star’s activity.
In addition to the researchers Alejandro Suárez Mascareño, Victor J. Sánchez Béjar and Nicolas Lodieu, from the IAC the researchers Rafael Rebolo López, Felipe Murgas, Jonay González Hernández, Carlos Cardona Guillén, Borja Toledo Padrón, Patricia Chinchilla, have also collaborated in this publication. Emma Esparza Borges, Mahmoud Oshagh, Enric Pallé and Hannu Parviainen.