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View of the young star HD 163296, with the recently discovered vortex or “vortex” of dust and pebbles surrounding it. Researchers believe a new planet is forming in the brighter region, where pebbles are crushed to form hotter dust. Image via J. Varga et al./ Astronomie.nl.
Planets are born in massive swirling disks of gas and dust around newly formed stars. Astronomers have observed several of these protoplanetary discs, and often they can see concentric spaces in the discs, like grooves on an old vinyl phonograph record. It is in these gaps that the planets form from the fusion of gas and dust. On January 21, 2021, an international group of scientists, led by researchers in the Netherlands, announced that they had Zoomed a little more and found what they think is a planet forming inside its own vortex or vortex of dust and pebbles. In other words, they not only see a gap in a disk, but a real world being born in its own maelstrom forming a planet. The discovery was made using the new MATISSE instrument, which combines and analyzes light from four separate telescopes at the Very Large Telescope (VLT) at ESO’s Observatory on Cerro Paranal in northern Chile.
The discovery was announced by Astronomy.nl January 21, 2021, and an article is pending, but not yet published. A free pre-print version is however available from arXiv.
The main protoplanetary disk of dust, pebbles and gas surrounds young star HD 163296. Three other giant planets are also known to form in the interstices of the disk. Image via ALMA / ESO / NAOJ / NRAO / AUI / NSF / A. Isella / B.Saxton / Sci News.
The young star, HD 163296, is approximately 330 light years from Earth, in the constellation Sagittarius. It is only about four million years old and twice as massive as our sun.
The star has already been studied extensively by astronomers, but the researchers, led by József Varga from the University of Leiden in the Netherlands, wanted to take a closer look at the inner part of the disc surrounding the star. They did this in March and June 2019 and saw something interesting: a small ring of hot, fine dust orbiting the star, roughly the same distance Mercury is from our sun.
Could this be where a planet forms? The researchers say that’s probably exactly what it is, as they noticed something else about the ring: Part of it was much brighter and warmer than the rest, appearing a whitish yellow. shiny on the images taken.
According to the researchers, this bright region is a vortex, ie. the vortex, where a planet is gradually forming before our eyes.
Artist’s concept of young protoplanets forming in the protoplanetary disc around a star. Image via NRAO / AUI / NSF / S. Dagnello / Sci News.
Why is this vortex so bright? Scientists say this is where rock pebbles are crushed into fine dust, producing more heat. It’s a little different from other places on the disc, where the pebbles stick together.
The planets in our own solar system, including Earth, began life in much the same way, as dust, pebbles and gas coalesced, ultimately creating real rocks, icy and gaseous. worlds.
The MATISSE instrument is powerful; by combining the light from the four telescopes, it creates the equivalent of a single telescope with a virtual diameter of 200 meters (656 feet). Its main mission is to analyze infrared radiation from stars. Since dust disks and planets emit this type of radiation, MATISSE can detect them by analyzing the amount of radiation emitted.
József Varga from Leiden University in the Netherlands, lead author of the new study. Image via Leiden University.
HD 163296 is already known to have three other young giant planets in wide orbits. Like the latest discovery, these planets are babies, not yet fully formed. Their discovery, made by the Atacama Large Millimeter / submillimeter Array (ALMA) observatory, was announced in 2018. Like other protoplanets, as they are called, they reside in the interstices of the main protoplanetary disk surrounding the star. These planets were discovered by two teams of astronomers measuring the flow of gas inside the disc. According to Christophe Pinte, astronomer at Monash University in Australia:
Measuring the flow of gas in a protoplanetary disk gives us much more certainty that the planets are present around a young star. This technique offers promising new direction for understanding how planetary systems are formed.
University of Michigan astronomer Richard Teague, leader of the second team, added:
We examined the localized and small-scale movement of gas in the star’s protoplanetary disk. This entirely new approach could uncover some of the youngest planets in our Milky Way galaxy, all thanks to high-resolution images from ALMA.
The MATISSE instrument on ESO’s Very Large Telescope Interferometer (VLTI). Image via ESO / P. Horalek / Astronomie.nl.
This newest and smallest planet, if confirmed, would be the fourth in this system.
Researchers now want to make similar observations of other stars with protoplanetary disks, especially those that may contain developing rocky planets like Earth. This would provide important clues as to how our own world came into being and evolved.
Conclusion: international researchers, led by a team in the Netherlands, have discovered a possible newborn planet forming in a “vortex” of dust and pebbles around a young star.
Source: The asymmetric internal disk of the star Herbig Ae HD 163296 in the eyes of VLTI / MATISSE: evidence of a vortex?
Via Astronomie.nl
Via Sci-News
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