View of the young star HD 163296, with the newly discovered vortex or “whirlwind” of dust and pebbles revolving around it. Researchers believe that a new planet is forming in the brightest region, where pebbles are ground to form warmer dust. Image by J. Varga et al. Astronomie.nl.
Planets are born in massive disks of gas and dust around newly formed stars. Astronomers have observed many of these protoplanetary disks and can often see concentric gaps in the disks, like ditches on an old vinyl phonograph disk. In those voids, the planets form from gas and dust that coalesc together. On January 21, 2021, an international group of scientists, led by researchers in the Netherlands, announced that they had done so. enlarged something more and they discovered what they believe to be a planet forming inside their own vortex or vortex of dust and pebbles. That is, they see not only a gap in a disk, but a real world that is born in its own maelstrom of planet formation. The discovery was made using the new MATISSE instrument, which combines and analyzes light from four telescopes separated from the very large telescope (VLT) of the ESO Observatory on Cerro Paranal in northern Chile.
The discovery was announced by Astronomy.nl on January 21, 2021, and a paper is pending, but has not yet been published. However, a free pre-print version is available at arXiv.
The main protoplanetary disk of dust, pebbles and gas surrounds the young star HD 163296. Three other giant planets are also known to form in the hollows of the disk. Image by ALMA / ESO / NAOJ / NRAO / AUI / NSF / A. Isella / B. Saxton / Scientific news.
The young star, HD 163296, is about 330 light-years from Earth in the constellation Sagittarius. It is only about four million years old and is twice as big as our sun.
The star has already been extensively studied by astronomers, but researchers led by József Varga of Leiden University in the Netherlands wanted to take a closer look at the inner disk surrounding the star. They did this in March and June 2019 and saw something interesting: a smaller ring of warm, fine dust orbiting the star, about the same distance as Mercury is from our sun.
Could it be where a planet is forming? The researchers say that this is probably exactly what it is, since they noticed something else about the ring: part of it was much brighter and hotter than the rest, appearing in bright white-yellow in the images.
According to researchers, this bright region is a whirlwind, that is. the whirlpool, where a planet gradually forms right in front of our eyes.
The artist’s concept of young protoplanets forming in the protoplanetary disk around a star. Image by NRAO / AUI / NSF / S. Dagnello / Scientific news.
Why does this whirlpool look so bright? Scientists say that where the pebbles are ground into fine dust, producing more heat. This is a little different from the other places on the disk, where the pebbles crowd.
The planets in our own solar system, including Earth, began their life in the same way, while dust, pebbles, and gas allied together, eventually creating rocks, ice, and gas. lights.
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. Because 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 huge young planets in wide orbits. Like the latest discovery, these planets are babies, they are 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 are in the gaps in the main protoplanetary disk that surrounds the star. These planets were discovered by two teams of astronomers who measure the flow of gas inside the disk. According to Christophe Pinte, an 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 a promising new direction for understanding how planetary systems are formed.
University of Michigan astronomer Richard Teague, the leader of the second team, added:
We looked at the localized, small-scale motion of the gas in the star’s protoplanetary disk. This completely new approach could discover 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 by ESO / P. Horalek / Astronomie.nl.
This new and smaller 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, such as Earth. This would provide important clues as to how our own world was born and evolved.
Conclusion: International researchers, led by a team from the Netherlands, have discovered a possible newborn planet that forms in a “whirlwind” of dust and pebbles around a young star.
Source: Herbig Ae HD 163296 asymmetric inner disk in VLTI / MATISSE eyes: evidence for a vortex?
Via Astronomie.nl
Via Sci-News
