View of the young HD star 163296, with the newly discovered whirlpool or “swirl” of dust and pebbles circling around it. Researchers think a new planet is forming in the brighter region, where pebbles are grinding to form warmer dust. Image through J. Varga et al./ Astronomie.nl.
Planets are born in massive swirling 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, such as slots on an old vinyl phonograph disk. It is in these voids that the planets are formed from the gas and dust that come together. On January 21, 2021, an international group of scientists, led by researchers from the Netherlands, announced that it has done so. expanded a little more and they found what they think is a planet in the process of formation within its own vortex or vortex of dust and pebbles. That is, not only do they see a void in a disk, but a real world is born within their own planet-forming vortex. The discovery was made with the new MATISSE instrument, which combines and analyzes the light of four separate telescopes in 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 there is a document pending but not yet published. However, a free prepress version is available on arXiv.
The main protoplanetary disk of dust, pebbles and gas surrounds the young star HD 163296. It is also known that three other giant planets form within the hollows of the disk. Image via ALMA / ESO / NAOJ / NRAO / AUI / NSF / A. Isella / B. Saxton / Sci-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 massive as our sun.
The star has already been extensively studied by astronomers, but researchers, led by József Varga at Leiden University in the Netherlands, wanted to delve deeper into the inner part of the disk surrounding the star. They did so 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 this be where a planet is formed? The researchers say this is probably exactly what it is, as they noticed something else about the ring: one part was much brighter and warmer than the rest, and it appeared bright whitish yellow in the images taken.
According to the researchers, this bright region is a vortex, that is. the whirlpool, where a planet is gradually formed right before our eyes.
Artist concept of young protoplanets forming on the protoplanetary disk around a star. Image via NRAO / AUI / NSF / S. Dagnello / Sci-News.
Why does this vortex look so bright? Scientists say it is where fine powder rock pebbles are cemented and produce more heat. This is a bit different from other places on the disk, where the pebbles are just grouped together.
The planets in our own solar system, including Earth, began their life in the same way, as dust, pebbles, and gas fused, eventually creating rocks, ice, and gas. mons.
The MATISSE instrument is powerful; by combining the light from the four telescopes, the equivalent of a single telescope with a virtual diameter of 200 meters (656 feet) is created. Its main mission is to analyze the infrared radiation that comes from the stars. Since dust disks and planets emit this type of radiation, MATISSE can detect them by analyzing the amount of radiation emitted.
József Varga at Leiden University in the Netherlands, lead author of the new study. Image through Leiden University.
HD 163296 is already known to have three other young giant planets in wide orbits. Like the new discovery, these planets are babies, they are not yet fully formed. Its discovery, made by the Atacama Large Millimeter / submillimeter Array (ALMA) observatory, was announced in 2018. Like other protoplanets, as they are called, they reside within the voids of the main protoplanetary disk surrounding the star. These planets were discovered by two teams of astronomers who measured the flow of gas inside the disk. According to Christophe Pinte, astronomer at Monash University in Australia:
Measuring the flow of gas within a protoplanetary disk gives us much more certainty that 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, second team leader, added:
We observed the small-scale localized motion of the gas on the protoplanetary disk of the star. This completely 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 of the ESO very large telescope interferometer (VLTI). Image via ESO / P. Horalek / Astronomie.nl.
This newer and smaller planet, if confirmed, would be the fourth in this system.
Now researchers want to make similar observations of other stars with protoplanetary disks, particularly those that may contain developing rocky planets like Earth. This would provide important clues as to how our own world was born and evolved.
Summary: International researchers, led by a team in the Netherlands, have discovered a possible newborn planet that forms in a “swirl” of dust and pebbles around a young star.
Source: The asymmetrical inner disk of the star Herbig Ae HD 163296 in the eyes of VLTI / MATISSE: evidence of a vortex?
Via Astronomie.nl
Via Sci-News
