View of the young star HD 163296, with the newly discovered whirlpool or a ‘whirlpool’ of dust and stones revolving around it. According to the researchers, a new planet is forming in the brightest region, where pebbles are ground to form warmer 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 many of these protoplanetary disks, and they can often see concentric gaps in the disks, such as grooves on an old vinyl gramophone record. It is in the gaps that planets form from gas and dust that merge. On 21 January 2021, an international group of scientists, led by researchers in the Netherlands, announced that they had done so zoomed in a little more and find what they think a planet is in the process of forming in its own vortex or dust of rocks. That is, they see not only a gap in a disk, but also a real world born within its own planet-forming maelstrom. The discovery was made using the new MATISSE instrument, which combines light and analyzes from four separate telescopes at the ESO Observatory’s Very Large Telescope (VLT) at Cerro Paranal, in northern Chile.
The discovery was announced by Astronomy.nl on January 21, 2021 and a paper is pending but not yet published. However, a free version of the pre-print is available at arXiv.
The major 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 gaps of the disk. Image via 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 twice as massive as our sun.
The star has been extensively studied by astronomers, but the researchers, led by József Varga at Leiden University in the Netherlands, wanted to take a closer look at the inner part of the disk around the star. They did so in March and June 2019 and saw something interesting: a smaller ring of warm, fine dust orbiting the star, at about the same distance as Mercury is from our sun.
Could this be where a planet forms? According to the researchers, this is probably exactly what it is, as they noticed something different on the ring: one part of it was much brighter and warmer than the rest of it and saw bright white-yellow in the photos.
According to the researchers, this bright region is a vortex, ie. the whirlwind, where a planet gradually forms right before our eyes.
The artist’s concept of young protoplanets forming in the protoplanetary disk around a star. Image via NRAO / AUI / NSF / S. Dagnello / Scientific news.
Why does this vortex look so bright? According to scientists, rocky pebbles are ground to fine dust, which produces more heat. It’s a little different from other places on the disk, where the pebbles just clump together.
The planets in our own solar system, including the Earth, began their lives in the same way as dust, pebbles, and gas flowed together, eventually creating rocky, icy, and gaseous. worlds.
The MATISSE instrument is powerful; by combining the light of 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 the infrared radiation of stars. Since dust disks and planets emit this type of radiation, MATISSE can detect it by analyzing the amount of radiation emitted.
József Varga at Leiden University in the Netherlands, lead author of the new study. Image via Leiden University.
It is already known that HD 163296 has three other giant young planets in wide orbits. Like the latest discovery, these planets are babies that have not yet been 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 live within the gaps in the main protoplanetary disk that surrounds the star. These planets were discovered by two teams of astronomers measuring the flow of gas inside the disk. According to Christophe Pinte, an astronomer at Monash University in Australia:
Measuring the flow of gas inside a protoplanetary disk gives us much more certainty that planets are present around a young star. This technique offers a promising new direction to understand how planetary systems form.
The astronomer Richard Teague of the University of Michigan, leader of the second team, added:
We looked at the localized, small-scale motion of gas in the star’s protoplanetary disk. This completely new approach can expose some of the latest planets in our Milky Way galaxy, all thanks to the high-resolution images of ALMA.
The MATISSE instrument on ESO’s Very Large Telescope Interferometer (VLTI). Image via ESO / P. Horalek / Astronomie.nl.
This latest and smaller planet, if confirmed, would be the fourth in this system.
The researchers now want to make similar observations of other stars with protoplanetary disks, especially those that may contain evolving rocky planets such as Earth. This would provide important clues as to how our own world was born and developed.
In short: international researchers, led by a team in the Netherlands, have discovered a possible newborn planet that forms in a “whirlwind” of dust and rocks around a young star.
Source: The asymmetrical inner disk of the Herbig Ae star HD 163296 in the eyes of VLTI / MATISSE: evidence for a vortex?
Via Astronomie.nl
Via Sci-News
