ALMA captures the birth of the planets first hand

In 2013,Atacama Large Millimeter/Submillimeter Array (Large Millimeter/Submillimeter Grid of Atacama-ALMA) on the high Chajnantor Plateau, 5,000 meters above sea level, is one of the highest astronomical observatories on Earth in the Chilean Andes. ALMA is a network of radio telescopes capable of observing some of the coldest objects in the universe in radiation bands called millimeter and sub-millimeter, i.e. ranging from infrared to radio waves.

This allows Alma to explore the mysteries of planetary birth in protoplanetary disks where planets form according to standard cosmogony. These disks are first produced by the accumulation of gas and dust in a cold, dense molecular cloud that can collapse under their own gravity, forming a protostar as the pressure heats the material to eventually ignite thermonuclear fusion reactions.

ESOcast 69 presents the results of ALMA observations that reveal extremely fine details never before seen in the planet-forming disk around the young star HL Tauri. This is the sharpest image ever taken at sub-millimeter wavelengths. For a fairly accurate French translation, click on the white rectangle at the bottom right. Look for the English translation to appear and finally click “Translate automatically.” Select “French”. © European Southern Observatory (ESO)

From HL Tauri to DG Tau

So, for about a decade, Alma has been providing us with images of these records at different periods of their development. As shown in the video above, dust in protoplanetary disks sticks together to produce pebbles and blocks of rock more than a meter long that will attract each other to form small planetary bodies and planetary embryos that grow in size and will produce gas-poor regions. And dust in its orbits.

But if we believe an international team of astronomers led by Satoshi Ohashi of the National Astronomical Observatory of Japan (NAOG), it has enabled ALMA to delve deeper into the past of the origin of the solar system’s planets or known planets. Exoplanets in the Milky Way by observing a protostar named DG Taurus (DG Tau).

Just like HL Tauri, it is located in the famous Taurus Molecular Cloud 1 (TMC-1). Taurus molecular cloud 1) It is located about 450 light-years from Earth in the constellation Taurus.

In an article published in Astrophysical Journal, But it can also be read freely arXivThe researchers explain that, unlike HL Tauri, the protoplanetary disk of DG Tau appears smooth and without ring structures associated with currently forming planets. This is a remarkable discovery because finding a blank disc without such signatures has so far proven difficult.

Cosmogony models for review

Planetary cosmogonists conclude that we may observe the protoplanetary disk of DG Tau at the very beginning of planetary birth, and thus is an open window into the cosmic physical and chemical mechanisms at work. . ” There is no evidence of planet formation. We believe that this study is very important because it reveals the initial conditions for the formation of the planet Satoshi Ohashi commented in a press release issued by Naoj which states, “ The results interestingly suggest that the outer regions of the disk are the likely starting point for planet formation, challenging previous beliefs that the inner disk was the primary starting point. It is worth noting that the middle plane of the disk has a high dust/gas ratio, indicating that the disk will soon be ready for planetary formation “.

To uncover these secrets, astronomers observed the disk at different wavelengths (0.87 mm, 1.3 mm, 3.1 mm) and studied the intensity and polarization of radio waves. Depending on the size and density of the dust, the ratio of the intensity of radio waves at different wavelengths and the intensity of polarization of radio waves scattered by the dust changes. The size and density distributions of dust grains can then be estimated by comparing the results of numerical simulation observations with different models of the size and density distribution of dust in the protoplanetary disk around the protostar.

https://www.youtube.com/watch?v=4Cs6qU Hz3yA

The solar system is a laboratory for studying the formation of giant planets and the origin of life that can be used along with the rest of the universe and can be observed for the same purpose. MOJO: Modeling the Origin of the Jupiters is a research project that has resulted in a series of videos presenting the theory of the origin of the solar system and in particular the gas giants by two renowned specialists, Alessandro Morbidelli and Sean Raymond. For a fairly accurate French translation, click on the white rectangle at the bottom right. The English translation should appear next. Then click on the nut to the right of the rectangle, then on “Translations” and finally on “Translate automatically.” Select “French”. © Lawrence Honorat