protoplanetary disks – Behind The Black

Astronomers detect evidence of numerous protoplanetary disks in three molecular clouds near the galactic center

May 16, 2025 11:58 am Robert Zimmerman

Using the ground-based ALMA telescope in Chile, astronomers have detected evidence of the existence of numerous protoplanetary disks in three molecular clouds near the galactic center.

The findings suggest that over three hundred such systems may already be forming within just these three CMZ clouds [Central Molecular Zone]. “It is exciting that we are detecting possible candidates for protoplanetary disks in the Galactic Centre. The conditions there are very different from our neighbourhood, and this may give us a chance to study planet formation in this extreme environment,” said Professor Peter Schilke at the University of Cologne.

You can read the paper here.

These results once again suggest that the formation of stars, solar systems, and planets is more ubiquitous than ever expected, that they can all form in very extreme and hostile environments, of which the center of the Milky Way is one of the most hostile.

And if planets can form here, they can likely form everywhere else. This increases the likelihood of many planets throughout the galaxy capable of supporting the development of life.

Survey of protoplanetary disks finds their size varies significantly

March 26, 2025 9:02 am Robert Zimmerman

Click for original image.

A survey of the protoplanetary disks in a star-forming region about 400 light years from Earth has found that the size of the disks can vary considerably, with many much smaller than our own solar system.

Using ALMA [Atacama Large Millimeter/submillimeter Array in Chile], the researchers imaged all known protoplanetary discs around young stars in Lupus, a star forming region located about 400 light years from Earth in the southern constellation Lupus. The survey reveals that two-thirds of the 73 discs are small, with an average radius of six astronomical units, this is about the orbit of Jupiter. The smallest disc found was only 0.6 astronomical units in radius, smaller than the orbit of Earth.

…The small discs were primarily found around low-mass stars, with a mass between 10 and 50 percent of the mass of our Sun. This is the most common type of star found in the universe.

You can read the research paper here [pdf]. The image to the right, figure 1 from the paper, shows 71 of those disks, with two-thirds clearly much smaller than our solar system.

Because exoplanet surveys have found many small exoplanets around low-mass stars, this new data suggests that planets can also form from these small accretion disks, and that planet formation is also ubiquitous throughout the universe.

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Astronomers photograph baby stars in Orion

February 20, 2020 9:17 am Robert Zimmerman

Click for full image.

Astronomers using two radio telescopes have created multi-wavelength radio images of 300 protoplanetary disks, or proplyds, found in the star forming region in the constellation Orion. The image to the right shows only a small sampling of the proplyds imaged.

“This survey revealed the average mass and size of these very young protoplanetary disks,” said John Tobin of the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, and leader of the survey team. “We can now compare them to older disks that have been studied intensively with [the radio telescope] ALMA as well.”

What Tobin and his team found, is that very young disks can be similar in size, but are on average much more massive than older disks. “When a star grows, it eats away more and more material from the disk. This means that younger disks have a lot more raw material from which planets could form. Possibly bigger planets already start to form around very young stars.”

Of the disks photographed, four appear to be extremely young, probably less than ten thousand years, because of their very blobby and irregular shape.