For the first time, astronomers were able to observe the so-called planetary disk around an exoplanet. Moons are formed in such disks.
Planet formation remains a hot topic in astronomy. It is known that our solar system was formed from a cloud of dust and gas that collapsed under the influence of its gravity. The cloud accelerated around a very young star (the future sun), eventually forming a planet-forming disk 4.5 billion years ago. This is where Earth and the other planets in our solar system originated. But astronomers don’t yet know exactly how planets (and those outside our solar system) formed. Little is known about the composition of the moon.
Fortunately, the latest observations from the Atacama Large Millimeter/submillimeter Array (ALMA) are providing important new insights. Thus, astronomers saw the so-called planetary disk around an exoplanet with high accuracy. In this accumulation of gas and dust Planetemalin
Asteroids have enough mass to form three moons.
The planetary disk is located around the exoplanet PDS 70c. Astronomers had previously discovered the disk, but only now are they able to study it with such high accuracy. Thanks to the new observations, it is known that the diameter of the disk is approximately equal to the distance from the Sun to the Earth – about 150 million kilometers. Moreover, the disk has enough mass to form three satellites the size of our moon, Melt from ESO Partner of ALMA.
Together with 70b, PDS 70c forms a galaxy reminiscent of the duo of Jupiter and Saturn. The two giant exoplanets – discovered a few years ago using the Very Large Telescope – orbit a star about 400 light-years away (it’s only 3,786.912,000,000 km in length).
The special thing about this duo is that both planets are still under construction, says Miriam Kepler, one of the researchers. This allows astronomers to study the processes of planet formation. Also, they are gaining a better understanding of moon formation through this planet disk to observe PDS 70c more closely.
Plane in crafting
While the size and mass of this disk have been determined, the international research team found that the exoplanet PDS 70b shows no visible traces of the disk surrounding the planet. Scientists suspect that all the dust in its environment is made up of the neighboring planet PDS 70c.
“This is a very exciting result, and something we’ve been looking for for a long time,” said Michael Hogerheide of the Leiden Observatory when asked. PDS 70 is one of the very few systems with exoplanets at Planet shaped disk. Thousands of exoplanets have already been discovered, but they are much older. In PDS 70 we see the exoplanets right after their formation, and that we now see the disk around the planet Self Being able to see is very important.”
According to the astronomer, who was not involved in the study, the work shows how powerful the ALMA telescope can be at finding these types of disks. “One of the questions we are trying to solve is to what extent the planets continue to increase in mass due to the flow of material from this disk into the planet, and what kind of systems are used to form the moons of exoplanets. So far, only a few exoplanets have been found, and PDS 70 It’s the only one where we can directly detect exoplanets. Hopefully we can find similar planetary disks, and more young exoplanets, in those other systems as well.”
Bild: ALMA (ESO/NAOJ/NRAO) / Benisty et al.