Large amounts of water around the stars

Under the supervision of the University of Leiden in the Netherlands, 50 astronomers have pooled the knowledge that exists about water in interstellar space.

It was previously difficult to detect, but based on observations made with the Herschel Space Telescope, some new information has been obtained about the origin of water in planetary systems.

Chalmers researchers participated in the project.

We looked at everything from small systems to ancient systems – and from low mass to high mass, to trace the path of water from collapsing clouds to the disks of planets. The study, now published in the Journal of Astronomy and Astrophysics, is a compilation of everything we’ve done since 2009, says Chalmers researcher Per Bjerkeli in the Department of Space Sciences, Geology and Environment, to Ny Teknik.

Water mainly forms in the form of ice, which accumulates on the particles in the cold faint clouds of dust and dust. When parts of interstellar clouds collapse into stars, it becomes clear that water molecules can stick to their particles without melting or breaking. They will form part of the rotating disk that forms around the star, and the materials that would form the base for the system’s planets.

It is very difficult to measure how many liters of water are in each region of planetary formation, but you can make qualified guesses based on the data you have. This is more than enough to fill the oceans, he says.

An important puzzle piece

This is despite the fact that it was observed that more water left the systems than was left in the disks, which surprised the researchers. When the systems are young, Bear says, they send massive outflows – they’re like airplanes and can reach speeds of 400-500 kilometers per second. The subproject was specifically to study these outflows. Chalmers also contributed certain parts of the HIFI instrument on the Herschel Telescope, an important piece of the puzzle for the new discoveries.

The other two receivers have taken pictures while HIFI is just a spectrophotometer. Since you have this spectral resolution, you can also get information about the velocity. If you have something moving from us or towards us, that frequency gets pushed a little bit, and it made it possible to measure the velocity of the water and distinguish what falls from what is being sprayed, ”he says.

According to Birr, it is difficult to define what new discoveries could mean for the possibility of life on exoplanets. The discovery of an abundant amount of water in disks around young stars did not puncture the idea that Earth is The water could be the result of bombing comets. The project looked at water-rich comets.

If we take a glass of water to drink, then one in ten thousand molecules is called heavy water, but when you look at comets, this ratio was not the same. Therefore, it is thought that the water may not come from there, because there is no reason to change this relationship. by the time. But in some comet types, it appears to be in reality in roughly the same proportion, so the theory that the water came from a comet bombardment has gained some life again. But it is not clear yet, there are other research groups that believe that the water ended directly on Earth when the planet formed, says Bear Bjerkley.