Skip to main content

Astronomers say that the water found in the "Christmas Comet" is very similar to the water in the Earth.

Where does the water on the planet come from? This problem has been plaguing scientists for many years. An international team of astronomers tried to answer this question by studying the water found in the comet 46P / Wirtanen.
 Astronomers say that the water found in the "Christmas Comet" is very similar to the water in the Earth.

We have identified a huge reservoir on the periphery of the solar system, where the water is very similar to the water on Earth. "The first author of the study, Darek Lis, said in a statement.The study was published in the journal Astronomy and Astrophysics on May 20, and astronomers used NASA's Stratospheric Infrared Astronomical Observatory (SOFIA) to study the so-called "Christmas Comet" in 2018. Flying in the earth in December. The SOFIA Air Observatory was converted from a Boeing 747.A long-standing theory holds that the earth's water is from ice comets outside the solar system. The theory holds that when a comet collides with the early Earth, the impact brings water into the Earth's environment. To determine if the water in this comet is similar to the water on Earth, astronomers used SOFIA to observe 46P / Wirtanen and analyzed the ratio between the two different types of water.

The water molecules we know are composed of two hydrogen atoms and one oxygen atom. This form of water molecules constitutes most of the water found on Earth. There are only three isotopes of hydrogen: (P) has one proton in the nucleus, no neutron; (D) has one proton and one neutron in the nucleus; (T) has one proton in the nucleus, 2 Neutron. But an unusual water, heavy water, is a compound of strontium and oxygen. The two hydrogen isotopes in the heavy water molecule are one more neutron than the normal hydrogen atom. Studying the ratio of strontium to hydrogen (D / H ratio) can provide astronomers with more information about the origin of water.

The D/H ratio of comets is usually one to three times higher than the ratio of the Earth's oceans, but astronomers have found that the ratio of 46P / Wirtanen is basically the same as what we see on Earth.The previous two comets, 103P/Hartley 2 and 45P/H-M-P, showed similar proportions. It is worth noting that all three are classified as “extremely active comets”, which release water on the surface and in the atmosphere as they approach the temperature of the sun. The team found that the D/H ratios in these three were related to the water present in the atmosphere. As a result, they believe that all comets may contain earth-like water locked in rock.This discovery has once again opened the debate about the earth's water source. Other comets originated from the Oort cloud at the edge of the solar system and did not exhibit similar D/H ratios.