TOKYO (AP) – Japanese astronauts on Thursday said they would examine soil samples brought back from a distant asteroid in an attempt to find the source of heat that altered the celestial body in their search for clues as to the origin of the solar system and life. on earth.
Scientists from the Japan Aerospace Exploration Agency said they had conducted a preliminary study of 5.4 grams (0.19 ounces) of soil, far more than the minimum 0.1 gram sample they had hoped for, which the spacecraft Hayabusa2 in December of the asteroid Ryugu brought back. more than 300 million kilometers (190 million miles) from Earth.
About 3 grams of the black grains come from Ryugu’s surface and were collected when Hayabusa2 touched the asteroid in April 2019. About 2 grams larger fragments, up to about 1 centimeter (0.4 inches), were obtained from below the surface in a crater made by Hayabusa2 when it landed a second time three months later.
JAXA scientists found that the asteroid was exposed to extremely high temperatures on its surface and underground, possibly by an internal heat source or planetary collisions instead of heat from the sun, based on the infrared spectrophotometer analysis of data transmitted by Hayabusa2 .
Kohei Kitazato, a planetary scientist from the University of Aizu who works with JAXA, said his team found indications of heat of more than 300 degrees Celsius (572 degrees Fahrenheit), both on the asteroid and underground.
He said the ground underground would not reach the temperature of the solar heat alone, suggesting that radiant internal heat or planetary collisions affected Ryugu when it was still part of a parent body billions of years ago, causing evaporation of its water. has.
His earlier study, conducted with scholars from Brown University and more than thirty other institutions, was published last month in the journal Nature Astronomy.
JAXA continues with the initial investigation of the asteroid samples before full studies next year. Scientists will also investigate possible traces of organic matter in the hope that it will provide insights into the origin of the solar system and life on earth.
After studies in Japan, some samples will be shared with NASA and other international space agencies for further research.
Hayabusa2 continues an 11-year expedition to another small and distant asteroid, 1998KY26, to study possible defenses against meteorites that could fly to Earth, while conducting various tests that could be used in future Japanese space missions, including the planned 2024 MMX monster return mission from one of the Martians.