Asteroid "Ryugu" Maybe it was in an orbit passing inside Mercury 5:01 on May 8
The asteroid "Ryugu" surveyed by the Japanese spacecraft "Hayabusa 2" was found to have been orbiting inside Mercury, which is closer to the Sun, according to the Japan Aerospace Exploration Agency. Did.
"Ryugu" is an asteroid that is orbiting the sun mainly between Earth and Mars, and "Hayabusa 2" has been photographed and analyzed in detail by the onboard camera.
As a result, it was found that most of the sand and rocks on the surface were heated to a high temperature of 600 degrees or more that could not be expected at the current distance from the sun and turned red.
On the other hand, the new crater has confirmed that blue-colored sand and rocks have not been heated because it is not at a high temperature, and it is thought that the distance from the sun has been relatively far away.
For this reason, "Ryugu" is the innermost planet in the solar system, with the distance to the sun being about one-third to one-fifth of the current period for a period of approximately 8 million years to 300,000 years ago. It turned out to be an orbit that passes further inside than Mercury, and it was later discovered that it may have changed to the current orbit.
The reason for the change in the orbit is thought to be the influence of the gravitational force of the celestial body, but I do not know in detail.
Associate Professor Tomokatsu Morota of the University of Tokyo, who conducted the analysis, said, "I think that I was able to verify the geological change of the asteroid's orbit for the first time. I am looking forward to the analysis of the sand brought back by Hayabusa2." I am.