Patterns detected on asteroid particles collected in a nearly doomed Japanese space mission support the theory that the celestial body endured intense heat, solar winds and a collision, according to researchers. The researchers at the Japan Aerospace Exploration Agency (JAXA) said June 22 that studies of such patterns could lead to a new method of determining how such space objects were formed.
The particles were collected after Japan’s Hayabusa space explorer landed on the Itokawa asteroid in 2005. Despite several equipment failures and malfunctions, the Hayabusa managed to collect particles only a few tens of micrometers in size from the surface of the asteroid.
The explorer burned up when it re-entered the Earth’s atmosphere in 2010, but it brought back a capsule containing the world’s first samples directly collected from an asteroid.
The JAXA researchers used electron microscopes and other equipment to analyze the surface of the particles and found four different patterns.
One pattern, formed 4.5 billion years ago, indicated crystallization after exposure to intense heat when Itokawa was part of a larger asteroid.
Another pattern is believed to have been formed from the impact of a collision with a meteorite no earlier than 1.3 billion years ago. The study also found evidence of weathering due to exposure to the solar wind between 1 million and 1,000 years ago.
In addition, the researchers said they found signs that the particles had rubbed against each other.
JAXA has launched the Hayabusa 2, a revised model, to another asteroid named Ryugu. The Hayabusa 2 is scheduled to return to Earth in 2020.
Hisayoshi Yurimoto, a specially appointed professor at JAXA’s Institute of Space and Astronautical Science, said the finding of such patterns could improve asteroid studies.
“(The method) can perform analyses without damaging the invaluable particle samples,” Yurimoto said. “We will be able to contribute to the analysis of samples that the Hayabusa 2 will bring back.”