In an article published in the journal Nature Astronomy on August 15, scientists from Japan suggest that water and organic materials might have been brought to our planet from the outer edges of the solar system.
Key highlights
- The scientists made the hypothesis after analysing samples from the asteroid Ryugu, collected by the Japan Aerospace Exploration Agency’s (JAXA) Hayabusa-2 probe, which had brought 5.4 grams of rocks and dust from the asteroid to Earth in December 2020.
- The Hayabusa-2 mission was launched in December 2014 when the spacecraft was sent on a six-year voyage to study the asteroid Ryugu.
- The spacecraft, which was approximately the size of a refrigerator, traveled more than 5 billion kilometers during its journey.
- The spacecraft arrived at the asteroid in mid-2018 after which it deployed two rovers and a small lander onto the surface.
- In 2019, the spacecraft fired an impactor into the asteroid’s surface to create an artificial crater with a diametre of a little more than 10 metres, which allowed it to collect the samples.
- In December 2020, Hayabusa-2 delivered a small capsule that contained the rock and dust samples when it was 220,000 km from the Earth’s atmosphere, which safely landed in the South Australian outback.
- Hayabasu2’s predecessor, the Hayabusa mission, brought back samples from the asteroid Itokawa in 2010.
About Asteroids
- Asteroids are rocky objects that orbit the Sun, much smaller than planets. They are also called minor planets.
- According to NASA, there are 994,383 known asteroids, the remnants from the formation of the solar system over 4.6 billion years ago. Asteroids are divided into three classes.
- First are those found in the main asteroid belt between Mars and Jupiter, which is estimated to contain somewhere between 1.1-1.9 million asteroids.
- The second group is that of trojans, which are asteroids that share an orbit with a larger planet. NASA reports the presence of Jupiter, Neptune and Mars trojans. In 2011, they reported an Earth trojan as well.
- The third classification is Near-Earth Asteroids (NEA), which have orbits that pass close to the Earth. Those that cross the Earth’s orbit are called Earth-crossers. More than 10,000 such asteroids are known, out of which over 1,400 are classified as potentially hazardous asteroids (PHAs).
(Source: Indian Express)
