Itokawa Asteroid
Although their size is small—less than the thickness of a human hair—the three dust particles have a history stretching back billions of years, stretching back to an asteroid and storing many of its secrets.
Three particles from the Itokawa asteroid have revealed that this type of space object is much older and much more massive than previously thought.
According to a study published Monday in the journal “Proceedings” of the US National Academy of Sciences, it includes a review of existing plans to avoid a collision with the planet.
Three samples were brought back in 2005 from an asteroid 300 million kilometres from Earth. The Japanese space probe “Hayabusa” transported these samples to Earth along with hundreds of other particles from Itokawa. After five years,
Professor Fred Jordan of the Faculty of Earth and Planetary Sciences at Australia’s Curtin University tried to determine the age of Itokawa, a type of asteroid described as having “loose mass.”
It was formed by the merging of fragments of a compact asteroid.
Compact asteroids are known to have lifetimes of a few hundred million years and are gradually eroded by collisions with other asteroids.
Loose-mass asteroids like Itokawa have a very heterogeneous composition, including a variety of rocks, dust, pebbles, and voids that hold together with little effect of gravity.
Professor Jordan compared it to “a giant pillow in space, and pillows can absorb shocks.”
To determine to what extent, the team analysed the crystal structure of the samples, looking for and dating distortions from the collision that created Itokawa.
The researchers concluded that Itokawa formed after a collision that occurred at least 4.2 billion years ago, which is about the age of the Earth (4.5 billion years), but more importantly, it is ten times older than the age of homogeneous asteroids of the same size.
Because of the significance of this asteroid’s age, Jordan believed that some of his colleagues would not believe him.
The study suggests that the comfort of this type of space object upon collision may be much greater than previously thought.
The geochemist said that this is the result of adopting protective measures against the Earth’s collision with this type of asteroid.
Scientists have said that the “DART” experiment, which was successfully conducted by the American Space Research Organization (NASA) last year to repel an asteroid, is possible with an object like Itokawa. But this would require much more energy, such as with a nuclear warhead, so that “the shock wave could deflect the asteroid from its trajectory.”
