ilan
09-09-2018, 12:13 PM
Asteroid Itokawa gives up its secrets
Paul Scott Anderson in SPACE | September 8, 2018
Itokawa is the 1st asteroid from which samples were obtained and returned to Earth. From these samples, scientists have figured out Itokawa’s true age and geologic history.
http://en.es-static.us/upl/2018/09/Itokawa8_hayabusa_960.jpg
Itokawa, as seen by the Japanese spacecraft Hayabusa in 2005. The asteroid is basically a “rubble pile” of material held together by gravity. Image via JAXA/ISAS.
Back in 2005, the first asteroid sample-return mission – Japan’s Hayabusa spacecraft – reached its target, the asteroid Itokawa. In 2010, Hayabusa (Japanese for “peregrine falcon”) arrived back at Earth with its precious cargo of dust samples from the asteroid. In the years since, scientists have been busy studying those samples, to better understand the origin and geologic history of Itokawa. Now, a new peer-reviewed study, published in the journal Scientific Reports on August 7, 2018, details new findings about Itokawa’s age and origin for the first time.
The asteroid – basically a “rubble pile” held together by gravity – is 4.6 billion years old, about the same age as the solar system itself. But it didn’t always look the way it does now; the scientists determined that the “original” Itokawa had collided with another asteroid around 1.5 billion years ago, and was almost destroyed. The resulting debris, however, re-assembled back into the “rubble pile” we see today. Also, it seems that Itokawa inhabited the main asteroid belt up until only the past couple hundred thousand years or so. It now resides in a different orbit as a Near Earth Asteroid (NEA) or Earth-crossing asteroid, which may result in a collision with Earth within the next million years or so, according to scientists. That possibility is based on a previous study which simulated 39 nearly identical orbits of the asteroid. It’s also possible that Itokawa will break apart within that time.
Paul Scott Anderson in SPACE | September 8, 2018
Itokawa is the 1st asteroid from which samples were obtained and returned to Earth. From these samples, scientists have figured out Itokawa’s true age and geologic history.
http://en.es-static.us/upl/2018/09/Itokawa8_hayabusa_960.jpg
Itokawa, as seen by the Japanese spacecraft Hayabusa in 2005. The asteroid is basically a “rubble pile” of material held together by gravity. Image via JAXA/ISAS.
Back in 2005, the first asteroid sample-return mission – Japan’s Hayabusa spacecraft – reached its target, the asteroid Itokawa. In 2010, Hayabusa (Japanese for “peregrine falcon”) arrived back at Earth with its precious cargo of dust samples from the asteroid. In the years since, scientists have been busy studying those samples, to better understand the origin and geologic history of Itokawa. Now, a new peer-reviewed study, published in the journal Scientific Reports on August 7, 2018, details new findings about Itokawa’s age and origin for the first time.
The asteroid – basically a “rubble pile” held together by gravity – is 4.6 billion years old, about the same age as the solar system itself. But it didn’t always look the way it does now; the scientists determined that the “original” Itokawa had collided with another asteroid around 1.5 billion years ago, and was almost destroyed. The resulting debris, however, re-assembled back into the “rubble pile” we see today. Also, it seems that Itokawa inhabited the main asteroid belt up until only the past couple hundred thousand years or so. It now resides in a different orbit as a Near Earth Asteroid (NEA) or Earth-crossing asteroid, which may result in a collision with Earth within the next million years or so, according to scientists. That possibility is based on a previous study which simulated 39 nearly identical orbits of the asteroid. It’s also possible that Itokawa will break apart within that time.
