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Canada will join NASA as part of a mission to bring back rocks from an asteroid that is considered a potential threat to hit the Earth some day.
Known as a “sample return” mission, the unmanned spacecraft would launch in late 2016, if all goes well, as it heads to the asteroid Bennu.
NASA says the overall mission will cost $800 million, excluding the launch vehicle. That makes it pricier than a typical mission to Mars.
Canada’s $61-million contribution: MacDonald, Dettwiler and Associates Ltd. (MDA), together with its industrial partner, Optech, will make an altimeter. It’s similar to the lidar (like a radar, but using laser light) that Canada put on the Mars Phoenix lander several years ago. That highly successful instrument was the first to detect snow falling on Mars, and may have paved the way for the new role in the asteroid mission.
The instrument will scan the entire surface of Bennu, and create a detailed, three-dimensional image of it. That would let the mission controllers choose a place for contact.
The spacecraft would not quite land. Instead, the plan is to hover near the surface and reach out with a mechanical scoop to lift about 60 grams of rocky material off the surface. That’s less than three ounces.
Canada’s contribution means we will get four per cent of whatever rocks are returned to Earth.
The sample will be returned to Earth in 2023.
Bennu is a tiny target compared to Mars or the moon: just 493 metres across. But has been seen as having the potential to hit Earth some day.
Attention to asteroids has grown in recent years, partly because their light gravity makes it easy to leave them for a return to Earth. They are considered potential sources of valuable minerals, and scientists are also interested in learning to nudge one into a different path if it threatens Earth.
The lead Canadian science on the project will be Alan Hildebrand of the University of Calgary. Also prominent is Michael Daly of York University.
There has only ever been one “sample return” from an asteroid. The Japanese Hayabusa mission was intended to land on an asteroid and collect samples, but it succeeded only in touching the asteroid briefly and collecting tiny amounts of grains. It returned to Earth in 2010.
The new mission is called OSIRIS-Rex. It is scheduled to reach the asteroid in late 2018 and spend months maneuvering near it before attempting the contact.
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
Known as a “sample return” mission, the unmanned spacecraft would launch in late 2016, if all goes well, as it heads to the asteroid Bennu.
NASA says the overall mission will cost $800 million, excluding the launch vehicle. That makes it pricier than a typical mission to Mars.
Canada’s $61-million contribution: MacDonald, Dettwiler and Associates Ltd. (MDA), together with its industrial partner, Optech, will make an altimeter. It’s similar to the lidar (like a radar, but using laser light) that Canada put on the Mars Phoenix lander several years ago. That highly successful instrument was the first to detect snow falling on Mars, and may have paved the way for the new role in the asteroid mission.
The instrument will scan the entire surface of Bennu, and create a detailed, three-dimensional image of it. That would let the mission controllers choose a place for contact.
The spacecraft would not quite land. Instead, the plan is to hover near the surface and reach out with a mechanical scoop to lift about 60 grams of rocky material off the surface. That’s less than three ounces.
Canada’s contribution means we will get four per cent of whatever rocks are returned to Earth.
The sample will be returned to Earth in 2023.
Bennu is a tiny target compared to Mars or the moon: just 493 metres across. But has been seen as having the potential to hit Earth some day.
Attention to asteroids has grown in recent years, partly because their light gravity makes it easy to leave them for a return to Earth. They are considered potential sources of valuable minerals, and scientists are also interested in learning to nudge one into a different path if it threatens Earth.
The lead Canadian science on the project will be Alan Hildebrand of the University of Calgary. Also prominent is Michael Daly of York University.
There has only ever been one “sample return” from an asteroid. The Japanese Hayabusa mission was intended to land on an asteroid and collect samples, but it succeeded only in touching the asteroid briefly and collecting tiny amounts of grains. It returned to Earth in 2010.
The new mission is called OSIRIS-Rex. It is scheduled to reach the asteroid in late 2018 and spend months maneuvering near it before attempting the contact.
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
