Hunting asteroids - May 06, 2008
Canada is set to launch the first dedicated space satellite to watch for near-Earth objects (Vancouver Sun). The question is: do we really need one?
A number of Earth-bound telescopes are already used to spot and track near-Earth objects (NEO), including under the auspices of Nasa’s NEO Project. Commentators in New Scientist argue that the space-based telescope (called NEOSSat) will have better luck spotting asteroids that are within Earth orbit: these also tend to stay in line with the Sun, meaning they are only visible in the sky close to sunset or sunrise, when background light tends to drown them out. But they are also more likely to hit us, the article says.
But ground-based satellites can spot these too, even if it is a little harder. Alan Harris of the Space Science Institute in Boulder Colorado, US, told New Scientist he doesn’t think the project will add too much to what’s already available.
But hey, it’s only costing $10 million. And statistically Canada (the second largest country after Russia) has a lot of area sitting waiting to be struck by an asteroid, so maybe that makes them keen to get in on the game… even if there aren’t that many people actually living in most of it.
Comments
Athabasca, Alberta, Canada tar sands hold 230 billion tonnes of hydrocarbon total. Black Mesa, northern Arizona, United States holds 21 billion tonnes of coal. Immense methane hydrate deposits ring continental shelves - 7.4 trillion SCM of net methane surround Japan. Western Oklahoma holds 250+ million tonnes of gypsum. A small asteroid impact would be chemically devastating worldwide - combustion or sulfuric acid release.
Posted by: Uncle Al | May 6, 2008 05:43 PM
The smaller ones have profound strategic value. It costs practically no energy to export metal mined from one, and very little energy to get to it from LEO.
The smallest may have a different strategic value: they may be nudged into an orbit that intersects Earth's with an undetectably small energy input, for perfect deniability. It would take a long time to strike, but doesn't (e.g.) China expect Taipei to be a problem for a long time to come?
There are plenty of reasons to want to know the resting orbits of all the little rocks nearby.
Posted by: Nathan Myers | May 6, 2008 10:52 PM
It certainly merits serious consideration.
By example, asteroid 2002 MN was very close and came from sunward to be discovered after it passed earth.
Posted by: Mang | May 7, 2008 09:52 PM
The only reason Alan Harris claims it won't help the efforts is because he's an American and this is not an American project. If this were an American satilite, as opposed to a Canadian one, he'd be all over it saying it was the greatest advancement in Earth protection since the invention of the telescope (also not American).
Posted by: david | May 8, 2008 11:56 PM