We are currently living under very volatile skies. Less than one year after a 10,000 ton meteorite exploded above the Russian city of Chelyabinsk in the Urals injuring 950 people, Russian scientists reveal that a nearby area of the country narrowly missed an impact from a 15 meter asteroid which skimmed past Earth last weekend. The asteroid, which was moving at 16km per second, passed within 11,300km of the Earth’s surface, an altitude which is below the orbit of geostationary satellites. It was discovered during its near miss by the Master Tunka station near Lake Baikal. The asteroid was not previously known.
Besides ending life on planets through impacts, asteroidsmay also spread life throughout the universe. Although thislife is in the form of tiny bacteria which are only thebeginning of a long evolution to intelligent life, it doesmean that most life will be carbon-based, so if we ever domeet aliens we may recognize them. The planet(s) where lifeoriginated may have died long ago, but thanks to spacerocks, life still exists.
Maggie McKee writes in New Scientist that the nearby starsystem Tau Ceti, which astronomers think could have life onit, has 10 times more asteroids and comets than are in ourSolar System. They could have seeded life on these planetsbut they probably killed it off as well.
It’s been discovered that the force of sunlight on an asteroid can change its orbit, which is one reason why asteroids change direction and head for Earth. What we don’t know is this: Will the increased solar activity on the sun right now have an increased effect on asteroids?
Eugenie Samuel Reich writes in New Scientist that astronomers have detected the influence of sunlight on asteroids for the first time, since it’s very subtle. However, it’s enough to coax them out of the Solar System’s asteroid belt and into an orbit that can impact Earth.
It’s not just the big asteroids we have to watch out for?the little rocks can be dangerous too. They’re hundreds of them out there and they’re hard to spot, but NASA has decided it had better start searching for them.
Robert Roy Britt writes in Space.com that it will cost at least $236 million to add a search for small asteroids to their ongoing Near Earth Object (NEO) detection program. An asteroid twice the size of a football field or bigger hits the Earth about every 15,000 to 20,000 years, according to NASA’s Donald Yeomans. Impacts from smaller space rocks cause only regional problems, but these could be severe, and there are so many more of them that this kind of impact is much more likely to occur.