Asteroid 2002 NT7
Written by Jerry Coffey
Asteroid 2002 NT7 is 2.6 km in diameter and was thought to be a significant impact threat in 2019. After more astronomers brought their instruments to bear and an accurate trajectory was plotted the threat level was reduced to a 0 on the Torino and Palermo scales. The same asteroid will return in 2060 and could be a possible threat then, but given enough time to plot future orbits and trajectories, NASA will probably rule out the threat before the asteroid can return.
Asteroid 2002 NT7 was discovered by the LINEAR team on July 9, 2002. The asteroid orbit is highly inclined when compared to the Earth's orbit around the Sun. It nearly intersects the orbit of the Earth. While the orbits of Earth and asteroid 2002 NT7 are close to one another at one point in their respective orbits, that does not mean that the asteroid and Earth themselves will get close to each other. After an object like NT7 is discovered the limited number of observations make it difficult to figure a trajectory and it is given a score of 1 on the Torino scale. A 1 only means that the object requires further study. More observations will be made and an accurate trajectory will be made then the Torino score will be lowered to0 as the object is determined to be of no threat to the Earth.
Asteroid 2002 NT7 still tops the list of NASA/JPL NEO Impact Risks because of the low-probability Earth impact prediction for 2019. But Steve Chesley and other asteroid experts assure that the sky is not falling, and the rock will, in all probability, at this stage, orbit safely on by come 2019. "While this prediction is of scientific interest, the probability of impact is just not large enough to warrant public concern," reassures Chesley. "It is unusual, but it's not anything that would deserve as much attention as it's gotten." In fact, Chesley adds: "We've seen much higher probabilities, but since this asteroid is quite large, its moderately high probability combined with its great size raises it to a higher level on our risk scales. In other words, this one went over the threshold on one of the risk scales we use, someone noticed and said, 'Hey that's never happened before.' There's your story."
Asteroid 2002 NT7 has a very low impact probability, but had quite a bit of hype. It just goes to show you what can happen when scientific facts are misconstrued by the media and then sensationalized. That fact is that there is no chance for an impact in 2019 and probably none in 2060.
There is a good article here on Universe Today and NASA has a very interesting page on the the asteroid 2002 NT7. Astronomy Cast has a good episode on asteroid collisions.
Filed under: Astronomy
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- Asteroid Narrowly Misses the Earth
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