Asteroid impact prediction

2008 TC3 was the first asteroid we saw before it hit Earth. This picture shows the direction it came from in red. It shows the guess of where is exploded in orange. The green line shows the direction the explosion sound was heard from by the atomic bomb microphones.

Asteroid impact prediction warns about asteroids hitting Earth, and when and where they will hit the Earth. Most asteroids will not hit Earth. Asteroid impact prediction works by finding the ones that will hit Earth. It finds asteroids that might hit Earth in the future. This works well for big asteroids as they can be seen easily from a long distance, many years before they come close to Earth.

There aren't many big asteroids, but there are millions of smaller space rocks. They are not normally bright enough to see until they are close to Earth. We use telescopes to find the asteroids that are going to hit Earth soon. The telescopes are not good enough to see the small asteroids unless everything is perfect. Because of this we almost never see them before they hit Earth.^[1]

↑ "Update to Determine the Feasibility of Enhancing the Search and Characterization of NEOs" (PDF). Near-Earth Object Science Definition Team Report 2017. NASA. Retrieved 7 July 2018.

[JPL-2017-SDT-Update-1] "Update to Determine the Feasibility of Enhancing the Search and Characterization of NEOs" (PDF). Near-Earth Object Science Definition Team Report 2017. NASA. Retrieved 7 July 2018.

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