Earth_Eastern_HemisphereWhile many people will be busy getting their costumes together to go trick-or-treating or partying tomorrow, astronomers at observatories around the world, including NASA’s Deep Space Network in Goldstone, CA, will be busy studying an asteroid called TB145 which will pass within 490,000 km of Earth on Saturday.

While hundreds of near-Earth objects have been discovered and their orbits plotted to determine if they might one day pose a threat to Earth, TB145 wasn’t detected until Oct. 10. Egg-shaped, roughly 400 km in diameter, and travelling at 35 km a second, the “Great Pumpkin” as astronomers have dubbed it, would’ve exacted an unimaginable toll on Earth had it been on a collision course.

Fortunately, while the asteroid will pass near us (slightly further than the distance of the Moon, actually) we won’t have to cope with any armageddon scenario — at least, not tomorrow. As for what the future might hold, who’s to say? Over its roughly 4.5 billion year existence, Earth has been impacted countless times by rogue asteroids and comets from space.

Many early impacts were beneficial, delivering water, minerals, and possibly even life, to the planet. But later impacts, most notably at the end of the Cretaceous period 66 million years ago which triggered the extinction of the dinosaurs, caused widespread devastation, and the consequences now would be equally dire.

Efforts are underway, such as the Spacewatch program at the University of Arizona, to search for unknown near-Earth objects and track their orbits into the future to determine if they might one day threaten Earth. If you check out this CBC report, you’ll also learn that scientists and engineers are brainstorming different strategies for one day being able to intercept and alter the path of potential planet-killers so they don’t strike Earth.

We’re still decades away from being able to do anything like that. But the more data we can collect on asteroids and comets, the better able we’ll be to develop technologies to counter the threat they pose to our survival.