Close asteroid fly-by will help test planetary defence capabilities

Nasa is using this opportunity to test it's "planetary defence system" put in place to protect Earth from a doomsday asteroid threat.

The Asteroid didn't Earth this time, but it should serve as a wake-up call, that we need to do more to detect incoming asteroids.

The asteroid, dubbed 2012 TC4, measures between 30 and 100 feet across - potentially making it larger than the 65-foot space rock that blew up over Chelyabinsk, Russia, in February 2013.

It is expected to fly past Earth on October 12, and while NASA said it is "absolutely certain" the rock will miss the planet, they are unsure how close it will pass.

The space agency says its Double Asteroid Redirection Test (DART) spacecraft will be ready for full tests on another asteroid flyby in 2022.

"This is the flawless target for such an exercise because while we know the orbit of 2012 TC4 well enough to be absolutely certain it will not impact Earth, we haven't established its exact path just yet", said Paul Chodas, manager of NASA's Center for Near-Earth Object Studies (CNEOS). Traditionally, however, these exercises involved hypothetical impactors, prompting Vishnu Reddy of the University of Arizona's Lunar and Planetary Laboratory, to propose a slightly more realistic scenario, one that revolves around an actual close approach of a near-Earth asteroid, or NEA.

For NASA scientists like Michael Kelley, it is important for them to know when a space rock will make a close approach to everyone's safety.

"This is the flawless target for such an exercise because while we know the orbit of 2012 TC4 well enough to be absolutely certain it will not impact Earth, we haven't established its exact path just yet", said Paul Chodas, manager of the Center for Near-Earth Object Studies (CNEOS) at JPL.

The asteroid last whipped by Earth in 2012 at about one-fourth the distance to the moon.

Details on what this system actually entails are unclear, but it will test "precise orbit determination" and "international communications", according to NASA.

"Being able to observe small asteroids like this one is like looking at samples in space before they hit the atmosphere and make it to the ground", Reddy had said when TC25 was observed past year. "It will be incumbent upon the observatories to get a fix on the asteroid as it approaches, and work together to obtain follow-up observations than make more refined asteroid orbit determinations possible".

NASA is using the event to put to the test its "doomsday" asteroid tracking system to determine its exact trajectory using ground-based telescopes.