How close will asteroid 2012 TC4 come?

Image from 2012, via G. Masi and F. Nocentini/ Virtual Telescope Project.

The Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory in Pasadena, California has said that a small asteroid designated 2012 TC4 will pass very close to Earth on October 12, 2017. These experts said that, even though they can’t yet predict exactly how close it’ll come, they’re certain it’ll fly by at a safe distance. That safe distance could be a very close shave, however, with the space rock passing no closer than 4,200 miles (6,800 km) from our planet. Or it could be a more distant pass, some two-thirds the moon’s distance from Earth. Paul Chodas, CNEOS’ manager, said:

We know the orbit of 2012 TC4 well enough to be certain that it won’t hit Earth.

The calculations on its pass in October, 2017 are based on seven days of tracking 2012 TC4, shortly after it was discovered in 2012. The Pan-STARRS observatory in Hawaii discovered it on October 5, 2012, and, one week later, the asteroid passed Earth at a distance of only 58,905 miles (94,800 km), or about a quarter of the distance between us and the moon. Astronomers haven’t seen the asteroid since 2012, because it’s been so distant and so faint. But the 2012 observations gave them enough information to put Earth in the clear for the 2017 pass. Astronomers also know it’s an elongated and rapidly rotating asteroid. And they know that asteroid 2012 TC4 has made many close approaches to Earth in the past.

As 2012 TC4 starts to approach Earth this summer, large telescopes will be used to re-establish its precise trajectory, CNEOS said.

The new observations are expected to help refine knowledge about its orbit, narrowing the uncertainty about how far it will be from Earth at its closest approach in October.

Brightness measurements made during the week it was observed in 2012 also give an estimated size of 30 to 100 feet (10 to 30 meters). That’s comparable to the meteor that caused a shock wave and explosion in Earth’s atmosphere, over the Russian city of Chelyabinsk, in February 2013, injuring 1,500 people and damaging over 7,000 buildings. The Chelyabinsk meteor, before it struck Earth’s atmosphere, is estimated to have been about 20 meters wide.

Asteroid 2012 TC4 as seen by the Remanzacco Observatory team of Ernesto Guido, Giovanni Sostero, Nick Howes on Oct. 9, 2012. Image via phys.org.

Bottom line: A small asteroid designated 2012 TC4 will pass very close to Earth on October 12, 2017. Even though they can’t yet predict exactly how close it’ll come, experts are certain it won’t hit Earth.

from EarthSky http://ift.tt/2uJVddV

Image from 2012, via G. Masi and F. Nocentini/ Virtual Telescope Project.

The Center for Near Earth Object Studies (CNEOS) at NASA’s Jet Propulsion Laboratory in Pasadena, California has said that a small asteroid designated 2012 TC4 will pass very close to Earth on October 12, 2017. These experts said that, even though they can’t yet predict exactly how close it’ll come, they’re certain it’ll fly by at a safe distance. That safe distance could be a very close shave, however, with the space rock passing no closer than 4,200 miles (6,800 km) from our planet. Or it could be a more distant pass, some two-thirds the moon’s distance from Earth. Paul Chodas, CNEOS’ manager, said:

We know the orbit of 2012 TC4 well enough to be certain that it won’t hit Earth.

The calculations on its pass in October, 2017 are based on seven days of tracking 2012 TC4, shortly after it was discovered in 2012. The Pan-STARRS observatory in Hawaii discovered it on October 5, 2012, and, one week later, the asteroid passed Earth at a distance of only 58,905 miles (94,800 km), or about a quarter of the distance between us and the moon. Astronomers haven’t seen the asteroid since 2012, because it’s been so distant and so faint. But the 2012 observations gave them enough information to put Earth in the clear for the 2017 pass. Astronomers also know it’s an elongated and rapidly rotating asteroid. And they know that asteroid 2012 TC4 has made many close approaches to Earth in the past.

As 2012 TC4 starts to approach Earth this summer, large telescopes will be used to re-establish its precise trajectory, CNEOS said.

The new observations are expected to help refine knowledge about its orbit, narrowing the uncertainty about how far it will be from Earth at its closest approach in October.

Brightness measurements made during the week it was observed in 2012 also give an estimated size of 30 to 100 feet (10 to 30 meters). That’s comparable to the meteor that caused a shock wave and explosion in Earth’s atmosphere, over the Russian city of Chelyabinsk, in February 2013, injuring 1,500 people and damaging over 7,000 buildings. The Chelyabinsk meteor, before it struck Earth’s atmosphere, is estimated to have been about 20 meters wide.

Asteroid 2012 TC4 as seen by the Remanzacco Observatory team of Ernesto Guido, Giovanni Sostero, Nick Howes on Oct. 9, 2012. Image via phys.org.

Bottom line: A small asteroid designated 2012 TC4 will pass very close to Earth on October 12, 2017. Even though they can’t yet predict exactly how close it’ll come, experts are certain it won’t hit Earth.

from EarthSky http://ift.tt/2uJVddV