New telescope to scan the sky of asteroids colliding with the Earth

ASTEROID DETECTOR. A photograph and a mixture of basic design rendering showing a view of the exterior building completed from the road leading to the site. Photo of LSST / NSF / AURA project, Creative Commons BY-NC-SA 4.0

By sunrise on February 15, 2013, an extremely bright and other-worldly object was seen crossing the Russian skies before to explode at about 97,000 feet The surface of the earth. The ensuing explosion damaged thousands of buildings and injured around 1,500 people in and around the Russian city of Chelyabinsk. Although it sounds like the first scene of a sci-fi movie, this invader was not an alien spaceship attacking humanity, but a 20-meter-wide asteroid that had crashed into the Earth . [19659006Cequidianwhichwasthatpeoplewasthatthetastanoof20metersexistedbeforeenteringtheatmosphericrestrecematin

As an astronomer, I study objects in the sky that change brightness on short periods. – observations that I use to detect planets around other stars. Much of my research is to understand how we can better design and operate telescopes to monitor an ever-changing sky. This is important because the same telescopes that I use to explore other star systems are also designed to help my colleagues discover objects in our own solar system, such as asteroids colliding with the Earth.

Near Earth Objects ]

A meteor is a piece of matter that enters the Earth's atmosphere. Before Chelyabinsk's meteor knew of his disappearance on Earth, he was in orbit around our sun like an asteroid. These rocky objects are normally considered limited to the asteroid belt between Mars and Jupiter. However, there are a lot of asteroids throughout the solar system. Some, like Chelyabinsk's meteor, are known as Near Earth Objects (NEO).

The Chelyabinsk meteor probably comes from a group of near – Earth objects called Apollo asteroids, named after the 1862 Apollo asteroid. There are more than 1600 known Apollo asteroids recorded in the JPL small body database that have orbits that can cross the path of the Earth and are large enough (over 140 diameter meters) dangerous asteroids (PHAs) because a collision with the Earth would devastate the affected area.

The scars of these past collisions are prominent on the moon, but the Earth also bears the marks of such impacts. The Chicxulub Crater on the Yucatan Peninsula in Mexico was created by the Chicxulub asteroid that drove the dinosaurs to extinction. The crater of Barringer, Arizona, is only 50,000 years old . The question is not whether a dangerously large asteroid will collide with the Earth, but when?

Threat Search

The US Government takes seriously the threat of a collision of asteroids. In section 321 of the NASA Authorization Act of 2005 the Congress asked NASA to develop an NEO search program. NASA has been tasked with identifying 90% of all near-Earth objects over 140 meters in diameter. Currently, they estimate that three quarters of the 25,000 PLWHA have not yet been found

To achieve this goal, an international team of hundreds of scientists, including myself , complete the construction of the Large Scale Synchronous Telescope (LSST) in Chile, which will be an essential tool to alert us to PLHIV.

LSST. Exterior view of the Large Synoptic Survey Telescope, which is still under construction. Sublease Cerro Pachón, Chile. Photo of LSST / NSF / AURA Project, Creative Commons BY-NC-SA 4.0

With significant funding from the US National Science Foundation, LSST will be looking for PLHIV during its 10-year mission by observing the same area every hour. intervals searching for objects having changed position.

Everything that moves in an hour must be so close that it is in our solar system. Teams led by researchers from University of Washington and JPL both produced simulations showing that LSST alone would be able to find about 65% of PLHIV. If we combine the LSST data with other astronomical surveys such as Pan-STARRS and Catalina Sky Survey we believe we can help achieve this goal by discovering 90% of potentially dangerous asteroids . [19659020] Prepare to Avoid Disaster

The Earth and these asteroids are in orbit around the sun, just on different paths. The more the observation of a given asteroid is important, the more its orbit can be mapped and predicted accurately. The biggest priority, then, is to find asteroids that could collide with Earth in the future.

PHA. A potentially dangerous asteroid is over 140 meters in diameter and can devastate the area where it lands. Shutterstock photo

If an asteroid is on a collision course for hours or days before it happens, the Earth does not have many options. It's as if a car is suddenly withdrawing in front of you. There is little you can do. If, however, we find these asteroids years or decades before a potential collision, then we might be able to use the spacecraft to push the asteroid enough to change its path so that it and Earth do not collide

This is, however, easier said than done, and currently, no one really knows how an asteroid can be redirected. There have been several proposals from missions by NASA and European Space Agency to do so but until now, they have not gone through the early stages of the development of the mission

The B612 Foundation a private non-profit group, also trying to raise funds privately for a mission of reorientation of an asteroid, and they could be the first to try this if government space programs do not do it. Pushing an asteroid seems a strange thing to do, but when we someday find an asteroid on a collision course with the Earth, it may well be that this knowledge saves humanity. – The Conversation | Rappler.com

Michael B. Lund is a Postdoctoral Fellow in the Department of Physics and Astronomy at Vanderbilt University

This article appeared in The Conversation.