Quantcast
Connect with us

New telescope will scan the skies for asteroids on collision course with Earth

Published

on

Around sunrise on Feb. 15, 2013, an extremely bright and otherworldly object was seen streaking through the skies over Russia before it exploded about 97,000 feet above the Earth’s surface. The resulting blast damaged thousands of buildings and injured almost 1,500 people in Chelyabinsk and the surrounding areas. While this sounds like the first scene of a science fiction movie, this invader wasn’t an alien spaceship attacking humanity, but a 20-meter-wide asteroid that had collided with the Earth.

What is worrisome is that no one had any idea this 20-meter asteroid existed until it entered the Earth’s atmosphere that morning.

As an astronomer, I study objects in the sky that change in brightness over short time scales – observations that I use to detect planets around other stars. A large part of my research is understanding how we can better design and run telescopes to monitor an ever-changing sky. That’s important because the same telescopes I’m using to explore other star systems are also being designed to help my colleagues discover objects in our own solar system, like asteroids on a collision course with with Earth.

Near-Earth objects

A meteor is any chunk of matter that enters the Earth’s atmosphere. Before the Chelyabinsk meteor met its demise on Earth, it was orbiting our sun as an asteroid. These rocky objects are normally thought to be restricted to the asteroid belt between Mars and Jupiter. However, there are many asteroids throughout the solar system. Some, like the Chelyabinsk meteor, are known as near-Earth objects (NEOs).

Aerial view of Arizona Meteor Crater, September 2010.
Shane Torgerson, CC BY

The Chelyabinsk meteor likely came from a group of NEOs called Apollo asteroids, named after the asteroid 1862 Apollo. There are more than 1,600 known Apollo asteroids logged in the JPL Small-Body Database that have orbits that may cross the Earth’s path, and are large enough (over 140 meters), that they’re considered potentially hazardous asteroids (PHAs) because a collision with Earth would devastate the region hit.

ADVERTISEMENT

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

Searching for threats

The U.S. government is taking the threat of an asteroid collision seriously. In Section 321 of the NASA Authorization Act of 2005, Congress required NASA develop a program to search for NEOs. NASA was assigned the task of identifying 90 percent of all NEOs greater than 140 meters in diameter. Currently, they estimate that three-quarters of the 25,000 PHAs have yet to be found.

To reach this goal, an international team of of hundreds of scientists, including myself, is completing construction of the Large Synoptic Survey Telescope (LSST) in Chile, which will be an essential tool for alerting us of PHAs.

ADVERTISEMENT

Exterior view of the Large Synoptic Survey Telescope, which is still under construction.
Sublocation Cerro Pachón, Chile.

LSST Project/NSF/AURA, CC BY-NC-SA

With significant funding from the U.S. National Science Foundation, LSST will search for PHAs during its 10-year mission by observing the same area of sky at hourly intervals searching for objects that have changed position. Anything that moves in just one hour has to be so close that it is within our solar system. Teams led by researchers at the University of Washington and JPL have both produced simulations showing that LSST on its own will be capable of finding around 65 percent of PHAs. If we combine LSST data with other astronomical surveys like Pan-STARRS and the Catalina Sky Survey, we think we can help reach that goal of discovering 90 percent of potentially hazardous asteroids.

A photograph and a baseline design rendering mix, showing a view of the completed exterior building from the road leading up to the site.
LSST Project/NSF/AURA, CC BY-NC-SA

Preparing to avert disaster

Both the Earth and these asteroids are orbiting the sun, just on different paths. The more observations taken of a given asteroid, the more precisely its orbit can be mapped and predicted. The biggest priority, then, is finding asteroids that may collide with the Earth in the future.

ADVERTISEMENT

If an asteroid is on a collision course hours or days before it occurs, the Earth won’t have many options. It’s like a car suddenly pulling out in front of you. There is little that you can do. If, however, we find these asteroids years or decades before a potential collision, then we may be able to use spacecraft to nudge the asteroid enough to change its path so that it and the Earth don’t collide.

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

The ConversationThe B612 Foundation, a private nonprofit group, is also trying to privately raise money for a mission to redirect an asteroid, and they may be the first to attempt this if the government space programs don’t. Pushing an asteroid sounds like an odd thing to do, but when we one day find an asteroid on a collision course with Earth, it may well be that knowledge that will save humanity.

ADVERTISEMENT

Michael B. Lund, Post-doctoral researcher, Department of Physics & Astronomy, Vanderbilt University

This article was originally published on The Conversation. Read the original article.


Report typos and corrections to: [email protected]. Send news tips to: [email protected].
READ COMMENTS - JOIN THE DISCUSSION
Continue Reading

2020 Election

Democrats are on the verge of setting a ‘time bomb’ for any candidate who can defeat Trump

Published

on

If a new president takes over the White House in January 2021, he or she may quickly find that the Democratic Party that just won control of the executive branch left a loaded gun in the hands of the Republicans, who are all too eager to use it.

That should be the takeaway from reports about the budget negotiations between the House Democrats and the Trump administration. According to Bloomberg reporter Sahil Kapur, the parties are coalescing around an agreement to raise spending by $350 billion, offset that increase somewhat with about $75 billion, and extend the debt ceiling — now set to expire in the fall — to July 31, 2021.

Continue Reading

2020 Election

State Sen. Royce West enters Democratic primary to challenge John Cornyn

Published

on

State Sen. Royce West made it official Monday: He’s running for U.S. Senate, joining a crowded and unsettled Democratic primary in the race to unseat Republican John Cornyn.

“I’m battle tested,” West told supporters at a campaign launch event. “You’ve seen me in battle, and I’m ready today to announce my candidacy for the United States Senate.”

The Dallas attorney has been viewed as a potential primary contender for some time now, but he remained mum publicly on his plans. In June, West met with U.S. Senate Minority Leader Chuck Schumer, D-N.Y., where he reportedly had a “positive meeting” and signaled that he was likely to throw his hat in the ring. He filed the Federal Election Commission paperwork to formally launch his bid Friday.

Continue Reading
 

Facebook

Former NASA flight director Chris Kraft dies at 95

Published

on

NASA's first flight director Chris Kraft, who played a critical role in the American space race, has died just days after 50th anniversary celebrations for the first Moon landing, the agency said.

The 95-year-old joined NASA in 1958 and developed the planning and control processes needed for crewed space missions, creating the agency's Mission Control operations that were used to manage the first US manned spaceflight and the Apollo missions to the Moon.

"America has truly lost a national treasure today with the passing of one of NASA's earliest pioneers," said agency chief Jim Bridenstine in a statement announcing Kraft's death on Monday.

Continue Reading
 
 
 

Copyright © 2019 Raw Story Media, Inc. PO Box 21050, Washington, D.C. 20009 | Masthead | Privacy Policy | For corrections or concerns, please email [email protected]

close-image
Join Me. Try Raw Story Investigates for $1. Invest in Journalism. Escape Ads.
close-image