Opinion Brief

Is an asteroid stalking Earth?

We are not alone: A newly discovered asteroid is following Earth, tracing our orbit as we circle the Sun

The image: Scientists have known for many years that asteroids often follow planets, moving in the same orbit around the sun. These so-called "Trojan asteroids" have been spotted tagging alongside Jupiter, Mars, and Neptune. Earth, however, was believed to be free of these celestial stalkers — until now. Astronomers from Athabasca University in Canada, using data from an infrared NASA telescope that's orbiting the Earth, discovered an asteroid tracking us from just 50 million miles away. (See an image at right, and an artist's rendering below.) Earth's Trojan asteroid is usually obscured by the light from the Sun, which is why it's only recently been discovered. Besides its orbit, researchers know very little about this asteroid, named 2010TK7. It's estimated to be roughly 1,000 feet across, "about the size of a small neighborhood," says astronomer Martin Connors, as quoted by the Australian Broadcasting Corp. 

The reaction: "Fascinating," says Jonathan Amos at BBC News. Trojans like 2010TK7 "would make possible targets for astronaut missions." And finding this Trojan asteroid means there are probably other asteroids following Earth, just waiting to be discovered. In the meantime, there's no need to worry that our little asteroid will collide with Earth, says Charles Q. Choi at Space.com. Because 2010TK7 is expected to maintain a stable orbit for at least 10,000 more years, it won't get "any closer than 12.4 million miles, which is more than 50 times the distance from Earth to the moon." See for yourself:

Image credit: Paul Wiegert, University of Western Ontario, Canada

Recommended

Smart telescopes offer a 'transformative' experience for citizen scientists
Scott Kardel.
out of this world

Smart telescopes offer a 'transformative' experience for citizen scientists

Scientists sequence Beethoven's DNA, 200 years after his death
Ludwig van Beethoven
Looking into Ludwig

Scientists sequence Beethoven's DNA, 200 years after his death

Essential molecules for life may have been 'delivered' to Earth from space
Asteroid Ryugu.
alien invasion

Essential molecules for life may have been 'delivered' to Earth from space

3 key graphics from the U.N. climate report
An illustration of a wet and dry Earth with a climbing graph line in the middle
Feature

3 key graphics from the U.N. climate report

Most Popular

DeSantis' no good, very bad week
Ron DeSantis at a podium
Behind the scenes

DeSantis' no good, very bad week

Russia's spring Ukraine offensive may be winding down amid heavy losses
Ukrainian tank fires near Bakhmut
Attrition

Russia's spring Ukraine offensive may be winding down amid heavy losses

CDC warns of deadly fungus in U.S. health facilities
Candida auris.
sounds like a show we know ...

CDC warns of deadly fungus in U.S. health facilities