Astronomers: Massive asteroid Apophis will not strike Earth in 2036
You can breathe a sigh of relief.
A team of international astronomers announced late Wednesday that a massive 900-foot asteroid will not strike Earth in 2036, despite a close brush in 2029.
“Goldstone single-pixel observations of Apophis have ruled out the potential 2036 Earth impact,” says Jon Giorgini, a dynamicist at NASA’s Jet Propulsion Laboratory. “Based on revised orbit calculations, Apophis will then come no closer than about 14 million miles — and more likely miss us by something closer to 35 million miles.”
The massive asteroid, which made its most recent pass by Earth late Wednesday, was never a serious threat, according to astronomers. When it was first discovered in 2004 by observers Roy Tucker, David Tholen, and Fabrizio Bernardi, scientists placed the odds at 1 in 45. New projections show the asteroid passing by Earth in 2029 at a distance of 20,000 miles, well within the lunar orbit.
The latest projections follows in the wake of recent observations, which pegged the asteroid’s size nearly 20 percent larger than previsouly thought. Previous estimates put the asteroid’s average diameter at 885 feet (270 meters). The latest estimates place the asteroid’s size closer to 1,060 feet (325 meters) across, according to NASA.
In addition, astronomers had the opportunity to analyze the heat emitted by Apophis. Using the Herschel Observatory — operated by the European Space Agency — astronomers provided a new estimate of the asteroid’s albedo — a measure of its reflectivity– of 0.23. This value means that 23 percent of the sunlight falling onto the asteroid is reflected; the rest is absorbed and heats up the asteroid. The previous albedo estimate for Apophis was 0.33.
While Earth was never in any serious danger, astronomers at NASA announced plans earlier this week to track the asteroid. The team of astronomers reportedly employed deep-space radars at Goldstone, located in the Mojave desert in California, and Arecibo in Puerto Rico to scan the asteroid. The team said the additional research would likely lead to the elimination of any threat poised by the massive space rock.
“Using new measurements of the asteroid’s distance and line-of-sight velocity, we hope to reduce the orbital uncertainties and extend the interval over which we can compute the motion into the future,” NASA Jet Propulsion Laboratory’s Lance Benner said in an email to the Associated Press at the time.
“It’s possible that the new measurements improve the orbit to the point that we can completely rule out an impact.”
The possibility of an impact with Earth drew widespread attention to the asteroid. At one point the asteroid was dubbed a “doomsday asteroid” because of a 2004 study that predicted a 2.7 percent chance of the space rock hitting Earth. Apophis is also the name of an Ancient Egyptian mythological demon, in Greek known as Apophis.