NASA reveals new images of a "planet killer" asteroid and its moon
NASA has published new images of an asteroid that flew past Earth last month, as reported by Live Science. The asteroid, referred to as a "planet killer," is the size of a mountain and has a mysterious and unexpected companion.
3:34 PM EDT, July 10, 2024
Live Science reminds us that the "planet killer," actually asteroid 2011 UL21, is a potentially dangerous object that moves close to Earth. It orbits the Sun once every three years and approaches our star at a distance of 1.3 astronomical units (AU), or about 120.9 million miles. The space rock was closest to Earth in 2011, about 4.1 million miles away. According to Live Science, this makes 2011 UL21 one of the 10 largest asteroids to have passed so close to Earth since 1900.
If it hit Earth, it could cause a climate disaster
The somewhat terrifying name of the 2011 UL21 is due to its size. Scientists previously estimated that the "planet killer" has a width of about 1-2 miles, making it larger than 99 percent of asteroids near Earth. Such large dimensions would allow asteroid 2011 UL21 to destroy an entire continent upon impact effectively and, as Live Science explains, cause catastrophic climate changes across the globe. However, scientists reassure us that the "planet killer" is not expected to hit Earth in the future.
In theory, 2011 UL21 does not surprise scientists. However, recent discoveries by NASA revealed that the space rock is smaller than previously assumed. Moreover, it has a mysterious companion.
New photo taken by NASA
Thanks to a photo taken at the American space agency's Goldstone Deep Space Communications complex in California and observations of the "planet killer's" flight using the Goldstone Solar System Radar telescope, scientists could accurately reflect radio waves from the asteroid's surface. This revealed two things. First and foremost, the 2011 UL21 is likely smaller than scientists previously estimated. According to the latest findings, the "planet killer" has a width of 1 mile.
The second valuable discovery was identifying an object next to the asteroid. It turns out that 2011 UL21 moves through space accompanied by a smaller planetoid or moon, orbiting it at about 2 miles.
"It is believed that about two-thirds of planetoids of this size are binary systems, and their discovery is particularly important because we can use measurements of their relative positions to estimate their mutual orbits, masses, and densities, providing key information about how they may have formed," said Lance Benner, a NASA scientist who participated in the observations of the 2011 UL21 binary system.
