On June 27, the mountain-sized asteroid 2011 UL21 will pass within 5 million miles of Earth. It is one of the largest space rocks to come this close to our planet in 125 years.
A massive asteroid will approach the earth PHOTO: Shuterstock
How big is the asteroid?
According to yahoo!news, 2011 UL21 orbits the Sun once every three years and is estimated to be between 1.1 and 2.4 miles across, according to SpaceReference. That makes it larger than 99 percent of known near-Earth asteroids, according to the European Space Agency. It was designated as a “potentially dangerous asteroid”because of its size.
“Tpotentially dangerous asteroid ermen (PHA) is a precise formal definition that refers to minor planets larger than about 140 meters that can approach within 7.5 million kilometers of Earth,” said Virtual Telescope Project Scientific Director Gianluca Masi.
How close will asteroid 2011 UL21 get to Earth?
The space rock is expected to zip past our planet at about 58,000 miles per hour. It will come within less than 4.1 million miles of Earth, according to NASA’s Jet Propulsion Laboratory, qualifying it as a potentially hazardous object. However, it will be about 17 times farther from Earth than the Moon.
A massive ‘planet killer’ asteroid will come very close to Earth PHOTO: ESA
Is asteroid 2011 UL21 the largest to come close to Earth?
2011 UL21 is big, but it pales in comparison to other space rocks that have impacted Earth’s history. It is probably at least 10 times smaller than the Vredefort asteroid, the largest space rock ever to hit Earth.
Also about five times smaller than the space rock that destroyed the dinosaurs about 66 million years ago.
Is the asteroid a threat?
Although 2011 UL21 is not expected to collide with Earth anytime soon, its size is enough to permanently alter the course of the planet’s history if it did. For this reason, asteroids of this size are sometimes called “planet killers”as the damage could cross continents and release enough debris into the atmosphere to cause major environmental changes worldwide.
How close will asteroid 2011 UL21 get to Earth?
The space rock is expected to zip past our planet at about 58,000 miles per hour. It will come within 4.1 million miles of Earth, according to NASA’s Jet Propulsion Laboratory, qualifying it as a potentially hazardous object. However, it will be about 17 times farther from Earth than the Moon.
How can you watch asteroid approach live?
If you’re interested in watching the asteroid approach, you can watch a free live stream from the Virtual Telescope Project that will show the view of the asteroid from the Bellatrix Astronomical Observatory in Ceccano, Italy. The stream begins on June 27 at 4:00 p.m., and the approach is expected to occur about 15 minutes later.
If you have a good telescope, you might even be able to see the asteroid just by looking up at night. It will be brightest on June 28 and 29 and will be visible throughout the Northern Hemisphere.
When will it approach Earth again?
2011 UL21 won’t come this close to Earth until 2089. At that time, the asteroid will come within 1.7 million miles of Earth, more than two and a half times closer than it will come this week This one.
