Apophis Whizzes Past Earth, Bigger than Expected: Why is it called 'doomsday asteroid?'
By Arlene Paredes | January 10, 2013 11:13 AM EST
Apophis, an asteroid first spotted in June 2004, passes by Earth Jan. 9 (00:00 UTC Jan. 10). This near-Earth space object was once called "doomsday asteroid," but scientists confirm this 2013 approach happens at a relatively safe distance. However, it has just been announced Wednesday the asteroid was actually bigger than previously believed.
What Time Will Apophis Pass By?
Apophis webcasts on Slooh.com will start from 4 PM PST / 7 PM EST / 00:00 UTC (Jan. 10). It will be less than 9.3 million miles (15 million kilometers) away from Earth in its approach Wednesday. Meteorwatch.org is also featuring Slooh's webcast, which you can watch for free to observe the Apophis flyby.
Is Apophis a 'doomsday asteroid?'
On social networks like Twitter, Apophis is referred to as "doomsday asteroid." But there is no reason to worry, at least not this year. Apophis is a near-Earth asteroid by astronomical standards, but at a distance of millions of miles away, scientists are not worried. However, back in 2004, there was at least a bit of anxiety within the science community over Apophis.
Initial studies and estimates of Apophis' orbit showed it could potentially impact Earth or the Moon in its approach in 2029. The probability of such an occurrence was only at 2.7% but no one would be complacent. Later, scientists heaved a sigh of relief when it was found there was much less risk of an impact than previously learned. By late 2009, NASA recorded the probability of an impact on April 13, 2036 is around 1 in 250,000.
Apophis is bigger than previously thought
However, the latest news about Apophis indicates the "doomsday asteroid" is bigger than previously believed.
"ESA [European Space Agency] officials announced that its infrared Herschel Space Observatory has discovered that Apophis is about 1,066 feet (325 meters) wide, nearly 20 percent larger than a previous estimate of 885 feet (270 m)," Space.com reported.
In a statement, Apophis study leader Thomas Müller of the Max Planck Institute for Extraterrestrial Physics in Germany said:
"The 20 percent increase in diameter ... translates into a 75 percent increase in our estimates of the asteroid's volume or mass."
Further announcements regarding Apophis are expected from scientists in the coming years. In 2029, Apophis will approach Earth not from millions of miles away. It will be closer to Earth than the moon.
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