In the summer of 2004, planetary defence scientists and space observers at the Kitt Peak National Observatory discovered a medium-sized space rock heading towards earth. In December later that year, scientists at NASA were able to determine its diameter to be about 390 meters. Its mass estimated around 8.3×10^10 kg. What they also determined was that this asteroid had a 2.4% impact risk with the earth. Asteroid Apophis made a name for itself.
Scientists regularly discover similar huge space rocks called asteroids. So what made this discovery so interesting, or rather so worrisome? Well, the observers were able to determine that Apophis was travelling in a collision course towards earth. Not only that but its collision measurements determined its collision date to sometime around 2029. A mere 15 years after its discovery.
Hundreds of independent observations were conducted for almost two years after its discovery. It wasn’t until 2006 that Apophis was finally lowered to Torino scale 0 from the much more dangerous level 4 it had been rated at in 2004.
We now know that Apophis has a diameter of 370 meters and a mass of
6.1×10^10 kg. It takes roughly 324 days to orbit the sun and it comes as close as 0.922 astronomical units (AU).
The asteroid will certainly visit us soon, on April 13th, 2029 to be exact, and at a distance of 31,200 Km. Although, its visit won’t be as dangerous as previously considered. It will offer a great learning opportunity for scientists to study an asteroid at such a short distance for the first time.
You can track Apophis, as well as many other asteroids detected so far at spacein3d.com.