IMAGE: These images represent radar observations of asteroid 99942 Apophis on March 8, 9, and 10, 2021, as it made its last close approach before its 2029 Earth encounter that will see the object pass our planet by less than 325 000 kilometres. CREDIT: NASA/JPL-Caltech and NSF/AUI/GBO
Time to talk about space rocks and how they sometimes attack.
Several years ago, there was a whole lot of excitement that Earth might get hit by the asteroid Apophis if its orbit turned out to be just so. Well, March 8-10, its orbit and Earth’s came together, but at a healthy distance, and new measurements determined that it will not hit us in 2029, 2036, or even in 2068. Beyond that, there is still a risk. This 350-meter across asteroid is just big enough to do a lot of damage if it collides, and its Earth-crossing orbit crosses a bit too close to Earth for comfort.
Earth-crossing just means the orbits intersect; it doesn’t mean the objects intersect. In a best-case scenario, an asteroid crosses Earth’s orbit when the Earth is far away, like the other side of the Sun far away. Apophis, however, likes to get close and will endanger ...