Comet Siding Spring’s encounter with Mars has been dubbed a “once-in-a-lifetime” event by researchers.
On Sunday, at 2:27 p.m ET, Siding Spring came within 87,000 miles of the red planet. That’s about one-third the distance between us and the moon. All seven spacecraft orbiting Mars, including three NASA orbiters, were moved into safer orbits. The orbiters were also planning on observing the comet as it rocketed past Mars at more than 126,000 mph.
How big is Siding Spring? It’s nucleus measures about 0.4 miles in diameter.