Mars closest to Earth

You’ll have to hope for clears skies tonight as Mars will be the closest to Earth it has been since November 2005. That said, it will not appear to be any more than a rather bright ruddy point in the sky unless you’re viewing it with a decent telescope. It will be a mere 75.3 million kilometres away.

As EarthSky explains, the point of clostest proximity is not when lie directly between the Sun and Mars, because plenatary orbits are not circular they are elliptical and those orbits are not all in a nice, neat plane as is so often depicted in the kind of space and astronomy books we read as kids (and even adults):

“If both the Earth and Mars circled the sun in perfect circles, and on the same exact plane, the distance between Earth and Mars would always be least on the day of Mars’ opposition. But we don’t live in such a perfect universe. Planets have elliptical orbits and a perihelion (closest point) and aphelion (farthest point) from the sun. Mars orbit around the sun takes 687 days in contrast to 365 days for Earth. It has a year nearly twice as long as ours. Earth’s closest point to the sun comes yearly, in January. Mars will be closest to the sun next on October 29, 2016.”

But, for a really close encounter you will have to wait until 2018, when Mars will come to within 57.6 million kilometres. The red planet was closers still at 55.8 million km back on the 27th of August 2003.

EarthSky has a handy starchart showing the positions of Mars, Saturn and the star Antareslying in the constellation Scorpius. Fingers crossed for a clear night…