If you are blessed with clear skies this week, you can catch Mars at its best and brightest. The Red Planet and Earth are currently at the closest distance they will be for another 15 years. It can be seen this week as a clear red dot close to the Moon, the crimson hue of the celestial body visible even without binoculars or a telescope.
The two planets will be roughly 62.1 million kilometers (38.6 million miles) apart, with the closest point occurring on Tuesday, October 6. Mars won't get as close to us again until the year 2035.
It's not the closest that it has gotten in recent years – in 2018, Earth and Mars were just 57.6 million kilometers (35.8 million miles) from each other – but it's still pretty close.
The closest distance recorded was back in 2003 when Mars was 55.7 million kilometers (34.6 million miles) away. This distance was the closest the two planets have been in 60,000 years, and we will have to wait until August 28, 2287 for this record to be broken.
This is still not the closest distance possible. That would happen when Earth is at its aphelion, the furthest point from the Sun in a planet’s orbit, and Mars is at its perihelion, the closest point to the Sun. That special alignment would take the two planets to a distance of just 54.6 million kilometers (33.9 million miles), but it has never been recorded yet.
The opposite of the closest approach is when the two planets are at their aphelion on opposite sides of the Sun. The furthest distance that they can be is about 401 million kilometers (250 million miles) apart.
The next close approach will be in two years, but the gap between the two planets will become larger and larger until 2029. Despite this, every close approach is an exciting period for astronautics. Space agencies around the world time the launch of missions to Mars to occur when the distance between the two planets is smallest, so the travel time is shortest. Three missions were sent this summer, including NASA’s Perseverance rover.
The Rosalind Franklin Rover, a joint mission from the European Space Agency and Russia's Roscosmos, was also due to launch this summer but had to be put back due to the pandemic. It is expected to fly in the next launch window in late 2022.