What planets are visible to the naked eye from Mars?

Question

Here on Earth we are able to see some other planets, Mars & Venus etc, with the naked eye on a fairly regular basis thanks to the distance between the planets.What about from Mars? What planets would be visible to the naked eye on a regular basis from Mars?Earth would obviously be one of them, as we can see it, but are any other planets close enough to mars at any point to be visible?

Answer 1

Planets can be seen from the surface of Mars much like they can be on Earth. The main factor in what can and can't be seen is distance. Astronomical Units (AU) are a useful measurement for distances in the solar system. 1 AU is the average distance of the Earth from the sun (it varies slightly due to the non quite perfectly circular orbit). On average Mars is about 1.5 AU from the sun while Jupiter (the next planet outward from Mars) is at a distance of just over 5 AU. From Earth we can see Mercury and Venus in the sky with the naked eye but not far from the sun in the sky since they are inward towards the sun in our solar system. The best time to spot them is a little before sunrise or a little after sunset. From Mars Earth would be visible in the same way, toward the direction of the sun, as would Mercury and Venus.

From Earth the more distantly visible naked-eye planets are Jupiter and Saturn. Technically Neptune can be seen under certain circumstances but it is difficult. Compared to the distance to Jupiter from the sun, the Earth and Mars are nearly in the same neighborhood so the same planets can be seen in the outer solar system from both planets. These planets can be appear at any point in the night sky depending on where they are in their orbit at any given moment and the orientation of the viewing planet and its current position in orbit around the sun.

In summary, all the same planets would be visible form Mars as from Earth but of course Earth would be one of the planets visible inward toward the sun along with Mercury and Venus, and the outward planets of Jupiter, Saturn, and Neptune (under just the right conditions) would also be visible at the right times of the Martian year when they are oriented in the direction the nighttime side of Mars faces at any particular point in its orbit.