The planet Mars will reach perigee, the closest point on its orbit to Earth, slightly after 1.30 pm on Sunday 12 January 2025, when it will be 0.67 AU (i.e. 0.67 times the average distance between the Earth and the Sun) from the Earth. Mars orbits the Sun at an average distance of 1.52 AU, but at a slower speed (the speed at which a body orbits another body is determined by the distance between them, with a greater distance resulting in a slower speed), so that a Martian year is 687 days long. Most outer planets (i.e. planets which are in our Solar System, but further from the Sun than the Earth) tend to be at their closest to the Earth close to when they are at opposition (i.e. when they are directly on the opposite side of us to the Sun), but because the orbits of all planets are elliptical (Mars veries between 1.38 and 1.67 AU from the Sun, while the Earth varies between 1.47 and 1.52 AU from the Sun) these seldom match up, with the effect that this year Mars will be at opposition four days after its perigee, on Thursday 16 January.
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While the relative positions of the planets have no direct influence on life on Earth, the perigee and opposition of a planet do present the best oportunites for observations of by Earth-based observers. Between 12 and 16 January 2025, Mars will appear as a bright object in the constellation of Gemini, although a Full Moon on Monday 13 January, in the constellation of Cancer, will hamper viewing somewhat.
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