Every few years the planets appear in a line
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Almost all the planets in the solar system are marching through the night sky in single file. This planetary alignment, sometimes called a planet parade, will include all the planets of the solar system except Mars, as it is currently on the opposite side of the sun from Earth and therefore not visible.
Alignments like this only happen every few years, when all the planets’ orbits happen to bring them to the same side of the Sun at the same time. All of their orbits are different — Mercury takes 88 Earth days to circle the Sun while Neptune takes about 165 Earth years — so planetary alignments are a lucky coincidence of geometry and orbital dynamics.
Sometimes they happen relatively close together – February 2025 saw a so-called “great alignment”, where all seven planets were visible at the same time – and sometimes years go by without a single one.
During a planetary alignment, the planets trace a line across the sky along what is called the ecliptic. This is the same line that the sun follows across the sky during the day, although the inclinations of the planets’ orbits mean they don’t line up perfectly. From outside the solar system, the planets would not appear in a line – it is an optical illusion due to the fact that all the planets orbit in the same plane.
The alignment will be visible over a range of dates depending on where you are in the world, but February 28 and March 1 will be the best days to see it in most places. Find a spot with an unobstructed view of the western sky and as little light pollution as possible, and watch for the parade.
The best time to see the planet parade on February 28 will be less than an hour or so after sunset: Mercury’s orbit close to the sun means it will sink below the horizon shortly after the sun does. Just after sunset, both Mercury and Venus will be visible low on the western horizon. Saturn and Neptune will be just above them, then Uranus and finally Jupiter relatively close to the almost full moon.
While Mercury, Venus, Saturn and Jupiter should be visible to the naked eye, binoculars will be needed to spot Uranus, and a telescope to see Neptune, because they are so far away.
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