Planetary Alignment: A Spectacular Celestial Event
Every few years, the planets appear in a line
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Nearly all of the planets in the solar system are about to march through the night sky in a single-file line. This planetary alignment, sometimes called a planet parade, will include all of the solar system’s planets except Mars, as it is currently on the opposite side of the sun from Earth and therefore not visible.
Alignments like this only occur every few years, when all the planets’ orbits happen to carry them to the same side of the sun at the same time. All of their orbits are different lengths – 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 once – and sometimes years go by without a single one.
During a planetary alignment, the planets trace a line across the sky along what’s called the ecliptic. This is the same line that the sun follows across the sky during the day, although the tilts of the planets’ orbits make it so that they don’t line up perfectly. From beyond the solar system, the planets would not appear in a line – that is an optical illusion due to the fact that all of the planets orbit in the same plane.
The alignment will be visible across a range of dates depending on where you are in the world, but 28 February and 1 March will be the best days to see it in most places. Find a spot with a clear view of the western sky and as little light pollution as possible and look out for the parade.
The best time to see the planet parade on 28 February will be less than an hour or so after sunset: Mercury’s orbit close to the sun means that it will sink below the horizon shortly after the sun does. Right 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 nearly-full moon.
While Mercury, Venus, Saturn and Jupiter should be visible to the naked eye, binoculars will be necessary to spot Uranus, and a telescope to see Neptune, because they are so far away.
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