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September astro outlook: Fourth supermoon and Neptune appears

03:00 PM
September 2, 2023

September astro outlook
Fourth supermoon and Neptune appears

star-gazing

September is not the most active month for stargazers, but it does deliver the autumn equinox, ushering in the new season.

The month begins with a new moon on September 15 offering dark skies perfect for those wanting to see fainter objects in the night sky.

Those faint objects will include Neptune in opposition on September 19, though only for those with powerful telescopes.

The furthest planet from the sun will be illuminated by the star on this day, offering the best chance to spot the gas giant.

A few days later, we find Mercury at its greatest western elongation. On September 22, the closest planet to the sun will be visible just before dawn. Look towards the eastern horizon before sunrise.

A day later, and the autumnal equinox heralds the beginning of astronomical autumn. This year, the equinox takes place on September 23, at 2:49 a.m. EDT (September 22, 11:49 p.m. PDT).

At the equinox the sun will shine directly on the equator, giving us an almost equal number of hours of day and night. In the Southern Hemisphere, this is the spring equinox.

Finally, the month is rounded out by the year's fourth, and final, supermoon. Rising on the evening of September 29, this full moon is dubbed the harvest, or corn, moon.

The closest full moon to the equinox is always referred to as the harvest moon. This year it becomes a supermoon as it arrives in parallel with the moon's perigee, the closest point to Earth in its orbit.

If you head out to capture the supermoon, have a telescope powerful enough to spot Neptune, or use the darkness of the new moon for a spot of stargazing... we would love to see what you capture.

Tap the image icon in the app or use our dedicated uploader.

Tips: Astrophotography with your phoneread more
Weather & Radar USA editorial team
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