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When is the May full moon?

The moon is waxing toward full on this Sunday night. It’ll still be a touch shy of full for most – but not all – of the world on Monday night. As seen from around the globe, the bright “star” near the moon is Jupiter.

Man and moonset by Martin Marthadinata in Surabaya, East Java, Indonesia.

In order to appear full to us on Earth, the moon has to be opposite the sun in our sky. That’s why every full moon rises in the east around sunset and climbs highest up for the night midway between sunset and sunrise (around midnight). Sunday night’s moon is not quite full. You’ll find it ascending in the east as the sun sets in the west. The May 2018 full moon comes officially on May 29, but for some – those far to the west in the world’s time zones (western North America or islands in the Pacific) – the moon is closer to full on the night of May 28.

On both of those nights, the moon will set closer to the time of sunrise. It’ll appear quite full and shine almost all night long.

And – for all of us around the globe – the bright object near the moon now is the largest planet in our solar system, Jupiter.

The moon has been moving along the ecliptic – pathway of the sun, moon and planets in front of the constellations of the zodiac, represented on this chart as a green line – for several nights. Let the moon guide you to Jupiter on these nights.

Technically speaking, the moon is full at the instant it’s 180 degrees from the sun in ecliptic longitude. That official moment of full moon happens on May 29, 2018, at 14:20 UTC. At North American and U.S. time zones, that translates to 11:20 a.m. ADT, 10:20 a.m. EDT, 9:20 a.m. CDT, 8:20 a.m. MDT, 7:20 a.m. PDT, 6:20 a.m. Alaskan Time and 4:20 a.m. Hawaiian Time … in other words, midday or very early morning on May 29. Translate UTC to your time.

Hawaii and Alaska’s far-southwestern Aleutian Islands will be the only places in the U.S. that will be able to view the moon at the exact instant it turns full in May 2018. For these places, the full moon will sit low in the west before sunrise on May 29.

Meanwhile, in the world’s Eastern Hemisphere – Asia, Indonesia, Australia and New Zealand – the moon will reach that full moon instant after sunset May 29 (night of May 29-30). In New Zealand and along the east coast of Australia, the moon will reach it after midnight May 30.

Want to know the instant of full moon in your part of the world, as well as the moonrise and moonset times? Click here, remembering to check the moon phases plus moonrise and moonset boxes.

Worldwide map via the U.S. Naval Observatory. The day and night sides of Earth at the instant of full moon (May 29, 2018, at 14:20 UTC). The shadow line at left depicts sunrise May 29 and the shadow line at right shows sunset May 29.

Bottom line: Full moon – when the moon is 180 degrees from the sun in ecliptic longitude – happens on May 29, 2018, at 14:20 UTC.

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Read more: What are the full moon names?

Deborah Byrd

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