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Supermoon – Super Moon – Super Full Moon

A supermoon hapens when there's a full Moon or new Moon at the same time as the Moon's closest approach to the Earth. When this happens, the Moon may seem bigger and brighter.

Wat arun in night with super full moon
A supermoon can occur more than once a year.
A Super Full Moon looks no different than any other full moon, it's just a bit closer to Earth.
©bigstockphoto.com/Prasit Rodphan

This is just an illusion - there is no actual difference in the size of a supermoon and an ordinary full Moon.

The next Super Full Moon will be on Monday, September 28, 2015.

The distance from moon to Earth varies throughout the month and year. On average the distance is about 238,000 miles (382,900 kilometers). During a month, when the moon is farthest away from Earth it's called apogee, when the moon is closest to Earth it is called perigee. When the full moon or New Moon coincides with being closest to Earth, or perigee, it is called a supermoon. The term Micro Moon refers to a full moon that occurs when the moon is farthest from Earth, or apogee.

Defining a supermoon

There are no universal rules as to how close the moon must be to qualify as a supermoon or a micro moon. timeanddate.com uses the following definition:

  • If a full moon or new moon is closer than 360,000 kilometers (ca. 223,694 miles) at perigee, it is considered a supermoon.
  • If a full moon occurs when the Moon is farther than 400,000 kilometers (ca. 248,548 miles) at apogee, it is considered to be a Micro Moon.
  • YearDate
    2015Sunday, September 27
    2016Monday, November 14
    2017Sunday, December 3

Technical name for a supermoon

The technical term for a supermoon is “perigee-syzygy of the Earth-Moon-Sun system”. In astronomy, the term “syzygy” refers to the straight-line configuration of three celestial bodies, which also occurs during a full moon.

Moon phases

Do supermoons trigger natural disasters?

Although the sun and the moon’s alignment cause a small increase in tectonic activity, the effects of the supermoon on Earth are minor. Many scientists have conducted studies and haven’t found anything significant that can link the supermoon to for example natural disasters, as some astrologers claim.

According to NASA, the combination of the moon being at its closest and at full moon, should not affect the internal energy balance of the Earth since there are lunar tides every day. There is a small difference in tidal forces exerted by the moon’s gravitational pull at lunar perigee. However, they are too small to overcome the larger forces within the planet.

Typical effects of the Moon

Moon is Earth’s only natural satellite and the second brightest object in the sky after the sun. In synchrony with Earth, the moon spins at about the same speed and direction as it orbits around the Earth. This means that the same side always faces Earth, and the half of the moon's surface that is facing outwards is never directly visible from Earth.

The tides on Earth are mostly generated by the intensity of the moon’s gravitational pull from one side of the Earth to the other. The moon’s gravity can cause small ebbs and flows in the continents called land tides or solid Earth tides. These are greatest during the full and new moons because the sun and moon are aligned on the same or opposite sides of the Earth.

Topics: Astronomy, Moon

In this Article


All about the Moon

  1. Moonphases worldwide
  2. Phases of the Moon
  3. What is a Supermoon?
  4. Micro Moon versus Supermoon
  5. Is a Blue Moon blue?
  6. The Moon's orbit
  7. What is a Black Moon?
  8. What are Moonbows?
  9. Full Moon names

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