Our tides are caused by the gravitational pull of the Moon and the Sun and the Earth’s rotation. Supermoons appear to be 14% larger and 30% brighter than a micromoon. However, the difference won’t be easily noticeable to the naked eye and a side by side photographic comparison is the only way to really see it.Ĭomparison between a micromoon and a supermoon. The full Moon will look slightly bigger if it occurs during perigee (sometimes called a supermoon) and slightly smaller at apogee (a micromoon). The supermoon and micromoonīut do the two distances affect us in any way? Not really. Note that the Earth is not at the very centre of the orbit and that the eccentricity of the orbit has been exaggerated here! Credit: NASA/Luc Viator/Affelia Wibisono. The Moon’s elliptical orbit with the distances at apogee and perigee. These two figures differ by 42 592 km (26 465 miles) - more than three times larger than the diameter of the Earth! The average distance between the Earth and the Moon is 384 400 km (238 855 miles). The distance between them is only 363 104 km (225 623 miles). On the other hand, when the Moon is at perigee (‘peri’ means ‘near’), the Moon is at its closest approach to the Earth. Apogee, perigee and average distance - the distance to the Moon explainedĪstronomers tend to talk about three different numbers when talking about the distance between the Earth and the Moon.Īt its furthest point from the Earth, the Moon is about 405 696 km (252 088 miles) away and astronomers say that the Moon is at apogee (‘apo’ means ‘away’). It is located at one of the foci of the Moon’s elliptical orbit, so is closer to one edge of the orbit than the other. Furthermore, the Earth is not at the very centre of the Moon’s orbit either. The eccentricity of the Moon’s orbit is 0.05. Mercury’s is the most eccentric with a value of 0.2. Venus’ orbit is the least eccentric out of all of the planets in our Solar System and closest to a circle, with a value of 0.007. In fact, a circle can be thought of as a special kind of ellipse that has an eccentricity of 0. The closer the eccentricity is to 0, the closer the orbit is to a circle. This is expressed by a number that is between 0 and 1. Astronomers can measure how near to a perfect circle an orbit is by calculating its 'eccentricity'. Some are very close, but they are all at least slightly elliptical in shape.
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