Lunar Perigee and Apogee and the Moon's Orbit
Ever heard the terms perigee and apogee? The Moon’s orbit periodically grows rounder and then more oval; it is never a perfect circle. Therefore, sometimes, the Moon is nearer to the Earth or farther from Earth. The news media will often use the terms “Supermoon” and “Micromoon.” Learn more.
What are Perigee and Apogee?
A simple definition:
- The point at which it is nearest Earth each month is called its perigee (this varies throughout the year). This is sometimes called a “Supermoon” by the news media because the Moon is slightly larger and brighter. This effect can be enhanced by the “Moon Illusion.”
- The point at which the Moon is farthest from Earth each month is called its apogee (this varies throughout the year as well). This is sometimes called a “Micromoon” by the news media, as it is slightly smaller (up to 14%) and dimmer (around 30%) than a Supermoon.
According to NASA, “During every 27-day orbit around Earth, the Moon reaches both its perigee, about 226,000 miles (363,300 km) from Earth, and its farthest point, or apogee, about 251,000 miles (405,500 km) from Earth.”
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When are Perigee and Apogee?
Lunar Perigees and Apogees in 2026
| Month | Closest Approach (Perigee) | Furthest Apart (Apogee) |
|---|---|---|
| January | Jan 1 | Jan 13 |
| February | Feb 24 | Feb 10 |
| March | Mar 22 | Mar 10 |
| April | Apr 19 | Apr 7 |
| May | May 17 | May 4 |
| June | Jun 14 | Jun 1, Jun 28 |
| July | Jul 13 | Jul 25 |
| August | Aug 10 | Aug 22 |
| September | Sep 6 | Sep 18 |
| October | Oct 1, Oct 28 | Oct 16 |
| November | Nov 25 | Nov 13 |
| December | Dec 24 | Dec 11 |
Perigee and Apogee Also Affect the Tides
During the final quarter of the 20th century, the Moon was as close to Earth as 216,500 miles (surface to surface) at its most extreme perigee and as far away as 247,700 miles at its most extreme apogee. At perigee, tidal ranges are increased; at apogee, they are decreased.
To a lesser degree, the Sun has a similar tidal effect, a consequence of its location just 91.5 million miles away in early January but some 94 million miles distant in July.
The punctual tide draws up the bay
With ripple of wave and hiss of spray.
–Susan Coolidge, American writer (1835-1905)
It would seem to make sense, wouldn't it? But actually the hotter/cooler weather, and seasons, are caused by the angle of the incoming sunlight. The more direct an angle, the more heat we will receive. Earth is tilted at a 23.5 degree angle to the plane of its orbit; this tilt can be toward the Sun (summer in Northern Hemisphere), away from the Sun (winter in the Northern Hemisphere), or neither (spring and fall equinoxes). Because of this tilt, at any one time, the amount and angle of sunlight will differ in various locations on the planet. And this distribution will change as Earth travels along in its orbit.
From January's perihelion (when Earth is closest to the Sun), we move farther away from the Sun each day. In January, the angle of the Sun’s rays were low in the Northern Hemisphere, so the Sun’s energy was distributed over a larger area, weakening its intensity in any one place (sort of like the light from a tilted flashlight on a surface); the days were also shorter than they are now, so that we received less energy from the Sun.
At the spring and fall equinoxes, we are neither tilted toward nor away from the Sun, which means that at the Equator, the Sun’s rays are coming in at about a 90 degree angle—so the energy there is concentrated along a smaller surface. However, at the higher latitudes, the Sun’s rays are being received at more of an angle, so we’re getting less intense rays than the Equator, and things are a bit cool. As the spring days progress toward the summer solstice, the angle of the Sun’s rays become more direct, and the days are also getting longer, which increases the amount of energy that we are receiving. So, we’re getting more energy as spring progresses to summer, resulting in warmer temperatures. Hottest temperatures are usually a bit after the summer solstice, because it takes a while for the water and land to reach a certain rate of absorbing vs. releasing the Sun's energy.
You can find the times of perigee and apogee for the Moon on the appropriate dates of the right-hand pages of The Old Farmer's Almanac, both print and digital versions. These times/dates have been converted to Eastern Time (National, Canadian, Southern editions) or Pacific Time (Western edition).
For a list of perigee and apogee dates online, you might go to the following; please keep in mind that these dates are listed in Universal Time (at Greenwich, England) and would need to be converted to your local time zone.
http://fourmilab.ch/earthview/pacalc.html
We have not found information about how perigee and apogee might affect people, at least nothing conclusive, but good luck with your research!
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