Moonrise, Moonset and Meridian Passing Times Calculator – Timehubzone (2024)

FAQs

What is the meridian passing of the Moon? ›

A meridian is a location's longitude (a line that runs from the North Pole to the South Pole of Earth). When we use the word meridian, it usually refers to the moment that the Moon crosses or passes a location's meridian; this marks the exact moment when the Moon reaches the highest position in the sky.

By subtracting the hour angle of the rising point from the local time of culmination of the rising point, we obtain the time (local to the station) of moonrise. By adding the hour angle of the setting point to the local time of culmination of the setting point we obtaii~ the time (local to the station) of moonset.

The exact times depend on the lunar phase and declination, as well as the observer's location. As viewed from outside the polar circles, the Moon, like all other celestial objects outside the circumpolar circle, rises from the eastern half of the horizon and sets into the western half due to Earth's rotation.

Because the Moon is constantly in motion, the time span from one moonrise or moonset to the next is a little longer than 24 hours. For example, if the Moon rises just before midnight on day 1, it may not rise again until just after midnight on day 3, meaning that day 2 does not have a moonrise.

The meridian passage is the moment when a celestial object passes the meridian of longitude of the observer. At this point, the celestial object is at its highest point. When the Sun passes two times an altitude while rising and setting can be averaged to give the time of meridian passage.

While one sunrise to the next is about 24 hours, one moonrise to the next is about 24 hours and 50 minutes. The extra 50 minutes are due to the Moon's orbit about the Earth. It therefore shouldn't be surprising that there are days where moonrise occurs shortly before sunrise and moonset occurs shortly after sunset.

In its most general sense, twilight is the period of time before sunrise and after sunset, in which the atmosphere is partially illuminated by the sun, being neither totally dark or completely lit. However there are three categories of twilight that are defined by how far the sun is below the horizon.

The Moon rises on an average 50 minutes later each day in Earth's skies due to the difference in Earth's rotation and Moon's revolution. Moon completes one orbit around Earth in 28 days, moving 13º every day. Hence, the Earth has to rotate an extra 13º every day after completing one rotation for the Moon to be visible.

It is the Earth's rotation on its axis that makes the moon rise in east and set in the west. The picture below is of the moon setting in the west behind the Sierra Nevada mountains in the morning.

What phase is the Moon in today? ›

The Moon Today: Waxing Gibbous.

The first probe to impact the surface of the Moon was the Soviet probe Luna 2, which made a hard landing on September 14, 1959, at 21:02:24 UTC. The far side of the Moon was first photographed on October 7, 1959, by the Soviet probe Luna 3.

Due to the variations in tilt from the earth we know that moonrise/moonset times vary. Is it possible that in any location on the earth one might see more than one moonrise or moonset in a given 24 hour period? Yes.

This shift means Earth has to rotate a little longer to bring the Moon into view, which is why moonrise is about 50 minutes later each day. As it rises at a later time, the Moon appears in a different part of the sky.

However, it takes our Moon about 29.5 days to complete one cycle of phases (from new Moon to new Moon). This is called the synodic month.

Thus, with respect to the background constellations the Moon will be about 13.2 degrees further East each day. Since the celestial sphere appears to turn 1 degree about every 4 minutes, the Moon crosses our celestial meridian about 13.2 x 4 = 52.8 minutes later each day.

The phase is as seen in the Northern hemisphere of the Earth. As the Moon orbits around the Earth, the half of the Moon that faces the Sun will be lit up. The different shapes of the lit portion of the Moon that can be seen from Earth are known as phases of the Moon. Each phase repeats itself every 29.5 days.

If the Moon does not pass through the meridian on a given date, the columns are empty. This occurs once every Moon cycle.

A meridian transit occurs when an object moves across the meridian – an imaginary great circle on the celestial sphere that passes through the celestial poles and an observer's zenith.