It's approximately 380,000 km or 240,000 ..more definition+, The mile (abbreviation: mi) is a unit of distance on land in English-speaking countries equal to 5280 feet, or 1760 yards (1.609 kilometers). {\textstyle \Delta _{\oplus L}} How Far Away Is the Moon From Earth? Change 240,000 mi to km: 1.609 * 240000 = 386,160 km The method took advantage of the fact that the Moon is actually closest to an observer when it is at its highest point in the sky, compared to when it is on the horizon. There are eight moon phases. Lunar distance (LD or $${\textstyle \Delta _{\oplus L}}$$), also called Earth–Moon distance, Earth–Moon characteristic distance, or distance to the Moon, is a unit of measure in astronomy. And at its most distant point (called apogee) the Moon gets to a distance of 406,696 km (252,088 miles). Careful measurements from 1905 to 1910 measured the angle of elevation at the moment when a specific lunar crater (Mösting A) crossed the local meridian, from stations at Greenwich and at Cape of Good Hope, which share nearly the same longitude. That means 30 Earth-sized planets could fit in between Earth and the Moon. The mean semi-major axis has a value of 384,402 km (238,856 mi). This phenomenon is known as the Moon illusion. Fossil studies of mollusk shells from the Campanian era (80 million years ago) show that there were 372 days (of 23 h 33 min) per year during that time, which implies that the lunar distance was about 60.05 R⊕ (383,000 km or 238,000 mi). Find the distance from earth to the moon and sun to moon. The distance varies because the moon travels around Earth in an elliptical orbit. This is the average distance since the orbit of the Moon is ecliptic, and the distance from the Earth to the Moon varies. Please support this site by disabling or whitelisting the Adblock for "justintools.com". It is also known that as the time passes, the Moon moves away from the Earth. Scientists found out that the average distance from the Earth to the Moon is 384,400 km or about 238,855 miles. For increased accuracy, certain adjustments must be made, such as adjusting the measured angle to account for refraction and distortion of light passing through the atmosphere. Don't forget to … Size and Distance. This can give you an idea of how they compare. Laser measurements show that the average lunar distance is increasing, which implies that the Moon was closer in the past, and that Earth's days were shorter. Find My Location: IP address, city, latitude & longitude. Although the Moon itself is not a light source, it has always been the second brightest object in the sky, after the Sun. During the Apollo missions in 1969, astronauts placed retroreflectors on the surface of the Moon for the purpose of refining the accuracy of this technique. The moon's distance varies within its orbit. Before accurate mechanical chronometers, the synchronization event was typically a lunar eclipse, or the moment when the Moon crossed the meridian (if the observers shared the same longitude). Early attempts to measure the distance to the Moon exploited observations of a lunar eclipse combined with knowledge of Earth's radius and an understanding that the Sun is much further than the Moon. ; Press the Play button at the bottom of the chart to make time move in fast forward mode. It is also known that as the time passes, the Moon moves away from the Earth. The distance that the Moon is from the Earth varies throughout the year. Follow-on experiments lasting one month produced a mean value of 384402±1.2 km (238,856 ± 0.75 mi),[36] which was the most accurate measurement of the lunar distance at the time. From the measurements, the distance was calculated with an uncertainty of 1.25 km (0.777 mi).[35]. Tennis ball 3. express your answer in mies per hour Answer by hovuquocan1997(83) (Show Source): As long as people have looked at the moon, they have wondered how far away it is from Earth. assuming that the orbit of the moon around earth is circular and that 1 revolution takes 27.3 days, find the linear speed of the moon. In fact the true distance between the Moon and Earth can change as quickly as 75 meters per second,[2] or more than 1,000 km (620 mi) in just 6 hours, due to its non-circular orbit. An experiment which measured the round-trip time of flight of laser pulses reflected directly off the surface of the Moon was performed in 1962, by a team from Massachusetts Institute of Technology, and a Soviet team at the Crimean Astrophysical Observatory.[37]. The Moon is farther away from Earth than most people realize. A more ambitious project called the "Aristarchus Campaign" was conducted during the lunar eclipse of 15 April 2014. The distance between the Earth and the Sun is so great that the light from the Sun takes about eight minutes to hit the Earth’s surface, traveling at 186,000 miles per second. This section is intended to illustrate some of the historically significant or otherwise interesting methods of determining the lunar distance, and is not intended to be an exhaustive or all-encompassing list. But if you took an average distance, the moon is approximately 238,855 miles (384,400 km). Scientists found out that the average distance from the Earth to the Moon is 384,400 km or about 238,855 miles. The Moon is spiraling away from the Earth at an average rate of 3.8 cm (1.5 in) per year, as detected by the Lunar Laser Ranging Experiment.[8][9][10]. With a radius of 1,079.6 miles (1,737.5 kilometers), the Moon is less than a third the width of Earth. This site is my passion, and I regularly adding new tools/apps. This is the average distance since the orbit of the Moon is ecliptic, and the distance from the Earth to the Moon varies. (Intermediate) - Curious About Astronomy? In other words, the distance to the Moon is 864,000 divided by 3.5, or around 247,000 miles. The actual distance varies over the course of the orbit of the Moon, from 356,500 km (221,500 mi) at the perigee to 406,700 km (252,700 mi) at apogee, resulting in a differential range of 50,200 km (31,200 mi).[2]. [16] There are other effects that also influence the lunar distance. By measuring the parallax between the Moon and the chosen background star, the lunar distance was calculated.[38]. The Moon’s elliptical orbit with the distances at apogee and perigee. The average distance between the Earth and the Moon is 384 400 km (238 855 miles). However, due to its elliptical orbit with varying eccentricity, the instantaneous distance varies with monthly periodicity. Other forces responsible for minute perturbations are: gravitational attraction to other planets in the solar system and to asteroids; tidal forces; and relativistic effects. It is predicted that the lunar distance will continue to increase until (in theory) the Earth and Moon become tidally locked, as are Pluto and Charon. The distance from Earth to the moon is about {eq}22^4 {/eq} miles. The table below lists the distance of each planet from the Sun in AU. Lunar distance is commonly used to express the distance to near-Earth object encounters. But before you go thinking that this is the final answer, you need to consider a few things.