Homework Help

How Far Is The Moon From The Earth?

enotes's profile pic

Posted via web

dislike 14 like

How Far Is The Moon From The Earth?

61 Answers | Add Yours

mrbakertheteacher's profile pic

Posted (Answer #1)

dislike 14 like

Astronomers during the Apollo missions placed mirrors on the surface of the earth so that scientists can fire a laser beam to the moon, wait for the beam to reflect off of the mirrors and return to earth. Because they know how fast a laser beam travels, they can calculate the distance within centimeters.  They found that when the moon is closest to earth it is 363,104 km (225632 mi) away. When it is at it's furthest point away it is 405,696 km (252,099 mi) away. The average distance away is 384,393 km (238,854 mi) away.

 

 

fact-finder's profile pic

Posted (Answer #2)

dislike 11 like

Since the moon's orbit is elliptical (oval-shaped), its distance varies from about 221,463 miles (356,334 kilometers) at perigee (closest approach to Earth) to 251,968 miles (405,503 kilometers) at apogee (farthest point). The average distance from the moon to the Earth is 238,857 miles (384,392 kilometers).

Sources: McGraw-Hill Encyclopedia of Science and Technology 7th ed., vol. 5, p. 470; The Universal Almanac 1992, p. 16.

melissaivanarampersad's profile pic

Posted (Answer #5)

dislike 11 like

Are you wondering how far is the Moon from Earth? Well, the exact number is an average of 384,399 km, or 238,854 miles.

 

         

This number is an average because the Moon takes an elliptical orbit around the Earth. Sometimes it’s closer than this average number, and other times it’s more distant. At its closest point, called perihelion, the Moon measures 363,104 km from the Earth. And then at the most distant point of its orbit, known as aphelion, the Moon is 405,696 km from Earth. This is a big difference: 42,592 km.

Because of this huge different in difference, the size and brightness of the Moon can change dramatically when the full Moon matches up with a close Moon. It can be 15% larger and 30% brighter than an average Moon.

You might be surprised to know that astronomers have actually measured how far the moon is from Earth to within a few centimeters. They’re able to do this because the Apollo astronauts left small reflective mirrors on the surface of the Moon during their last mission. Astronomers on Earth fire a laser pulse at the Moon and measure how long it takes to hit the Moon, bounce off the reflectors and return to Earth. By knowing the speed of light, and timing the return journey of the light pulse, they’re able to calculate the distance to the Moon with incredible accuracy.

ajprincess's profile pic

Posted (Answer #4)

dislike 11 like

It is approximately 384,405 km away.................................

isks149's profile pic

Posted (Answer #3)

dislike 10 like

Well, the exact number is an average of 384399 km, or 238854 miles.

leandraberchman's profile pic

Posted (Answer #6)

dislike 10 like

average distance of 3,85,000 km

anveshanushka's profile pic

Posted (Answer #7)

dislike 10 like

earth- moon distance -384,405 km   (center to centre )

crazynitin1998's profile pic

Posted (Answer #8)

dislike 10 like

when the moon is closest to earth it is 363,104 km away. When it is at it's furthest point away it is 405,696 km  away. The average distance away is 384,405 km  away.

twinkysweet30's profile pic

Posted (Answer #11)

dislike 10 like

average of 384399 km, or 238854 miles.

patelmilia98's profile pic

Posted (Answer #12)

dislike 10 like

384399 km or 238854 miles

academy633's profile pic

Posted (Answer #13)

dislike 10 like

What should be noted is that the moon is gradually, very gradually, moving away from the earth.  Tidal friction is not only slowing the earth's rotation, but is draining energy from the moon's motion.See http://curious.astro.cornell.edu/question.php?number=124  for a complete explanation.

Also, did you know that the earth-moon system is a double planet, and the only one in our solar system.  The moon's orbit around the sun is always concave relative to the sun, unlike every other planetary satellite in the solar system.  The moon's mass is much greater relative to the earth than the same ratio of other satellites to their solar system planets.  And the paths of all other satellites exhibit retrograde motion, but our moon doesnot!   We are living on a double planet! 

melonsmasher's profile pic

Posted (Answer #9)

dislike 9 like

The moon is 384,403 kilometres away from the earth !!!!!!

ashleyblowes's profile pic

Posted (Answer #10)

dislike 9 like

earth- moon distance -384,405 km   (center to centre )

Sources:

ayy-dee's profile pic

Posted (Answer #16)

dislike 9 like

±384, 402 km

lnj100's profile pic

Posted (Answer #17)

dislike 9 like
The distance varies somewhat, during the course of a month and also during the course of a year.

It averages out to about 93 million miles.

The moon's average distance from the sun is the same as the earth's average distance from the sun. When you think about it... the moon orbits around the earth, so it's closer to the sun half the time, and farther from the sun half the time... averaging out to the same distance from the sun as the earth is.

In any case, the moon averages 238,000 miles from the earth, which is less than 1/4 million, and that doesn't make much difference compared to the 93 million average between the earth and the sun... less than 1/4 of 1 percent.
troubleshooter's profile pic

Posted (Answer #18)

dislike 9 like

The distance to the Moon is actually slowly increasing!

Over millennia, the gravitational pull of the tides are pulling on the Moon and transferring energy.  The Earth is loosing energy, and the Moon is gaining energy!  This is slowing the rotation of the Earth, and speeding up the Moon.  This causes the Moon to move away from the Earth, and our days to become longer!

See:
http://en.wikipedia.org/wiki/Orbit_of_the_Moon#Tidal_evolution

The distance to the Moon increases by 38 mm per year[1] and our days are increasing about 15 microseconds every year[1]. (This is not a fixed rate and will change in the far future as the Earth slows and the Moon recedes).

[1]
http://en.wikipedia.org/wiki/Moon#Tidal_effects

Mr KL

beancounters's profile pic

Posted (Answer #19)

dislike 8 like

About 240,000 miles.

akshaybhaskar's profile pic

Posted (Answer #20)

dislike 8 like

Earth - moon distance is somewhere around 384,405 km to 384,500 km

 

bishalnaskar's profile pic

Posted (Answer #21)

dislike 8 like

The distance between the Moon and the Earth varies from around 3,56,400 km to 4,06,700 km!!

vgopaul12's profile pic

Posted (Answer #23)

dislike 8 like

The average distance away is 384,405 km away.

bookofshadows's profile pic

Posted (Answer #24)

dislike 8 like

384400 km is the distance from the moon to the earth

crazynitin998's profile pic

Posted (Answer #25)

dislike 8 like

when the moon is closest to earth it is 363,104 km away. When it is at it's furthest point away it is 405,696 km  away. The average distance away is 384,405 km  away

pororohandy's profile pic

Posted (Answer #26)

dislike 8 like

The moon is 384,403 kilometres away from the earth !!!!!!

inneedofhelp3550's profile pic

Posted (Answer #27)

dislike 8 like

They found that when the moon is closest to earth it is 363,104 km (225632 mi) away. When it is at it's furthest point away it is 405,696 km (252,099 mi) away. The average distance away is 384,393 km (238,854 mi) away. Or alternitivly, very far away.

ayy-dee's profile pic

Posted (Answer #28)

dislike 7 like

±384, 402 km

zopalwie's profile pic

Posted (Answer #30)

dislike 7 like

average of 384,399 km, or 238,854 miles.

astrosonu's profile pic

Posted (Answer #31)

dislike 7 like

384400 km

loraaa's profile pic

Posted (Answer #14)

dislike 6 like
384,500 km.
khansaqib's profile pic

Posted (Answer #35)

dislike 6 like

moon is 380000000metres away from earth.

myfavouritehero's profile pic

Posted (Answer #39)

dislike 6 like

Moon is at a distance of about three lakh and eighty five thousand (385,000)kilometers from Earth.

ayy-dee's profile pic

Posted (Answer #40)

dislike 6 like

±384, 402 km

pororohandy's profile pic

Posted (Answer #42)

dislike 6 like

The moon is 384,403 kilometres away from the earth !!!!!! The moon's orbit is not a perfect circle, it is an ellipse; So the distance isn't constant ... there is a minimum and a maximum. The distance fluctuates between 363,104 kilometers and 405,696 kilometers (225,622 to 252,088 miles) due to the eccentricity of the Moon's orbit

miami-heat-6's profile pic

Posted (Answer #29)

dislike 6 like

It is around about 350,000 kilometres away.

thisuserhasmadeabadusername's profile pic

Posted (Answer #38)

dislike 5 like

About 250,000 miles---similar to the amount on my parents' old minivan!

sidgupta's profile pic

Posted (Answer #32)

dislike 4 like

It is approximately 300,000 km from the earth

suretowin's profile pic

Posted (Answer #47)

dislike 4 like

THE MOON IS  " 380000000 metres" AWAY FROM EARTH !

 

vgopaul12's profile pic

Posted (Answer #36)

dislike 4 like

the exact number is an average of 384399 km

briceyboi's profile pic

Posted (Answer #37)

dislike 4 like

It's around 360,000km away from Earth or 290,000 miles away. Basically it's far away

adarshanurag's profile pic

Posted (Answer #52)

dislike 4 like

the distance is 3,84,400 km.

anzheng's profile pic

Posted (Answer #53)

dislike 4 like

The moon is 238,900 miles (384,400 km) from the Earth!

Yojana_Thapa's profile pic

Posted (Answer #54)

dislike 4 like

384399 km or 238,900 miles

parama9000's profile pic

Posted (Answer #55)

dislike 4 like

384399 km or 238900 miles. There is information on this on Wikipedia

amysor's profile pic

Posted (Answer #56)

dislike 4 like

According to most experts, the Moon is approximately 239,900 miles (384,400 km) away from the earth.

Chantelm's profile pic

Posted (Answer #58)

dislike 4 like
238,900 miles (384,400 km)
laurto's profile pic

Posted (Answer #59)

dislike 4 like

The Moon takes an elliptical path around the Earth, which means that the Earth can get closer and further away. The average distance is 384,403 km. At its closest point, it is only 363,104 km and at its most distant point it is 406,696 km. In other words, it is very, very far but it is sometimes closer and sometimes further than the average. 

Chantelm's profile pic

Posted (Answer #61)

dislike 4 like

384,399 km, or 238,854 miles.

zumba96's profile pic

Posted (Answer #62)

dislike 4 like

The Moon from the Earth is 238,900 miles away which is 384,400 km.

acompanioninthetardis's profile pic

Posted (Answer #63)

dislike 4 like

The moon is 238,900 miles or 384,400 kilometers from the earth. 

Sources:

adasison's profile pic

Posted (Answer #65)

dislike 4 like

The moon is 238,900 miles (384,400 km) away from Earth.

ik9744's profile pic

Posted (Answer #66)

dislike 4 like

384,399 km or 238,900 miles. Pretty far away!

rachellopez's profile pic

Posted (Answer #67)

dislike 4 like

According to NASA, the average distance from Earth to the Moon is 382,500 kilometers. However, the distance may vary because the Moon orbits around the Earth. When the moon is closet to the Earth, which is called perigee, it is about 360,000 kilometers away. When it is furthest away from earth, which is called apogee, the moon is about 405,000 kilometers away.

Sources:

taangerine's profile pic

Posted (Answer #68)

dislike 4 like

The moon is approximately 384,399 km, or 238,854 miles, away from the Earth. 

nisarg's profile pic

Posted (Answer #69)

dislike 4 like

238,900 miles is the average distance but it fluctuates with each month. This motion of earth's only satellite causes the tides to rise and fall on the surface of the earth. The moon also slightly affects the earths orbit. At the furthest it is about 405,000 km away from earth

crystaltu001's profile pic

Posted (Answer #70)

dislike 4 like

The distance from the moon to the earth is 384,400 km which is also equal to, 238,900 miles. But there is a chance the distance can change because the moon orbits around the earth and from different locations it may take a different amount of time to get from the earth to the moon.

karlalicious's profile pic

Posted (Answer #57)

dislike 3 like

How Far Is The Moon From The Earth?

*238,900 miles (384,400 km) Moon, Distance to Earth*

Sources:

arrellbelle's profile pic

Posted (Answer #64)

dislike 3 like

The length from the moon to the earth would approximately be 238,900 miles or 384,400 kilometers.

Jyotsana's profile pic

Posted (Answer #60)

dislike 2 like

The moon is 384,399km or 238,900miles far from the earth.

ahmedrehan's profile pic

Posted (Answer #74)

dislike 2 like

385,500 km

gsenviro's profile pic

Posted (Answer #77)

dislike 1 like

The moon is a satellite of planet Earth. The moon revolves around the Earth in an elliptical orbit, which means that the moon-Earth distance is not constant: it changes depending on the moon's location in the orbit.

After careful measurements, it has been found that at its farthest point in its orbit (apogee), the moon is about 405,000 kilometers away from Earth. In comparison, at the nearest point in its orbit (perigee), the moon is about 360,000 kilometers from the earth. Thus, on average, moon-Earth separation is about 382,500 kilometers.

Before the first lunar mission took place, the distance was calculated by a study of planetary motion or by using a telescope. 

Astronauts then left glass reflectors on the surface of the moon, and very precise distance measurements could be carried out by determining the time it took light to reflect back from these reflectors. 

Sources:

brian-sadie's profile pic

Posted (Answer #78)

dislike 0 like

238,900 miles becuase 29,890×10=238,900 miles and 238,900÷10=29,890. And the reason why I  picked 29,890 miles is I kept counting in tell I found the perfect number for me. Which is 238,900. And I used 10 becuase on a TV show said that the moon was 10 times closer.

brian-sadie's profile pic

Posted (Answer #79)

dislike 0 like

238,900 miles becuase 29,890×10=238,900 miles and 238,900÷10=29,890. And the reason why I  picked 29,890 miles is I kept counting in tell I found the perfect number for me. Which is 29,890. And I used 10 becuase on a TV show said that the moon was 10 times closer.

Join to answer this question

Join a community of thousands of dedicated teachers and students.

Join eNotes