Did lasers find the exact distance from the moon to the earth?

Answer 1

The most precise method is laser ranging.

Lasers are "fired" at the Moon aiming for specific reflectors (retroreflectors) that were positioned there during the Apollo landings. The time taken for the return trip is used to calculate the exact distance.

Answer 2

Equipment needed:

A yardstick or meter stick, tape measure?

A piece of notebook paper

A few minutes of un-obscured Moon

Procedure:

1) You may need to recruit some assistance. Holding the yardstick up to your eye, move the paper along the stick until one of the holes just barely contains the outer rim of the moon. A steady stick may be problematic, so you may want to rest it on a chair, ladder, or other object while the paper is moved. Also, you may need to recruit help as the distance between your eye and the paper may exceed your arm length. Try to be as accurate as possible. Once you've reached the location where the hole just contains the moon, record the distance between your eye and the paper in the spaces below. It would be best if you record the distances initially in metric units, but you can convert later if you don't have metric units printed on your yardstick. Repeat this 3 times to lessen the experimental error. Don't forget your units.

Distance #1: Distance #2: Distance #3:

Now, average your readings. Distanceavg = Davg =

Now, if you used English standard units (inches), convert to metric using 1 inch = 2.54 cm.

Davg (in) * 2.54cm/1 inch =

Next, we need to find the diameter of the hole used. It can be tricky to determine the largest diameter using a ruler, so you'll need to perform this measurement 3 times as well by removing the measuring device and placing it over the hole each time you measure it. Remember, use metric units it you can or just convert using the same method as above for converting the distance.

Diameter #1: Diameter #2: Diameter #3:

Now, average the diameters: Diameteravg = davg =

2) This method uses simple geometry. We now have an estimate on the distance between your eye and the hole, as well as the diameter of the hole. Using similar triangles, and the fact that the

Moon has a diameter of about 3475 km, we can attempt to estimate the distance to the moon. Similar triangles will lead to the following formula:

davg/Davg=Diameter of the moon/x

Solving for x leads to

x=(diameter of the moon)(Davg)/davg

Before you calculate your result, make sure that your average distance and average diameter are in the same units, otherwise you'll need to convert. If your diameter and distance units are the same, then they'll cancel each other and your answer will be in km. Calculate your result in the space here:

Answer 3

Scientists have reflective things on the moon and they shine lasers up at it to measure how far away the moon is. _____________________ Before the Apollo astronauts left the laser reflectors on the Moon, there was RADAR!

Answer 4

1. RADAR.

2. It doesn't matter how large an object is; its distance is directly related to its orbit. Measure the precise time that it takes for the Moon to go around the Earth once, and you can calculate how far away it is.

3. Parallax; measure the position of the Moon against the background stars from two points on opposite sides of the Earth at the same moment. You can calculate the distance from the parallax.

Answer 5

Yes. Scientists had calculated the distance to the Moon many years ago, but there was some measure of error in the precise dimensions of the Moon's orbit. Not by much; we can measure with a stopwatch how long it takes for the Moon to orbit the Earth, and that lets us calculate the distance to the Moon pretty accurately; within a couple of miles, or so.

And the US Air Force routinely calibrated their long-range radars by measuring the distance to the Moon.

But one of the items left on the Moon by the Apollo 11 astronauts was a "corner reflector", which allows scientists to measure the distance to within a few millimeters by shining a laser at the Moon and seeing the bright reflection.

Answer 6

We need a coin and a tape measure.

Tape the coin onto a window pane that you can see the moon through.

Step back until the apparent size of the coin and moon are the same.

Measure the distance from the coin (cm) to your eye and the diameter of the coin (cm).

The moon's diameter is 3474 km

We know the ratio of the moon's distance from your eye to its diameter is the same as the ratio of the coins distance to your eye to its diameter.

Thus, using all distances and measurements in cm):

(Moon's distance)/(Moon's Diameter)=(Coin's distance)/(Coin's diameter)

Rearranging:

Moon's distance = (Moon's diameter)x(Coin's distance)/(Coin's Diameter)

This is the moon's distance in cm so divide by 100,000 to convert it to kilometers

Answer 7

293,000 mi's away

Answer 8

Today we measure the distance with lasers or radar

Answer 9

Because light can not reach as far as a laser.

Answer 10

Basically they start a clock when the laser is turned on, then they stop it when they receive a weak pulse of laser light that has been reflected back to Earth from the moon.