How wide is a laser beam on the moon?

about 6.5 kilometers
At the Moon’s surface, the beam is about 6.5 kilometers (4.0 mi) wide and scientists liken the task of aiming the beam to using a rifle to hit a moving dime 3 kilometers (1.9 mi) away. The reflected light is too weak to see with the human eye.

What diameter spot will it make on the moon?

So we have 380,000 kilometers times 1.4 times 10 to the minus 5 radians and that gives 5.3 kilometers should be the diameter of this spot produced by the laser on the moon.

How wide is a laser beam?

The beam diameter can be defined in several different ways, and for Gaussian beams it is typically described by the 1/e2 width. The 1/e2 width is the distance between the two points on the marginal distribution whose intensities are 1/e2 = 0.135 times the maximum intensity value.

What happens when you point a laser at glass?

When light goes from one material to another, it bends. A laser beam that hits water, glass, or plastic will change direction. If the angle is large enough, all of the light is bounced back, and none of it will go into the air. This also happens with clear plastic, glass, and even Jello.

Are there laser reflectors on the Moon?

Retroreflectors are devices which reflect light back to its source. Five were left at five sites on the Moon by three crews of the Apollo program and two remote landers of the Lunokhod program. Lunar reflectors have enabled precise measurement of the Earth–Moon distance since 1969 using lunar laser ranging.

How do you calculate laser beam area?

In the context of laser-induced damage, one often uses an effective beam area, which is defined as the optical power divided by the maximum intensity, and is considered to be π times the effective beam radius squared.

How is laser beam width calculated?

The American National Standard Z136. 1-2007 for Safe Use of Lasers (p. 6) defines the beam diameter as the distance between diametrically opposed points in that cross-section of a beam where the power per unit area is 1/e (0.368) times that of the peak power per unit area.

How long does it take to bounce a laser off the moon?

about 2.5 seconds
By measuring how long it takes laser light to bounce back — about 2.5 seconds on average — researchers can calculate the distance between Earth laser stations and Moon reflectors down to less than a few millimeters. This is about the thickness of an orange peel.