2
$\begingroup$

The two current answers to Has anyone in space seen or photographed a simple laser pointer from Earth? both describe small, low power lasers from Earth aimed towards the ISS in LEO.

Here I'd like to ask about human sightings or photos of an Earth-fired laser from beyond LEO

Question: Has anyone in space beyond LEO seen or has anything photographed a non-pointer laser from Earth?

There certainly has been laser-based optical communications beyond LEO but we'll either need a quoted testimonial from a human ("I saw it!") or an example of an image itself.

$\endgroup$

1 Answer 1

6
$\begingroup$

Check out Surveyor 7. "Laser beams from Earth are successfully detected by the craft's television camera in a special test of laser-pointing techniques."

See also:

This photograph was taken by the on-board TV camera on the Surveyor VII spacecraft on January 21, 1968. ...two laser beams are to the left center. The left hand point is the laser from Table
Mountain and the other is from the Kitt Peak facility. The beams were equivilant to a first magnitude
star, as seen from the lunar surface.

This photograph was taken by the on-board TV camera on the Surveyor VII spacecraft on January 21, 1968. The TV signals were sent back to JPL's Pasadena facility via the Goldstone Tracking Station near Barstow, California. The TV images were saved to a video recorder, and later transferred, frame-by- frame to 70mm black and white film. This frame is only one of the thousands of slow-scan images that were returned and saved. The TV scan lines on the original image interfered with the scanner processed to make the above image.

The image is of the crescent Earth (not Moon) as seen on the right, a small black artifact is seen just above center, and the two laser beams are to the left center. The left hand point is the laser from Table Mountain and the other is from the Kitt Peak facility. The beams were equivalent to a first magnitude star, as seen from the lunar surface.

During much of the TV imaging, Table Mountain's telescope was scanned from left to right to determine the size or width of the laser beam. The laser beam left the telescope as a 24-inch diameter collimated beam of light. As it passed through the Earth's atmosphere, the beam was apparently dispersed, and thus causing a larger sized image as seen from the moon.

Table Mountain Observatory, operated by the Jet Propulsion Laboratory (JPL), is located just west of the town of Wrightwood, California at an elevation of 7500 feet.

$\endgroup$
2

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.