The last instrument being brought to the surface is a laser retroreflector array made by Italy’s Laboratori Nazionali di Frascati. That array requires no power from the lander and will remain usable so long as a line of sight to Earth is possible due to it consisting of a set of mirrors designed to bounce light back to our planet for high-precision measurements of distance.
I have to ask, has anyone here ever tried hitting one of these retroreflectors on the moon with a laser? How powerful of a laser do you need to see the reflection with your naked eye?
It would be awfully cool to get that to work. It would also be cool to be able to "see" the speed of light. As you could flash the laser and see it blink in response 2.5 seconds later.
Edit: I decided to look it up myself and it turns out, no there's simply no sufficiently powerful laser in the entire world to allow you to see the reflection with the naked eye. Detection generally requires a very powerful laser, a very powerful telescope and very powerful detection equipment to detect the 1 or 2 photons that actually reflect back. Too bad :-(
I thought they were mainly for Lunar orbiters to target. If you can figure out an Earth based one as a hobbyist I'd expect a van outside pretty soon, lol.
2 Comments
Cocodapuf@lemmy.world · 4 pts · 34d
Ok, so I was reading this part of the article:
I have to ask, has anyone here ever tried hitting one of these retroreflectors on the moon with a laser? How powerful of a laser do you need to see the reflection with your naked eye?
It would be awfully cool to get that to work. It would also be cool to be able to "see" the speed of light. As you could flash the laser and see it blink in response 2.5 seconds later.
Edit: I decided to look it up myself and it turns out, no there's simply no sufficiently powerful laser in the entire world to allow you to see the reflection with the naked eye. Detection generally requires a very powerful laser, a very powerful telescope and very powerful detection equipment to detect the 1 or 2 photons that actually reflect back. Too bad :-(
burble@lemmy.dbzer0.com · 1 pts · 34d
I thought they were mainly for Lunar orbiters to target. If you can figure out an Earth based one as a hobbyist I'd expect a van outside pretty soon, lol.