I always liked the story of the Lunokhod 1 - the first of the two Soviet Lunar Rovers. Both had reflectors for laser ranging, but Lunokhod 1 was carelessly misplaced in the early 1970s. So no more ranging until 2010 when the NASA reconnaissance orbiter found it again. They didn't lose the other one. :)
I think one of the Lunokhods still holds the record for the furthest ever travelled by an extra terrestrial vehicle.
Lunakhod 1 was still responding in 2013 (40 years later) thanks to the NASA LRO (Lunar Reconnaissance Orbiter).
French website, as it was a (secret) collaboration between Russians and the CNES who provided the retroreflector:
https://sciences-techniques.cnes.fr/fr/web/CNES-fr/10757-st-...
It also highlights how few impacts the moon gets these days as any impact near this https://en.wikipedia.org/wiki/Retroreflector would kick up moon dust and have a detrimental effect upon such a reflector.
Which is encouraging for any solar installations upon the moon for the one day, eventual moon base.
According to NASA [0], you are correct. Furthermore:
"It is likely that each side of the Moon has received equal numbers of impacts, but the resurfacing by lava results in fewer craters visible on the near side than the far side, even though the both sides have received the same number of impacts."
The earth looks huge from the moon. The moon’s diameter is 2,158.8 mi where earth’s is 7,917.5 mi, meaning it looks 3.5x as wide and covers 13.5x the area. So more your fist at arms length than your thumb.
In terms of impact gravity and atmosphere extend that somewhat. Though, that’s still not enough to make a meaningful difference.
Alas, that's not how it works. Any video you could show of the laser experiment would also be faked. Even if you were to set them in front of the equipment, that'd be faked too. I often wonder as a thought-experiment what would happen if you bundled them onto a Musk style space tourism rocket and flew them to the moon to see the flag (for a bonus they can look back to see the spherical Earth) and then back, would they even then believe the conspiracy or their lyin' eyes?
(Then I catch myself on and realise it wouldn't even theoretically be worth wasting all that effort and money on someone so determined to be willfully ignorant. We live in a world where schoolkids can send a camera high enough to see the curvature of the Earth, yet we are to believe people who have made the denial of this a core of their identity do not see fit to replicate the experiment?)
<Devil's advocate>No point sending a camera up, the camera manufacturers have tweaked the firmware to create the illusion of curvature.
I _know_ the earth is flat, so I already know that GoPro are in on the conspiracy as well.</Devil's advocate>
Your "throw them on a rocket" idea is the only realistic way to convince them I would imagine. Which gives me an idea, maybe that could be my ticket to the moon
Won't work. The "rocket" is simply an advanced simulator with the ability to simulate zero G with high-def displays. No matter what kind of evidence you provide, they will always provide a (far fetched) counter argument.
Right. And even if they conceded that they were on the moon, they'd argue that the 1969 landing was still fake, with props brought to the moon way later.
Jokes aside, the Moon is rally dark. With an albedo of 0.12, it is one of the darkest major bodies in the Solar system, save for Mercury with an albedo of 0.11.
It isn't as simple as point laser at moon, see light shining back with your own eyes, it requires a big telescope and computers and delicate sensors to detect because the moon and earth are so far apart.
I have long wondered how easy it would be to perform this experiment as an amateur. Powerful lasers are quite cheap now. You could get a telescope (doubling as a beam expander and receiver), and some filters to only allow the laser wavelength to your detector.
Actually very difficult. They use a 30in telescope for these observations and the beam becomes extremely attenuated. The laser 'spot' projected on the moon is roughly 7km across. Only a tiny fraction of the light is reflected back as the reflector is only a few feet across, and is similarly attenuated on the return journey. The return beam is 20km across by the time it hits the Earth.
Due to the extreme attenuation of the final signal the observation takes several hours using highly sensitive equipment, averaging it out to extract meaningful data.
Also see the Apache Point Observatory Lunar Laser-ranging Operation (APOLLO)[0]: "APOLLO measures the round-trip travel time of laser pulses bounced off the lunar retroreflectors[1] to a precision of a few picoseconds, corresponding to about one millimeter of precision in range to the moon."
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[ 2.7 ms ] story [ 84.6 ms ] threadI think one of the Lunokhods still holds the record for the furthest ever travelled by an extra terrestrial vehicle.
[1] https://www.jpl.nasa.gov/news/news.php?feature=4232
Which is encouraging for any solar installations upon the moon for the one day, eventual moon base.
"It is likely that each side of the Moon has received equal numbers of impacts, but the resurfacing by lava results in fewer craters visible on the near side than the far side, even though the both sides have received the same number of impacts."
[0] https://lunarscience.nasa.gov/?question=3318
In terms of impact gravity and atmosphere extend that somewhat. Though, that’s still not enough to make a meaningful difference.
(Then I catch myself on and realise it wouldn't even theoretically be worth wasting all that effort and money on someone so determined to be willfully ignorant. We live in a world where schoolkids can send a camera high enough to see the curvature of the Earth, yet we are to believe people who have made the denial of this a core of their identity do not see fit to replicate the experiment?)
I _know_ the earth is flat, so I already know that GoPro are in on the conspiracy as well.</Devil's advocate>
Your "throw them on a rocket" idea is the only realistic way to convince them I would imagine. Which gives me an idea, maybe that could be my ticket to the moon
I mean, if actual pictures of the landing site from LRO don't convince them: https://airandspace.si.edu/multimedia-gallery/628457main1apo... then a few extra photons returning to the earth won't change their mind. (My personal favorite, in an aesthetic sense, is: https://www.nasa.gov/mission_pages/LRO/news/apollo-15.html)
Due to the extreme attenuation of the final signal the observation takes several hours using highly sensitive equipment, averaging it out to extract meaningful data.
[0] https://www.reddit.com/r/askscience/comments/qw30x/can_an_am...
https://movies.stackexchange.com/questions/24686/is-this-las...
YouTube link (for those that like the show): https://www.youtube.com/watch?v=_v52LFgUq-8
[0]: https://tmurphy.physics.ucsd.edu/apollo/apollo.html
[1]: https://tmurphy.physics.ucsd.edu/apollo/lrrr.html
:)