a reply to: Hyperboles
Mythbusters made an episode where they show how lasers are bounced off retroreflectors on the moon, which is a source of reflected light in the sky
which you can see. Whether photons are reflected back from the moon or not depends on where exactly on the moon you aim your laser. If aimed at a
retroreflector, the reflected photons provide the distance to the moon and help us determine how fast the moon is moving away from the Earth by making
repeated measurements over time.
The video explains how an estimated 200,000,000,000,000,000 photons are fired at the moon. When aimed at the lunar highlands, they get no photons
back. Then they aim at the retroreflector left on the moon by Apollo 15 and 1-3 photons returned to their detector, so even with the retroreflector,
it's a low return rate.
I would guess they more or less assume a vacuum between Earth and the moon, though I suppose the speed through Earth's atmosphere might be a hair
lower, but I wouldn't expect that to be much of a correction if they make it at all. The observatory they use like many observatories is on a
mountain, and if you wanted to fly a plane much higher the plane would need to be pressurized because the atmosphere is already thinner at mountain
I don't know what other light sources you have in mind, but the moon is the closest natural object and that doesn't even work without the
If you aim a laser at an object flying through Earth's atmosphere, I think in many places that's a crime and folks in the US can now get up to $10,000
for turning in people who do it, so I wouldn't recommend it, but too many idiots do it, with some thinking they are signaling UFOs or some such crazy
nonsense. Some get tracked down and arrested and spend years in prison.
Whether the intent is malicious or not, with President Barack Obama signed a law in 2012 making it a federal crime to aim a laser pointer at an
aircraft. Two years later, the FBI launched a new public awareness campaign on the issue and authorized rewards up to $10,000 to track down anyone
That's happened a few times, including a 2012 guilty plea from a 49-year-old Orlando man who court documents indicate aimed laser beams at passenger
aircraft leaving that central Florida city's airport at least 23 times. His action caused pilots to take evasive maneuvers during takeoff and placed
the aircraft in danger during a critical time in flight, officials said.
Adam Gardenhire, 19, got 30 months in federal prison for shining a laser pointer at a plane and police helicopter in 2013. The pilot of a corporate
jet was hit in the eye multiple times and had vision problems through the next day, according to court documents.
The next year, a 33-year-old South Carolina man was sentenced to 37 months for aiming a laser pointer "at two news helicopters as they were flying to
cover an accident on the interstate," the FBI said.
edit on 2018316 by Arbitrageur because: clarification
Hi. Time for an aetherial update, and also, a question.
Aetherial Update. I now believe I have the aetherial affects understood that lead to the Lorentz force equation. Note however that I've thought I was
close for months now, and I thought I had the affects understood several times before, and each time in the past things blew up as I found a flaw
shortly after I tried to write up the derivation. This time I'm about half-way into the derivation and no blow-up yet. It might still fail, but it is
looking promising. If all goes well I hope to have this all written up and checked by early April. I'll of course let you know either way - whether it
works out or if it blows up yet again.
Question. Does anyone know if the general relativity equations could be based on a warping of an aether instead of a warping of space and time? I
realize this might be something I need to work out myself, but perhaps someone has already done this. As an analogy, the Lorentz transformations can
be understood as coming from an alteration of measuring devices (meter sticks and clocks) rather than an alteration of space and time.
In 1887 adaptive optics correction was probably more cost effective than using a space based telescope.
I imagine the shell panels of moon probes from the Luna program were reflective.
The Germans were bouncing microwaves off the moon back in the 1930's.
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