Lunar Lasers

Two different articles about building lasers (well, lasers and a maser perhaps) on the moon. Reuters has a story about a potential lunar power plant, creating electricity with solar panels and beaming it to Earth with microwaves. Space.com has a piece about building a sort of super-sized Star Wars program on the Moon, giant lasers set up to blast incoming space debris and not, of course, anyone here on Earth.

Comments

This is a weapon of massless destruction

[KarmaBlackballed]

The power sent as microwaves must be focused into some reasonable area unless they propose having antennas nearly the size of the moon on earth.

1. How will they focus the beam on receptor antenas?

2. How will they keep airplanes from flying across the beams?

3. Will they coordinate with satellite operators so they can avoid the beam too?

The only way for this not to harm you would be for it not to strike you. Early radar technicians learned about microwave cooking standing in front of such beams

Re:This is a weapon of massless destruction

[Waffle Iron]

The article talks about a beam that has 20% of the sun's power density, i.e., less than 150 W per square meter.

If this is so, then why bother with this system at all? A direct solar collector on earth could generate nearly as much energy per square meter as the receiver antenna. Even if you needed 5X more solar collector area on earth as microwave receivers due to efficiency, night and clouds, you'd still come out ahead because wouldn't need to pay interest on a trillion dollar lunar infrastructure.

If they don't bite, lower the price...

[ObligatoryUserName]

The solar power plant on the moon idea has been around for quite a while, but the last time I heard of it, the estimated cost was more than a trillion dollars (I seem to recall it being closer to 2 trillion dollars). Even though it cost so much, the scientist (I can't remember who it was, so it might be the same guy) said it could make back all its costs in under a year by selling power to everyone on Earth at a rate that was lower than what we would pay otherwise.

What I'm curious to know is has the cost of space missions gone down so much since then that it can now be done for the $59 billion listed in the article, rather than the >$1 trillion number cited a number of years ago, or is there some new trick (sure sounds the same), or is this guy just making up a lower number so that people will actually listen to him? Anyone out there heard of this Prof. Criswell before? I'd really like to believe that this is a viable option.

Watch Your Eyes

[Myriad]

It seems inevitable that whenever there is a story regarding lasers we get to see all sorts of silly posts about blasting people with laser.

Even antimissle lasers have a long way to go. Between power requirements, beam handling, divergence, and atmospheric interference, lasers do not make great destructive weapons.

However, they would be damned good for some nasty tricks like blinding the enemy army (or, unfortunately, civilians).

Take this scenario: a bomber/cargo style aircraft has been outfitted with a large infrared laser (similar things have been done). Fly said aircraft over the people you wish to 'zap'. Release some fireworks or other attention getting devices and when the crowd looks up turn on and start scanning the laser.

Since the laser is infrared nobody would know they are being exposed to blinding levels of light, nor would the blink/aversion reaction take place. By the time you noticed anything the permanent damage has been done. Scary huh?

Another scenario under serious consideration by police (at least here in Canada, I've participated in meetings on the subject) is the use of lasers against commercial aircraft. The idea isn't to shoot down the aircraft, but to scan at temporarily blind the pilot during final night approaches. The effect is like someone flashing a camera flash in your face when your in a dark room.

As the few moments prior to landing are the most critical, distracting and flash blinding the pilot could easily lead to the plane crashing.

Worse, new solid state lasers are available in the 3watt (plenty of power to cause permanent blindness) range and can be powered off a car with an inverter. Simply park at the end of a convenient runway at night, plug 'er in and away you go. Ok, so it's not quite that easy, but the concept is...

Doesn't that all just scare you a bit more than some silly death ray?

Note: after saying all that I want to point out that I do not support the insane regulations placed against the use of lasers in the United States by the CDRH. It's totally ridiculous and overzealous.

1982 World's Fair proposed this

[GMontag]

I have mentioned this in the other, almost identical, articles on beaming power to earth from space.

There was a proposal for the 1982 Knoxville World's Fair to do this from a satellite and have the microwave beam land on a mesh reciever.

The pesky problem had something to do with safety of birds passing through the beam, since they do not read Notices to Airmen and have no concept of "no fly zones".

The problem is compounded by basing this on the moon, since it is not geocincronious and the beam would have to continuously move to stay on target. It can only be on one target about 12 hrs/day or so too. (Yes, they CAN generate through the whole lunar cycle since the collectors can be placed all around the moon and only the transmitter has to be on the near side)

We already have antennas

[KarmaBlackballed]

you simply stretch out a wire between two insulated poles, and the power just flows

You bring up an important point: powerlines and phone lines already cover the globe. They will pick up the power too. This may not be a good thing.

Problems

[saider]

Has anyone built a 100% automated large scale power plant? Even here on Earth, such a task is daunting. Saying that it can be easily done on the moon, and done cost effectively is like saying that I could build cheaper cars on the moon because my machinery will only have to cope with 1/6th of the gravity.

"But satellites and the space shuttle use solar power all the time." They also have either a 5-10 year lifespan or are serviced regularly. The article said that it could be profitable in 5 years. So when it finally becomes profitable, many of its components will be nearing the end of their lifespan. Then you have to chunk down some more money to build a replacement.

Nevermind that there will still need to be multiple ground stations in remote areas to catch the radiation. The moon is not geosynchronous. Build a station at the poles you say? There goes your costs again. Also, say what you want about safety, nobody will want to live near these things. And they will have to be in different countries which brings politics into the mix.

This is pie-in-the-sky dreaming. If you ask me, I think the money is better spent designing and running a good nuclear power plant or for some fusion research.

Re:Who owns the moon?

[overunderunderdone]

Who says the US has the right (or lack thereof) to put anything like this on the moon?

The "lack thereof" in brackets answers the main question. Whoever gets there and does it will have the "right" to go there and do it. I imagine the way we deal with completely unclaimed territory is still found under the "finders keepers losers weepers" clause of international law. I imagine something along the lines of an explorer planting his flag in the dirt and declaring "I claim this bit of rock for $sponsoring_country" which come to think of it the USA has already done on the moon.