Slashdot Mirror
Worldwide Focus On Going To The Moon
MojoT writes "There's an interesting piece over at Space.com regarding the current renewed interest in returning to the Moon. Quoting: 'Earth's scuffed up and trampled Moon is once again targeted for high- tech visitors. Robotic spacecraft from several nations, as well as NASA and the U.S. Department of Defense, will be first to chalk up lunar return mileage.'"
Which raises an interesting question.. when will countries start claiming territory on the moon?
The U.N. has specifically declared space to be "the province of all Mankind". Since all of the space capable nations are members of the U.N., my answer would be not anytime soon.
I've dirtied my hands writing poetry, for the sake of seduction; that is, for the sake of a useful cause. --Dostoevsky
The Van Allen belts are only a danger if you stay in them for a long time. IIRC the Apollo astronauts were only in the belts for about 2 hours, not nearly enough to have any detrimental effect. If you sat in them for two weeks you'd have problems.
:-)
It's like getting X-rays - you're fine if done in moderation.
This webpage from Cal Tech shows various relevant calculations of Van Allen radiation that suggest the dosage during the 1.5 hours of passage of the belts would be about 2 rem, about 100x less than an often-fatal dose.
--LP
Radiation causes damage to an organism's cells based on the probability of it interacting with molecules in your body. You can get the same risk of negative effects by sitting in heavy radiation for a short period of time, or by sitting in light radation for a very long period of time.
(Which is you always encounter a seemingly contradictory situation when you have X-rays done at a doctor's office: the medical personnel always tell you that the amount of radiation you'll be recieving is not enough to hurt you... then they put a lead shield over your nuts and walk into the next room before they turn the thing on! The amount of radiation being sent IS very small, and so it has a very small chance of hurting you, but if they stayed in the room and were exposed to it multiple times a day every day for years in a row, it would be the same as recieving a heavy dose once or twice. They cover your gonads because although the risk is very small, it's not zero, and a mutation in your nuts is far more catastrophic to your ability to survive and pass on your genes than it would be in any other random cell in your body.)
The radiation in the Van Allen belts is more than a human body would normally experience on Earth. So I guess if you were for some reason spacewalking out there all day, you'd not be feeling too well. However, the astronauts are never just sitting around there playing zero-G frisbee with each other. They are always travelling thru it at very fast speeds (and so are not exposed for very long), and they are also riding in a SPACESHIP, which blocks some of it out. Some will still get thru, but not enough to be sterlizing anything. I've seen some people do calculations and figure that at the speed the Apollo astronauts were travelling through it, they would absorb about 1-2 rems. You don't start seeing symptoms of radiation poisoning until you get near 25 rems.
If you rode a subway thru the Van Allen belts for 45 mins every day for years on your commute to work, then yeah, you're going to see some premature cancer popping up, regardless of whether or not the bum next to you is blowing secondhand smoke in your face. But astronauts travelling thru it for about 2 hours once up and once back are not going to be turned into microwave popcorn or anything.
As simply wrong. The Soviet Union did very poorly by its own citizens, but its military posture was always defensive, and even conservative US military analysts will largely agree. Taking over the world was not their goal. Extending their "sphere of influence," on the other hand, was - as it is that of the US.
People have already made counter arguments for each of the shows claims.
here
Fact: the materials to build the space elevator don't exist yet. Carbon nanotube composites might, but nobody has yet demonstrated one, let alone demonstrated that the material can be produced in quantity and at a realistic cost. Until they are, and the exact properties of the proposed material are known, estimates of the cost and timeframe of a space elevator is just speculating.
Until those nanotube composites become a lot closer to availability, abandoning conventional exploration on the grounds that a space elevator might at some uncertain future time make space travel much cheaper is silly.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
lasers are bounced off of the reflectors left by the astronauts by independent, civilian laboratories on a regular basis. now shut the fuck up.
think again [warning: this link points to a huge PowerPoint file].
Got time? Spend some of it coding or testing
Funny how the article doesn't even mention the only company to yet have actually got permission from the US Government to launch to the moon, TransOrbital Inc.
:v)
Vik
A short haul? The longest part of the trip is the first couple minutes during take-off and the last couple before landing. By the time you're in a Lunar insertion orbit you're still in orbit around the Earth and used up most of your fuel, the trip to the moon is a couples days of coasting before being caught by its gravity.
The ISS is expensive as hell because the Shuttle is launching it with its $10,000 per pound launch cost. Expendible rockets could launch systems for a much lower price tag per pound. According to NASA a person consumes 2.2 pounds of oxygen, 1.3 pounds of food, and nearly 6 pounds of water each day. Water and oxygen are relatively easy to stick in a closed loop system, on Salyut 6 water was extracted from cosmonauts exhalations and reclaimed. The system boasted about a 50% return rate and dropped the weight of stored water on the station from 10.2 to tons to only 2 tons. Mir had a closed loop air filtration system and there is an abundance of sunlight on the Moon for two weeks, that is plenty of time to generate a slew of oxygen. That isn't even to mention all the oxygen stored in the ilmenite in Lunar basalt ejectae.
A Lunar research station would cost little more if any than the in my opinion failed ISS. Observatories on the moon don't need to be reboosted after a period of time because their orbits have degraded. Systems mostly buried under lunar soil are also going to last longer than equipment exposed to space. Small robots with little more capability than the Mars Pathfinder rover can set up telescopes and antenna dishes. Hell a lander for a human group could double as a housing or mounting for a telescope. After you've left and gone the telescope pops out of its housing and gets to work. Some optical cable laid between telescopes could net you an interferometer with of decent gathering power because there isn't a hundred miles of radiation absorbing atmosphere above it.
The ISS is expensive and is not as useful as it was originally envisioned to be. Nor is it any cheaper than it is envisioned to be. For all the PR attached to the damn thing it is really taking money away from much more worthwhile NASA projects. The Freedom project should have never been turned into the ISS. The US is footed most of the tab and not getting much in return for it. NASA shouldn't be wasting billions of dollars out of its miniscule and insulting budget to merely maintain people in space. Have them do something cool besides float around.
I'm a loner Dottie, a Rebel.
Bzzzt. Thank you for playing. Energia (which isn't even being built anymore) didn't even have the throw-weight of an Saturn V, and it's the biggest rocket the Russians have ever successfully launched. Compared to the Saturn, it's an Estes kit. It can't put the mass into LEO that the Saturn put into Translunar orbit.
Energia: LEO Payload: 34,000 kg. to: 200 km Orbit. Liftoff Thrust: 1,633,160 kgf. Total Mass: 1,022,800 kg. Core Diameter: 7.7 m. Total Length: 24.0 m. Flyaway Unit Cost $: 80.00 million. in 1985 unit dollars.
Saturn V: LEO Payload: 118,000 kg. to: 185 km Orbit. at: 28.0 degrees. Payload: 47,000 kg. to a: Translunar trajectory. Liftoff Thrust: 3,440,310 kgf. Total Mass: 3,038,500 kg. Core Diameter: 10.1 m. Total Length: 102.0 m. Development Cost $: 7,439.60 million. in 1966 average dollars. Launch Price $: 431.00 million. in 1967 price dollars.
Source
You can only drink 30 or 40 glasses of beer a day, no matter how rich you are.
-- Colonel Adolphus Busch