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Buzz Advocates Lagrange Point Spaceport
thrasymachus writes "Buzz Aldrin has an editorial in the New York Times (free reg req) advocating a spaceport at a Lagrange point between the Earth and the moon over simply more moon missions. He emphasizes the cost and practicality of such a station, as well its potential as a 'bridge to the heavens.'"
It's actually quite a good read but not enough to make me want to register...
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A really interesting article about Lagrange Points can be found here. What I found really fascinating is the fact that it seems like that the earth pulls/pushes dust around space on the earth-moon Lagrange Points L4 and L5.
I never knew what a Lagrange point was. I found that Wikipedia gave the best explanation.
Lagrange Point
Every Super Villan uses Linux.
AKA Libration Points...
For any heavenly body with a satellite in a relatively circular orbit, there are 5 points where gravitational forces and centripetal accelerations cancel each other out. Three fall on a line that connects the two bodies, and the other form a pair of equilateral triangles with the heavenly bodies.
L1 between the two bodies
L2 on the far side of the smaller body
L3 on the far side of the larger body
L4 is the "leading" equilateral point
L5 is the "trailing" equilateral point
L4 and L5 are relatively stable. Putting a station at L1-3 would require more propellant to keep it there, though not an unreasonable amount.
Personally, I'd rather go for a base on the Moon that at a libration point. Sure, it requires more propellant to get to and from there, but its also a permanent fixture, rather than something that would need to be disposed of eventually.
"Open the pod by doors, Hal" > "I'm afraid I can't do that, Dave" sudo "Open the pod bay doors, Hal" > alright
You are correct for all Lagrange points in line with the Moon and the Earth. The L4 and L5 points, however will never need repositioning because they automatically re-center themselves. Unfortunately, L4 and L5 are just as distant as the moon is, and have no indiginous resources.
Always going forward, 'cause we can't find reverse.
The Mars Direct plan contradicts you. Read more.
I met Zubrin once. He's a hyper-smart guy, and he's got the right plan. Why are we jacking around in LEO?
Why yes, I AM a rocket scientist!
"Taxes pay for bad things, taxes pay for good things. I oppose the former and support the latter. Too many people are patriotic right up until you ask them to put their money where their mouth is."
awwwwww, how nice... but insightful?
I dont have a problem paying for taxes either. But what should the tax rate be? (%100 = communism, btw). and what should those taxes go towards? right now I think taxes are high enough. the founders of this country were considering putting a cap at 8% for federal taxes, but didn't, because they thought it would never get that high anyways. oops.
when you put money into the hands of the people that create it in the first place, they usually make the best spending decisions.
if rates are very high and you cut them, here is what happens: lower taxes = better economy, cause people have more money to spend on goods and services = more jobs = MORE TAX REVENUE. More taxpayers and more tax income, because of more jobs and better paying jobs).
That is not true if the tax rate is already very low, but it really isnt in our case, compared to the history of the US.
again, I have no problem paying taxes, but look at it logically instead of emotionally. should taxes ALWAYS be higher? are tax cuts ALWAYS bad? if you ALWAYS raise taxes and NEVER cut taxes, sooner or later you will have communism, which is basically a 100% tax rate. and we have seen how that works out... The POOREST in a capitalist state like ours are still much better off than the middle class in china.
sheesh.
Don't get me wrong, I think that eventually we will have the technology to stage missions from Mars. However, I think that by the time we overcome some of the human related issues (long zero-g exposure, radiation, psycological, etc...) we will likely have made other advances that mitigate the benefit of launching from Mars over simply staging from Earth (i.e. cheaper access to space here at home).
I am not saying that Zubrin has misled you, and I never finished reading my copies of his books. He does an excellent job of pointing out the current deficiencies with our current technologies and policies, but I think he is overly optimistic in the alternatives that he suggests.
Why yes, I am ALSO a rocket scientist! :)
"It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
For one thing, you have to include the centripetal forces exerted on the satellite as it's orbiting. The Lagrange points are places where the centripetal forces exactly cancel the gravitational forces.
The L4 and L5 points are stable. If the satellite drifts out of position then the gravitational and centripetal forces acting on it will nudge it back into position.
But the L1, L2 and L3 points are unstable. If the satellite drifts even slightly then the gravitational and centripetal forces will not be cancelled and they will actually pull it further out of position. Even a very small force, like that exerted by the solar wind, would push it out of position given enough time. So a station at L1 would always need some kind of propulsion system to keep it positioned correctly.
See this link for more info.
Any system based on "runoff rounds" is going to fail. All the candidates need to be evaluated simultaneously not sequentially. Instant Runoff Voting is just a a dressed-up Plurality system; worse actually, because third parties are given the illusion that they can win. We need Condorcet Voting - cast votes in the same was as IRV, but count them differently. Condorcet is the only system I know of that allows voters to vote honestly instead of strategically - that in itself is a worthy goal for a voting system. Any good voting system must allow this liberty of conscience, and not ask voters to choose the "lesser of two evils".
Constitutionally Correct
Yes. And while all the Lagrange points are stable, the L4 and L5 points are even more stable (more massive objects can sit in them and catch the ride, as it were).
No. While all the Lagrange points are *balanced* - that is, there's no net acceleration towards either of the two objects, only L4 and L5 are stable. If you nudge something at L1,L2, or L3, they fall away.
L1 is between the two objects. This is obvious why it works: because one object pulls one way, and one object pulls the other way. Where the two pulls are equal, there's no net force.
L2 is on the other side of the (smaller) mass. Since it's farther away from the (larger) body, it should orbit slower than the (smaller) mass, but the added gravity makes it orbit at the same speed as the (smaller) mass, making it stationary.
L3 is on the other side of the (larger) mass. Same reasoning, just substitute "faster" for "slower".
All of these three are unstable: if you push something at L1, it goes towards the body you pushed it towards, ditto with L2,L3.
They talk about L1/L2/L3 because of the positional convenience of them. Yes, you have to active stationkeep, but this isn't impossible, and the drift rate would still be slow for reasonable timespans.
Regarding L4 and L5, L5 is more convenient than L4 because of dynamics of the Earth-Sun-Moon system, rather than just the Earth-Moon system.