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NASA Studying Solar Powered "Space Tugboat"
Zothecula writes "Last year, NASA announced it was seeking proposals for mission concept studies of a high-power solar electric propulsion (SEP) system that could be used in a 'space tugboat.' Such a ship would be used to ferry payloads in low Earth orbit (LEO) into higher energy orbits, including geosynchronous Earth orbit (GEO) and Lagrange point one (L1) — saving on fuel and the use of expensive secondary boosters. NASA also anticipates an SEP system could be used to propel spacecraft into deep space for science missions and for the placement, service, resupply, repositioning and salvaging of space assets by commercial operators."
Welcome to the 1970s? Solar panels + some kind of high ISP, extremely low thrust engine (used to be ion engines but apparently casamir effect thrusters are much better) have been planned ever since.
The problem is really simple. It's cheap to study a potential space travel mechanism on paper. But you cannot make any real progress unless real hardware is built and tested in space. And that costs a fortune, because a kilogram in space costs about $10,000 to get it there. Not to mention costs other than money, such as time and launch windows and delays and so forth.
SO...a rational person at NASA, if the organization was not at the mercy of Congress for every project, would dedicate ALL of their budget to getting that $10k/kilogram cost down to something affordable. Even if this took a large up-front investment to solve this problem.
Perhaps it's time for NASA to finally push forward its Stirling engine projects... They've been talking about it for at least a decade.
Ezekiel 23:20
with nothing to tug?
one would have to get shit into space for a reasonable cost before shuffling it around would be an issue
Dr. Einstein - a german patent clerk - has declared a galactic speed limit. It is estimated that this limit will extend our whale oil supplies well into the next decade.
How will this work at night?
solar powered sanitation satellite that just robotically collects debris in orbit, and when its payload is full it commits suicide by diving in to the atmosphere over the pacific ocean so what does not burn up on entry falls harmlessly in to the sea
Politics is Treachery, Religion is Brainwashing
This is exactly the kind of basic space infrastructure NASA should be working on. Space tugboats, construction vehicles, mining drones and assayers, cargo haulers, all the simple stuff that makes a civilisation run smoothly. We need to walk before we run, and that means mastering the basic techniques of constructing and operating these types of vehicles long before any thought is given to colonising the moon or Mars.
Oh, the tugboat goes, "toot-toot-toot",
Some toot high, and some toot low,
But the toot-toot-toot don't mean a hoot,
It's the chuga-chuga-chuga that makes 'em go!
Why, without your clothes, you're naked, Miss Dudley!
We need a STUDY?
A real quick estimate shows this is not terribly practical-- a square meter of solar panel is going to collect about 200 watts, under a quarter horsepower. That's going to be able to lift 100 pounds one foot per second. And that's ignoring the weight of the panel and of the reaction engine and of the reaction mass, and the energy needed to undo the orbiting speed. GEO orbit would take, oh, a whole lot more than 3.7 years to get to. The interest expense on a GEO satellite is so high you can't afford to have it loitering around for almost 4 years.
If it's going to be tendered out, doesn't that make it a 'Somebody Else's Problem' field'? (Hope they remember to use metric though).
Doesn't go nearly far enough. Just getting up through the atmosphere is not really the point. Balloons do that pretty well. The trick is to build a tower so high that
it reaches geostationary orbit, so the top of the tower is in orbit, not just in space. That's about 36000 km up.
Do you mean VaSIMR?
http://en.wikipedia.org/wiki/Variable_Specific_Impulse_Magnetoplasma_Rocket
Or Hall Effect Thrusters?
http://en.wikipedia.org/wiki/Hall_effect_thruster
And Ion Thrusters of various types have been used as primary propulsion n space successfully ever since Deep Space 1. They've been used for satellite orientation and station keeping for decades. They are vastly more efficient than chemical thrusters, reducing the amount of propellant you need to carry, and therefore reducing launch costs.
Basically this is a way to give money to companies for really not much. If you want to fund research you should fund it and publish the results or at least share them with other prospective developers. Nasa is paying 5 different companies to develop different concepts for the same thing. After which these companies will own their work and it won't be shared which results in Nasa basically getting a fraction of what they paid for. This is a very inefficient way to operate and probably one of the primary reasons we see little results from the massive amounts of money Nasa spends. I'm all for space exploration but this kind of wasteful spending is why Nasa's budget gets cut and more and more people feel a government funded space agency is a waste of money. If you want more value make it so that all the results are freely published and then we can build off it. That way the next contractor Nasa pays won't have to reinvent the wheel. Private company - government partnerships are IMO a very bad thing.
You can't have a space tug without a will-be was engine - sorry, just not possible.
What we need to do is to move the Eros asteroid o where we can smelt all those metals (including a lot of gold) into pure form, then get them all back on earth (without accidentally killing ourselves or the planet.) There's probably enough precious metals in it to literally pay off the national debt.
I read the title as "Tubgoat" and thought, as any normal person would, that it was about something like Tubgirl, but.. worse.
Opinions stated are mine and do not reflect those of the Illuminati