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If iphone has at least 10^10 times the speed of apollo 11's circutry, then why are we still on earth? Where are the homemade apollos?
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M$1 Answer
Because fuel still weighs as much as it did in 1969. Rockets are big and heavy because it takes a lot of energy to lift something all the way to the moon, and no matter how fast the computers run, you can't change that.
And since the fuel for the later part of the trip has to be lifted during the first part as well, you need even bigger and heavier rockets. The problem is exponential, and most of the fuel was burned during the first few minutes, but you had to do it. The Saturn V is an enormous rocket to lift a tiny payload of humans and their capsule.
Circuitry shrinks, but fuel does not. We can make rockets a little smaller, but not radically smaller. A different kind of rocket using a very different fuel might change things somewhat, but that kind of innovation is rare and difficult. It might come from nuclear or fusion power, but that's dangerous stuff, requiring heavy shielding, adding weight. And while the stuff generates a lot of energy, getting it to generate a lot of power all at once requires a massive reactor. Fusion power is a dream on the ground, much less portable.
That's also what prevents homemade Apollos. Amateur rockets can barely lift themselves to 60 miles. Lifting themselves to 250,000 miles requires vastly more fuel, and remember, they have to lift the fuel as well as the rocket itself. It's far beyond any homemade budget.
And since the fuel for the later part of the trip has to be lifted during the first part as well, you need even bigger and heavier rockets. The problem is exponential, and most of the fuel was burned during the first few minutes, but you had to do it. The Saturn V is an enormous rocket to lift a tiny payload of humans and their capsule.
Circuitry shrinks, but fuel does not. We can make rockets a little smaller, but not radically smaller. A different kind of rocket using a very different fuel might change things somewhat, but that kind of innovation is rare and difficult. It might come from nuclear or fusion power, but that's dangerous stuff, requiring heavy shielding, adding weight. And while the stuff generates a lot of energy, getting it to generate a lot of power all at once requires a massive reactor. Fusion power is a dream on the ground, much less portable.
That's also what prevents homemade Apollos. Amateur rockets can barely lift themselves to 60 miles. Lifting themselves to 250,000 miles requires vastly more fuel, and remember, they have to lift the fuel as well as the rocket itself. It's far beyond any homemade budget.
You can leave an optional "tip" with Mahalo's virtual currency, Mahalo Dollars. If you are asking a difficult question that might require some research, or if you'd like a wide variety of feedback, a higher tip often leads to more answers to your question.
M$
Development of the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) could change this question of heavy fuel...
http://www.pbs.org/wgbh/nova/sciencenow/0403/04-diaz-nf.html
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VASIMIR doesn't solve the problem of lifting off the earth; it only operates in a vacuum. The specific impulse is high, but the thrust is very low, on the order of 400, compared to 1,000,000 for a chemical rocket.
One goal of the space station was to provide a waypoint for switching from the high thrust required for orbit, to something with the high specific impulse that can take you far if you've got some time to get there. Various kinds of thrusters are in test. VASIMIR is a good one but the first step is still the hardest.