Thread: Satellites

How many satellites inside of this solar system have we sent probes to? Satellites like Europa seem so interesting, it is amazing that not much has been done to send something there. Just look at pictures from space of the surface; a giant ice sheet with thousands of valleys in it. Imagine standing there on an ice sheet overlooking a valley made of ice hundreds of times larger than the Grand Canyon. Forget Mars, there is nothing there but red dust and rocks, not too different from some places on earth. On Europa, not only is it exponentially more beautiful and interesting, but many scientists think that there could be life in the proposed oceans beneath the ice.

You are free to propose such a mission. It is just that it would have to compete other interesting things to be investigated. In the end, it is just a matter of money. Getting to Mars is much cheaper. Just to give you an idea, here is a link to missions considered for the future:

http://www.esa.int/esaCP/SEM1IQAMS7F_index_0.html

we have to get to mars if we are going to go farther out into the solar system. we need re-fueling stations on mars, to make the rest of the solar system accessible. Just as we need to go back to the moon to go to mars.

Originally Posted by SuperNatendo

we need re-fueling stations on mars, to make the rest of the solar system accessible.

If time is an issue, yes. We're an impatient lot. That skews our judgment. And if we can't learn patience, as a species, no hope anyway!

IMO, the primary goal should be deep probe into Europa. Preparation to inoculate. 'Cause I think it's gonna be a long long time.

Originally Posted by SuperNatendo

we have to get to mars if we are going to go farther out into the solar system. we need re-fueling stations on mars, to make the rest of the solar system accessible. Just as we need to go back to the moon to go to mars.

I doubt that anyone who wants to go from the Earth to Jupiter (or anywhere else) is going to stop Mars to refuel along the way. Once you are actually in earth orbit, it takes about the same amount of fuel to go anywhere in the solar system. For the amount of fuel that it would take to go to Mars, you might as well just go to whatever planet you ultimately want to get to. Not to mention the fact that most of the time the planetary orbits won't line up right for Mars to acts as a convenient stop along the way. Jupiter isn't even in the same orbital plane as Mars.

It infuriates me that not much will get done until I am dead. Its pathetic that my body without my permission will just kill me off before I get to see certain things happen. We could do some really amazing things within my lifetime if the population of earth devoted itself to science, but that will never happen (uhuhuhuhuhuhbecauseofreligionuhuhuhuhuh).

Originally Posted by Scifor Refugee

Once you are actually in earth orbit, it takes about the same amount of fuel to go anywhere in the solar system... you might as well just go to whatever planet you ultimately want to get to.

Forgot the slingshot trick. We've used Mars this way before. And since you're passing by, may as well have Mars radio relay, Mars bottled water, Martian hitchhikers...

Originally Posted by Pong

Forgot the slingshot trick. We've used Mars this way before. And since you're passing by, may as well have Mars radio relay, Mars bottled water, Martian hitchhikers...

Ah yes, I did forget about that. But I still don't think it would be a good solution for routine travel. You might have to wait years to get everything lined up right for it to work for whatever destination you're traveling to.

Not if you had a permanent mars base, whether manned or unmanned. Everything you need could be ready and waiting when you got there for many different missions.

The point is, we need to establish a moon base for refueling, water, emergencies etc, and we may need to do the same to mars before we attempt a trip to one of Jupiter's moons. At least as far as manned missions are concerned. We have to crawl before we can walk.

But, if we really applied ourselves, these could be done and by 2050 a trip to Jupiter would not be as hard, dangerous or expensive.

Pffffff, I am tired of Newtonian physics. Instead of putting a tremendous amount of effort into something with so many problems and limitations, we need to put our resources towards an entirely new method.

Originally Posted by Cold Fusion

Pffffff, I am tired of Newtonian physics. Instead of putting a tremendous amount of effort into something with so many problems and limitations, we need to put our resources towards an entirely new method.

how did we go from mars bases to discussing the relativity of Newtonian physics?

Originally Posted by Scifor Refugee

Originally Posted by Pong

the slingshot trick.

But... You might have to wait years to get everything lined up right for it to work for whatever destination you're traveling to.

True. So dumb luck really could derail our travel plans and destiny as a species. Homo sapiens waits for the bus. I see why Cold Fusion's steaming.

SuperNatendo, the planet or moon is far more useful as a gravity well to slingshot around than a landing pad to refuel on. As long as you don't crash or orbit, you come out of the turn with added velocity. We might even get real good at that, lapping ever faster around, say,
Earth->Moon->Mars->Venus->Earth->Moon... etc.

Did I say you had to land in order to refuel? No, I did not! It could easily be setup in a way where fuel converted from the atmosphere of mars and water melted from the ice of either mars or the moon and other materials one might need could be launched into orbit from the moon and or planet where they could be docked with much more efficiently than landing and re-launching.

I like that idea a lot. You could launch fuel to intercept a vehicle. Since the can 'o fuel is hauling nothing but itself, getting up to matching speed is no biggy. This approach is just the opposite of our staged rockets. Taken to extreme, you'd string the fuel along the route beforehand, then vehicle consumes it Pac-Man style. Much less fuel needed to get started, and overall savings.

Originally Posted by Pong

I like that idea a lot. You could launch fuel to intercept a vehicle. Since the can 'o fuel is hauling nothing but itself, getting up to matching speed is no biggy. This approach is just the opposite of our staged rockets. Taken to extreme, you'd string the fuel along the route beforehand, then vehicle consumes it Pac-Man style. Much less fuel needed to get started, and overall savings.

The problem is that the fuel would have to match velocities with the ship before the ship could grab it, or you'll just have the fuel and ship flash past each other at several km/sec. Suppose a ship is doing a Mars sligshot fly-by at 3 km/sec. If you launch 10 tons of fuel, you will need to burn about 5 tons of it just to get the remaining 5 tons up to the 3 km/sec of the passing ship. I'm not saying that it couldn't work, I'm just saying that I don't think it will ever be a good solution for rutine travel. Unless you don't mind waiting years between missions for the planets to align correctly.

Space fountains can be built on various solar system bodies with docking stations on top where you can refuel and restock if needed with a relatively low energy waist.

Originally Posted by Scifor Refugee

I'm not saying that it couldn't work, I'm just saying that I don't think it will ever be a good solution for rutine travel.

It depends on trip type and frequency. Infrequent, manned missions, we want to do 1g to midway, then turn around and brake for 1g until full stop (or destination orbit - close enough). That's optimal for any trip over a few days. Long trips like to neighbouring stars, take 50-100 years this way - and there's no other way. Later, we want as much fuel again to return home. If we pack all that in one ship, the inertia is enormous. Why cars don't tow enormous gas tanks.

I think we can do better than fixed gas stations in space, because any fuel we shove off may as well keep going - it is wasteful to brake the fuel and have it waiting. At least we could time a shipment to arrive at destination when complete mission needs to head back.


How about a stream of fuel? Fire that out of nicely tuned nozzle, beforehand. Then lightweight ship conceptually formed like tapered tube, burns fuel in passing. It would have to be timed and balanced nicely, but we've proven our precision in space maneuvers - we can pull that off I think. What kind of fuel? It should burn steadily.

Originally Posted by Pong

It depends on trip type and frequency. Infrequent, manned missions, we want to do 1g to midway, then turn around and brake for 1g until full stop (or destination orbit - close enough). That's optimal for any trip over a few days. Long trips like to neighbouring stars, take 50-100 years this way - and there's no other way.

If you accelerate constantly at 1 G you can reach alpha centauri (4.4 light years away) in just 3.6 years ship time, or 6 years earth time. Not that anyone has any serious ideas about how to make a ship accelerate like that.

The space fountain, does it use a Gaussian accelerator at the top?

I know all of you guys are too stuck up to play any video games or watch anime , but if any of you have seen Cowboy Bee bop, they appear to use a version of the space fountain; the difference is that each loop is in orbit around the planet and gathers energy from solar panels (so it seems). This design could work even better.

I am going to go off topic even more......apparently NASA a while ago sent up a inductive tether attached to the space shuttle, that generated kilo watts of energy just buy going through the earths magnetic field. Wouldn't this be considered a source of unlimited energy?; or does it take allot of power to keep the shuttle in orbit?

Originally Posted by Scifor Refugee

If you accelerate constantly at 1 G you can reach alpha centauri (4.4 light years away) in just 3.6 years ship time, or 6 years earth time. Not that anyone has any serious ideas about how to make a ship accelerate like that.

Or that any body could endure the sudden stop. See, just when you're getting up to a good clip, it's time to turn around and start braking.

Originally Posted by Cold Fusion

or does it take allot of power to keep the shuttle in orbit?

The shuttle normally lives in low orbit where there is significant drag.

What about the ISS? It only gets its energy from solar panels- adding an inductive generator could make a surplus of energy for it; they could even beam the energy down to earth if they are eventually able to generate enough power.

Is the drag caused by the atmosphere? or some other effect?

Originally Posted by Cold Fusion

What about the ISS? It only gets its energy from solar panels- adding an inductive generator could make a surplus of energy for it; they could even beam the energy down to earth if they are eventually able to generate enough power.

You get 1400 watts per square meter up there (if 100%), which is not mind blowing but sufficient. On the other hand, getting rid of spent energy (heat) is a problem. Maybe ISS could beam it at something?

Originally Posted by Cold Fusion

Is the drag caused by the atmosphere? or some other effect?

Atmosphere - if I'm not mistaken that's why Skylab crashed.

Originally Posted by Pong

Or that any body could endure the sudden stop. See, just when you're getting up to a good clip, it's time to turn around and start braking.

I was talking about 1 G of acceleration for the first half and then 1 G of constant deceleration for the last half.

Originally Posted by Cold Fusion

I am going to go off topic even more......apparently NASA a while ago sent up a inductive tether attached to the space shuttle, that generated kilo watts of energy just buy going through the earths magnetic field. Wouldn't this be considered a source of unlimited energy?; or does it take allot of power to keep the shuttle in orbit?

Even ignoring the effect of drag from the atmosphere, the tether would slow down as it interacted with the earth's magnetic field to produce electricity. You are basically slowly trading the kinetic energy of the tether (that you built up when you launched it from a rocket) for electrical energy.

I feel like whenever we seem to discover a source of limitless energy, the universe puts up a big middle finger while laughing at us, shaking its head back and forth saying, "ah ah ah, I don't think so".
It pisses me off.

No source of energy is limitless. Even the Sun will burn itself out one day.

The best way I think to get a lot of power, is to treat the sun more like the fusion reactor that it really is. We can utilize more power from the sun by finding means to convert the energy it produces, whether using solar panels, or converting some of the other energies by using satellites placed in a stable close-orbit to the sun. This increases our efficiency at catching a higher amount of energy than we can from the distance of our planet. We simply transmit the energy in the form of microwaves to be easily converted in power sources wherever we need it.

Originally Posted by SuperNatendo

satellites placed in a stable close-orbit to the sun. This increases our efficiency at catching a higher amount of energy than we can from the distance of our planet.

That's brilliant. Collect & beam. How about a cheap foil dish, and a few nice lenses to beam it pure? Place several in orbit, beaming though each other - around the sun - when Earth is out of sight.

You could also use that to cook asteroids in the belt, for processing.

Everyone here needs to realize that Pong is a proud sarcastic guy. When it seems as if what he is saying is even in the slightest bit absurd, then the rest of what he said/says is also sarcasm. Nevertheless, it will not annoy you once you can instantly find it without remarking in a way that does not follow his true intentions.

Lets break down how I determined that Pong was being sarcastic.

1. Notice, "That's brilliant". Looking back on the amount and lack of knowledge that he possesses, remarking this is much of a surprise. When you statistically calculate the percentage of posts that he views, there is approximately a 94% chance that he has viewed a post directly mentioning this idea. Now, as far as I can recall, he never responded in such a way, and has been exposed to this idea a multitude of times. Due to this, you can surmise that either 1. Pong is stricken with amnesia or 2. He is attempting to be sarcastic.

2. "You could also use that to cook asteroids in the belt, for processing". A couple of months ago I would not have caught this, but after receiving multiple lessons in sarcasm without vocal tone from Ophiolite, I have attained to ability to find sarcasm in even the most unlikely places. (Thank you Ophiolite, a free lesson in English is always delightful) Now, I may not have the hard evidence that people on this forum crave so badly, so I humbly ask all of you to understand my intellect, and bear with it.



I know JB. The thing is that I see myself in competition with the universe. We are in a sharp sworded battle to see who can get the better of the other. Nothing is impossible; it only might not be obtainable within my life time.

We not only could create a star on earth and source tremendous amounts of energy for a comparatively minuscule input, but we could also try splitting particles further (not sure how feasible that is though...)

Originally Posted by Cold Fusion

Everyone here needs to realize that Pong is a proud sarcastic guy...

You may be right, but not that time.

Hey wasn't there some dude posting about TVs ogling people... and we all said "Nah, who'd bother..? Too much effort.."