Hope of exploring the universe

[finster]

Because it is included in your plan. I'm just changing the timing of the launches.

 

Ok. something just clicked. I see what you're doing. And having everything with you would afford the possibility for altering course. To where, I don't know.

 

 

But what if we miscalculate the distance? What if something happens to the fleet that damages the supplies with us? We'll have 19,000 years to mess up along the way, breed some rogue captain with a death wish, mismanage and squander our supplies, etc, ad infinitum. Then what?

 

What if the star explodes before we get there? At the very least, we're going to want a supply chain going back.

Edited April 23, 2012 by finster

[Moontanman]

Got that figured out. Mother ships won't have to stop or adjust. As they close in on supply depots and unmanned mother and support ships, they send ahead smaller freight ships to collect supplies and drop off crew to populate the new ships. Easy peasy.

 

No not easy peasy, in a voyage like this, the mothership would be going so fast the possibility of the supply ships being useful is nil.

 

Think of it this way, you have a huge airliner, it's massive, taking off requires a huge amount fuel so to lighten the load you fly smaller support craft up to refuel the plane, food, water, what ever it needs. You even off load passengers like this the plane must fly as much as possible, it's always going faster and faster, each hook up very expensive in terms of energy expended. Can you imaging the failure rate of the off loads of "supplies" would be? The utter devastation if even one messed up?

 

But the most important part is the deta V of the mothership and supply ship, any going ahead, coming back or catching up, would require huge amounts of energy, far more than would be gained by the effort.

[zapatos]

Ok. something just clicked. I see what you're doing. And having everything with you would afford the possibility for altering course.

 

 

But what if we miscalculate the distance? What if something happens to the fleet that damages the supplies with us? We'll have 19,000 years to mess up along the way, breed some rogue captain with a death wish, mismanage and squander our supplies, etc, ad infinitum. Then what?

 

Well, we do risk management on all of that. For example, spread the fleet out more. Supplies don't have to be 1 hour away. If we are worried about, say, an explosion, maybe we put supplies one day, or one week away. Mismanaging our supplies can occur whether they are close by or far away.

 

What if the star explodes before we get there? At the very least, we're going to want a supply chain going back.

 

Well personally I believe that once they leave they are gone for good. We have to plan for them having the supplies and know how to care of themselves. When Columbus sailed it was do or die.

 

However, I never objected to supplies being sent after leaving. If you want that as part of your disaster planning I can see that being an option.

[finster]

No not easy peasy, in a voyage like this, the mothership would be going so fast the possibility of the supply ships being useful is nil.

 

Think of it this way, you have a huge airliner, it's massive, taking off requires a huge amount fuel so to lighten the load you fly smaller support craft up to refuel the plane, food, water, what ever it needs. You even off load passengers like this the plane must fly as much as possible, it's always going faster and faster, each hook up very expensive in terms of energy expended. Can you imaging the failure rate of the off loads of "supplies" would be? The utter devastation if even one messed up?

 

But the most important part is the deta V of the mothership and supply ship, any going ahead, coming back or catching up, would require huge amounts of energy, far more than would be gained by the effort.

 

 

Maybe we better plan for stops then. Perhaps swapping out ships altogether and relaunching at each point if and as supplies are needed. If supplies are not needed, which would be the plan, you could pass right by the supply depots. But they would be reassuring knowing they were there.

 

 

 

Well, we do risk management on all of that. For example, spread the fleet out more. Supplies don't have to be 1 hour away. If we are worried about, say, an explosion, maybe we put supplies one day, or one week away. Mismanaging our supplies can occur whether they are close by or far away.

 

 

 

Well personally I believe that once they leave they are gone for good. We have to plan for them having the supplies and know how to care of themselves. When Columbus sailed it was do or die.

 

 

Aha! So you admit that your plan is do or die! By your admission it is now logical to infer that if ships prior to Columbus had set up buoys filled with supplies at the mid-way point on the Atlantic Columbus's voyage might have been less than do or die! Now I've got you and Moontanman is my witness!

(just kidding)

 

 

 

[md65536]

how can you be absolutely sure you will launch with enough supplies to make it?

finster, you've made some interesting points about advantages to sending out unmanned missions but they've all been debunked. I think that you're missing the main point, which is that while it would be nice to have supplies "just there" waiting for you, any such supplies will be coming from Earth and must make the same journey that the people do, and ADDING an unnecessary separation between the supplies and the people doesn't gain you anything.

 

 

 

 

Here are two more reasons why one might send out early unmanned missions:

 

1) Testing/experimentation. For the same reason they sent monkeys into space before people, you might want to do the same. We might want to send out a test spacecraft to research problems that haven't been considered. If equipment is needed at the destination, it might make sense to send it out a couple years ahead of time, so that any problems it encounters might give the manned mission some time to prepare for, or something like that. On a large-scale journey, the benefit of doing this decreases. If it's a 1000-year journey, you probably wouldn't want to wait for the experiment to end before setting out, and besides you'd have 1000 years of technological innovation that the supply ship missed out on. Imagine sending moon exploration equipment in 1920s to prepare for manned missions in the 1960s.

 

2) The supply ships might do something useful while they're waiting for the humans. For example, if you had some method of gathering fuel in deep space, then unmanned ships might head out and start harvesting fuel. Then the manned missions don't have to bring all their fuel with them. However, if the unmanned supplies all come from Earth, you're bringing all your fuel with you whether manned or unmanned, and there's little point to sending it out ahead of time.

 

Another example is if you have a destination where a robot crew will go and build infrastructure. You may want to have a manned mission get to planet X and have a city built and waiting for them. On the other hand, with such a large endeavour, the ship you travel in is going to have to be home enough to live in for a long time, and it might just be easier to build one home instead of two and remain on the ship after you arrive. However, there is certainly much prep work and exploration that robots could do, with a much easier mission than with humans, so it could be done earlier.

[zapatos]

Here are two more reasons why one might send out early unmanned missions:

 

1) Testing/experimentation. For the same reason they sent monkeys into space before people, you might want to do the same. We might want to send out a test spacecraft to research problems that haven't been considered. If equipment is needed at the destination, it might make sense to send it out a couple years ahead of time, so that any problems it encounters might give the manned mission some time to prepare for, or something like that. On a large-scale journey, the benefit of doing this decreases. If it's a 1000-year journey, you probably wouldn't want to wait for the experiment to end before setting out, and besides you'd have 1000 years of technological innovation that the supply ship missed out on. Imagine sending moon exploration equipment in 1920s to prepare for manned missions in the 1960s.

 

2) The supply ships might do something useful while they're waiting for the humans. For example, if you had some method of gathering fuel in deep space, then unmanned ships might head out and start harvesting fuel. Then the manned missions don't have to bring all their fuel with them. However, if the unmanned supplies all come from Earth, you're bringing all your fuel with you whether manned or unmanned, and there's little point to sending it out ahead of time.

 

Another example is if you have a destination where a robot crew will go and build infrastructure. You may want to have a manned mission get to planet X and have a city built and waiting for them. On the other hand, with such a large endeavour, the ship you travel in is going to have to be home enough to live in for a long time, and it might just be easier to build one home instead of two and remain on the ship after you arrive. However, there is certainly much prep work and exploration that robots could do, with a much easier mission than with humans, so it could be done earlier.

I like those. And along those lines maybe one of your ships is sent out ahead, possibly with a crew, and begins growing and harvesting crops for food and other purposes.

 

And of course any research done when close to the new home is going to be much more detailed and informative than research done from earth.

[Purephysics]

So has the notion of attaining extraordinary speeds been left behind then?

[dimreepr]

So has the notion of attaining extraordinary speeds been left behind then?

 

 

Unless faster than light travel is attainable, which at present isn’t or ever likely to be, then the question of what percentage of light speed we achieve is moot. The more pressing question then becomes sustainability, how to maintain the crew long enough to find a suitable planet for colonisation. As Moontanman suggested an artificial eco-system is the only viable option. As taking enough supplies would be impossible, given the length of the journey is unknowable. As my previous post suggests this is achievable now (when I say now I mean in the next 25 years), if we had a sudden need to set up such colonies.

 

 

[stgeller]

Here is a science fiction story about how interstellar travel might become practical.

Specifically, it's about a trip to Sirius

http://berkeleybus.mysite.com/Interstellar_book.html