Do you believe we can get to mars in 39 days?

[dreamer45]

Well do you???????????????????????????????

I'm not too sure. You know, a trip thats meant to take 12 months and now all of a sudden they can do it in 39 days hmm? And if this were true wouldn't we be declaring this as a mission and do whatever we need to invent the technicology and to make it happen.

Why the hell don't we know how we got here?

 

[PiotrSatan]

Mars in 39 days? Well I think that if such technology existed then so far we would know every single moon and planet in our solar system by a year or 2 years time. I doubt it. You have to take food supply, special life support system that cannot break, tools in case something goes messed up and so on. If ship went that fast and something broke outside then astronaut going outside would be simply either left behind or just killed due to collision with one of the parts.

 

[nimbus]

Why is this a matter of faith?
The VASIMR 39 day to Mars configuration just needs a huge (by today's standards - no space nuclear reactor even exists) input of power, on paper. There's also the engineering challenge of waste heat. Sort of like F=ma, making this happen is increasingly expensive the sooner you aim to make it happen. And probably not linearly. Then you add the rest of the $$$: the whole mission cost. It balloons way beyond current space budgets.

 

[js117]

This should be merged into
VASIMR updates
or
faster way of geting to mars

 

[docm]

Agreed since the engine tech is so close with VASIMR.

39 days is possible with a 200 mW reactor, bit that's a tough build. That said Chang-Diaz has also said that a 10-12 mW reactor could do a slightly longer trip, and that power level is very do-able.

 

[EarthlingX]

If you are willing to read, if possible before posting, here are some forum threads :
FASTER WAY TO GET TO MARS???

List of Multiple Threads on the Same Topic

 

[pathfinder_01]

Well do you???????????????????????????????

I'm not too sure. You know, a trip thats meant to take 12 months and now all of a sudden they can do it in 39 days hmm? And if this were true wouldn't we be declaring this as a mission and do whatever we need to invent the technicology and to make it happen.

How long it takes to get to mars depends on the method used to get there. A good analogy is a horse vs. an early steam locomotive. Both are capable of reaching 30mph, but the horse can only do so for a very brief time while the steam train can do it much longer.

Electric propulsion works differently than chemical. In chemical rocket all the energy needed for the trip is generated in a few minutes. Electric propulsion generates the delta V in a matter of hours, days, weeks, or even years.

Electric propulsion has two advantages over chemical:

Higher exhaust velocity makes higher speeds than chemical possible.

Electric propulsion is much more "fuel efficient" than chemical...higher ISP. So electric propulsion can do the same work as a chemical rocket for much less mass of propellant.

Electrical has one big downside over chemical

Low thrust. In fact the reason why Vashmir is so hyped is because it gives enough trust to be useful on a manned mission to mars. These rocket have so little thrust they could not even lift themselves off the ground! However a small force acting constantly against a mass in space(where there is no friction to stop it) will cause the mass to accelerate.

On a short trip say to the moon, the electric rocket will not have had enough time to gain a speed advantage over a chemical one. It would take vashmir a few weeks to get to the moon while a chemical one could do it in a few days. The vashmir rocket would need less propellant to do so and could be a cheap way to send cargo to the moon, but it would expose the crew to much more radiation in the Van Allen belt than a chemical one.


On a longer trip say to mars an electric rocket could easily equal or beat a chemical one in terms of trip time. It could allow you to carry more mass or get there faster.

The show stoppers are not so much the engine itself but other things.

1. Electrical propulsion requires lots of electric power. The more of it the better. In the case of the 39 day trip you need a space usable 200kw source of power that does not have too much mass (or else the thing will accelerate too slowly) . You can do a slower trip with a 14kw reactor and this kind of reactor is not too far from being able to work in space. Solar is also possible but not as desirable as nuclear from a mass stand point, however NASA is looking into developing a solar powered lunar tug.

2. The engine must work for the required amount of time which is much longer than a chemical rocket. It must work non stop for months to get to mars.


The theory behind the engine is sound. It just the engineering that is the problem. Sort of like liquid fueled staged rockets in the late 19 century. It would take 20 th century engineering to bring that idea to life. At this point vashmir needs in space testing to ensure that the engineering problems have been solved and that it’s performace/lifetime are acceptable under space conditions.

 

[halman]

Well do you???????????????????????????????

I'm not too sure. You know, a trip thats meant to take 12 months and now all of a sudden they can do it in 39 days hmm? And if this were true wouldn't we be declaring this as a mission and do whatever we need to invent the technicology and to make it happen.

Why the hell don't we know how we got here?

If we put a Saturn 5 in orbit, fully fueled, with a payload of 10 tons, we could probably reach Mars in a matter of hours. Of course, we wouldn't be able to stop, so that payload would go 'splat' on the Martian surface. If we use the same Saturn 5 to send 100 tons to Mars, we could stop, enter orbit, and come back in a matter of weeks. If we want to land, and return to orbit so that we can come home, the voyage will take several months, round trip.

If everyone in the United States wanted to go to Mars more than anything else in the whole wide world, we would figure out how in short order. It would not take too much longer to figure out how to go there and be able to come back, too. The only problem is that very few people want to go to Mars right now. I don't, and I have been a fan of space exploration since before the Apollo program.

 

[pathfinder_01]

Well do you???????????????????????????????

I'm not too sure. You know, a trip thats meant to take 12 months and now all of a sudden they can do it in 39 days hmm? And if this were true wouldn't we be declaring this as a mission and do whatever we need to invent the technicology and to make it happen.

Why the hell don't we know how we got here?

If we put a Saturn 5 in orbit, fully fueled, with a payload of 10 tons, we could probably reach Mars in a matter of hours. Of course, we wouldn't be able to stop, so that payload would go 'splat' on the Martian surface. If we use the same Saturn 5 to send 100 tons to Mars, we could stop, enter orbit, and come back in a matter of weeks. If we want to land, and return to orbit so that we can come home, the voyage will take several months, round trip.

If everyone in the United States wanted to go to Mars more than anything else in the whole wide world, we would figure out how in short order. It would not take too much longer to figure out how to go there and be able to come back, too. The only problem is that very few people want to go to Mars right now. I don't, and I have been a fan of space exploration since before the Apollo program.

I think most people want to go to mars or the moon. Or at least are not opposed to it. It is just a matter of unwilling to spend the cost for current capability. It is sort of like the pony express. The pony express could get a small package from cost to cost but a rail line could move the package faster, could move much larger packages as well as people and the telegraph removed the need to send a message via paper at all over the distance.

This is what needs to happen to spaceflight. Cheaper access to LEO and quicker more mass efficient access to deep space. Imagine if the moon were like the Antarctic. There are many scientists there as well as a program to send artist there. This works because it only costs millions to support an Antarctic base while with current technology moon base or mars base support could get into the billions.

 

[halman]

pathfinder_01,

There are a great many people in the United States who believe that spending on space exploration is wasted money. I am not saying the majority, but still a large number. When you consider that the United States is not going to be able to even put humans in Low Earth Orbit in a matter of months, talking about going to Mars seems a little, no, a lot off the wall.

I am convinced that we need to take small steps, to prove our technology, and to allow commercial development of space. To this end, I have proposed something which is detailed in "A cheap and easy way into space", which is in its own thread in this forum.

 

[rockett]

I am convinced that we need to take small steps, to prove our technology, and to allow commercial development of space. To this end, I have proposed something which is detailed in "A cheap and easy way into space", which is in its own thread in this forum.

I am in full agreement with you on that halman. I have been following your thread on "A cheap and easy way into space", and like it because it addresses the biggest problem and that is getting off of the ground in the first place.

We need to take it a step at a time. Apollo for instance was a "hurry up and get it done" approach which we abandoned. The Shuttle was purpose built to construct ISS. Neither was meant to be an incremental approach...

 

[rockett]

There is a LOT more information about this topic on these threads:

FASTER WAY TO GET TO MARS???
http://www.space.com/common/forums/viewtopic.php?f=15&t=23002

VASIMR Updates
http://www.space.com/common/forums/viewtopic.php?f=15&t=19731

Can we do it? SURE! We just need the money and the will to accomplish it. As for power, there was a neat little reactor mentioned on one of the above threads:
http://www.hyperionpowergeneration.com/

 

[pathfinder_01]

pathfinder_01,

There are a great many people in the United States who believe that spending on space exploration is wasted money. I am not saying the majority, but still a large number. When you consider that the United States is not going to be able to even put humans in Low Earth Orbit in a matter of months, talking about going to Mars seems a little, no, a lot off the wall.

I am convinced that we need to take small steps, to prove our technology, and to allow commercial development of space. To this end, I have proposed something which is detailed in "A cheap and easy way into space", which is in its own thread in this forum.

I agree. I think that if NASA turns over manned spaceflight to the private sector there can be savings. NASA could then focus on cost effective ways to get into LEO and deep space. I like the ideas behind electric propulsion and propellant depots because with them it may be possible to go into deep space for nearly the same cost as a LEO mission with the shuttle.

I hated constellation because it seemed to provide no advantage other than replay Apollo. It was a let's trade the shuttle which could do 4-6 flights a year to LEO and the ISS for 2 flights to the moon. If NASA develops an unmanned heavy lift(say 50ish tons to LEO) that is a bit cheaper than the shuttle and uses private spaceflight to get to from LEO then the way could be cleared for missions to the moon and beyond.

I think a shuttle like vehicle could be an asset for down mass capability and construction. What I think went wrong was not developing the shuttle into something cheaper or safer and using it as a pseudo space station for it's first ten years. I also don't think that you would need 4 of them(maybe one or two). I would like the US to replace this capability, but don't think it needs to be high priority. I think the two high priority items should be electric propulsion and fuel depots. They help decouple the needs of LEO from the needs of deep space. Imagine how much more could have been done with Apollo if the crew had access to a lunar space space station and additional landers when they arrived at the moon.

I think there is a certain budget congress is grudgingly willing to give NASA and that what ever plans NASA has needs to be done within that budget and within a reasonable amount of time(No more 20 year moon plans or big gaps in capability).

 

[bdewoody]

It looks like to me that until or unless private industry sees a profit motivation to develope the vehicles needed to go to the moon and beyond we will have to be satisfied with looking at video generated by robotic rovers on the various planets and moons we want to explore, at least here in the USA. Maybe Europe or the Chinese or the Japanese will have the foresight to see that no matter what the initial costs are the return in the long run justifies said costs and risks. A lot of people here in the USA are no longer willing to push ahead where the risk of loss of life is higher than that taken by going for a walk in the park.

So my answer to the Mars in 40 days question is, yes I believe we will be able to do it but most likely it won't happen for a couple of generations.

 

[rockett]

A lot of people here in the USA are no longer willing to push ahead where the risk of loss of life is higher than that taken by going for a walk in the park.

I'm afraid you are right, there. We seem to have a delusion that we can make space travel "safe". I remember the high casualty rates among the X plane pilots. While I don't advocate anyone deliberatly dieing for a cause, we should be realistic about it. Space is one of the most hostile environments known, and getting up there even more dangerous. We have become so risk aversive, we really do expect all gain and no risk at all. Not even air travel or driving a car has that, it wouldn't be sane to think so. Machines can fail and so can people. Either can be fatal.

Maybe that's why we don't seem to have the "Right Stuff" anymore...

 

[DarkenedOne]

It looks like to me that until or unless private industry sees a profit motivation to develope the vehicles needed to go to the moon and beyond we will have to be satisfied with looking at video generated by robotic rovers on the various planets and moons we want to explore, at least here in the USA. Maybe Europe or the Chinese or the Japanese will have the foresight to see that no matter what the initial costs are the return in the long run justifies said costs and risks. A lot of people here in the USA are no longer willing to push ahead where the risk of loss of life is higher than that taken by going for a walk in the park.

So my answer to the Mars in 40 days question is, yes I believe we will be able to do it but most likely it won't happen for a couple of generations.

I do not think the private industry is strictly driven by profit. If you look at many of these small space companies they are driven by the dream of finding and exploiting commercial uses of HSF. Of course being a private company means that you do not have hundreds of billions to waste like NASA does. In order to do so they have to lower the costs by which certain activities are conducted.

For example SpaceX hopes to put people into space at $20 million per ticket.

 

[Swampcat]

I do not think the private industry is strictly driven by profit. If you look at many of these small space companies they are driven by the dream of finding and exploiting commercial uses of HSF. Of course being a private company means that you do not have hundreds of billions to waste like NASA does. In order to do so they have to lower the costs by which certain activities are conducted.

For example SpaceX hopes to put people into space at $20 million per ticket.

Just to follow up on this, Elon Musk has stated that his purpose for creating SpaceX was to put humans on Mars. Making a profit for his company would definitely make that end result more likely, but he has no stockholders to satisfy and appears to be willing to put his own fortune at risk to promote the colonization of Mars.

Of course, he is the exception to the general rule and realistically he is going to have to sell launch services and/or seats on Dragon to make it happen.