Distance to Mars

[Eric Mc]

mrmr96 said:

Eric Mc said:

In 1,970, the Vice President, in his role as Chairman of the Space Task Group, gave NASA the objective of landing a man on Mars by 19,685. That was cancelled about a year later.

Not a particularly challenging timetable then?

Using an unfamiliar keyboard.

I meant 1970 and 1985 of course.

[benters]

not knowing the brief for the mission, what do they hope to find/do etc. . .I have clearly missed the reason why to go, or is it to prove it can be done ? i do not mean this with any negative intent, just curious

[Eric Mc]

It's a whole planet. It has the same land mass as the dry land areas of earth - so there are lots of things to explore and find out.
If we knew what was there in advance, there would be little point in going.

Mars is a fascinating planet, with a complex history and lots of hidden secrets that we have yet to find out. The proper exploration of Mars will take at least 200 years.
I'm half expecting that underground oceans will be found and vast reservoirs of underground water ice.

[Catatafish]

Eric Mc said:

It's a whole planet. It has the same land mass as the dry land areas of earth - so there are lots of things to explore and find out.
If we knew what was there in advance, there would be little point in going.

Mars is a fascinating planet, with a complex history and lots of hidden secrets that we have yet to find out. The proper exploration of Mars will take at least 200 years.
I'm half expecting that underground oceans will be found and vast reservoirs of underground water ice.

Yes it looks to be a geologistic's/single cell biologist's wet... frozen arrid dream. Lots of papers to come.

How long before it becomes an expensive and private place to live if you can afford to get away from the wall-to-wall humans that have filled every possible piece of space on earth.

[Eric Mc]

200 years.

[im]

Eric Mc said:

It's a whole planet. It has the same land mass as the dry land areas of earth - so there are lots of things to explore and find out.
If we knew what was there in advance, there would be little point in going.

Mars is a fascinating planet, with a complex history and lots of hidden secrets that we have yet to find out. The proper exploration of Mars will take at least 200 years.
I'm half expecting that underground oceans will be found and vast reservoirs of underground water ice.

Any cave structures would also be fascinating. I don't believe the Rovers or Orbiters have spotted any yet but there are bound to be many.

[Eric Mc]

They certainly have been imaged.






And evidence of running water - not from the distant past - but over recent months and years.

It truly is an amazing planet and well worth exploring properly.

[Einion Yrth]

mrmr96 said:

Here's something I don't fully understand: This "Slingshot" technique.

If the gravitational force of the planet or moon you're "slingshotting around" accelerates the space craft by pulling it in, then why doesn't the same gravitational force slow the space craft back down again once it's passed by?

Clearly the technique does work, but I just don't currently understand it. Any insight?

Cheers

What has to be noted about slingshots is that indeed relative to the target planet the spacecraft leaves at the same speed it arrived, however the planet is in orbit around the sun such that relative to the sun the craft can leave faster, or indeed slower, than it arrived.

[mrmr96]

Einion Yrth said:

mrmr96 said:

Here's something I don't fully understand: This "Slingshot" technique.

If the gravitational force of the planet or moon you're "slingshotting around" accelerates the space craft by pulling it in, then why doesn't the same gravitational force slow the space craft back down again once it's passed by?

Clearly the technique does work, but I just don't currently understand it. Any insight?

Cheers

What has to be noted about slingshots is that indeed relative to the target planet the spacecraft leaves at the same speed it arrived, however the planet is in orbit around the sun such that relative to the sun the craft can leave faster, or indeed slower, than it arrived.

Ok, that makes more sense. I was thinking in the wrong frame of reference (i.e. wrt the planet, not the sun. For interplanetary travel it makes sense to think of movement relative to the sun.)

[Steve Campbell]

Ref the "scale of things" ... I like this one

http://htwins.net/scale2/

[twin40s]

Eric Mc said:

As for the "private enterprise" missions that are being discussed at the moment, I'd like to know what rockets they intend to use to literally get the whole assemblage off the ground.

Edited by Eric Mc on Friday 15th November 14:04

If they wan't to go any time soon probably this: http://www.spacex.com/falcon-heavy

53,000kg to LEO, or apparently 13,200kg to Mars (Web page doesn't mention how long the mars trip would take though) yours for $135M

[Eric Mc]

It is the right direction to go. With the demise of the Saturn family of boosters, we have been severely handicapped in what we can do regarding putting lots of stuff into space with one launch.

Von Braun new that the secret of exploring the solar system and exploiting earth orbit and cislunar space was not the blind alley of false reusability - but the cost effectiveness of getting as much into space with one launch.

[Einion Yrth]

Eric Mc said:

It is the right direction to go. With the demise of the Saturn family of boosters, we have been severely handicapped in what we can do regarding putting lots of stuff into space with one launch.

Von Braun new that the secret of exploring the solar system and exploiting earth orbit and cislunar space was not the blind alley of false reusability - but the cost effectiveness of getting as much into space with one launch.

I don't believe that true reusability would be a blind alley, the fuel costs for a launch are, after all, a very small proportion of the cost. The problem is that the best we've managed so far is the ability to bring the used bits back in order to pretty much build another vehicle out of them.

[Hugo a Gogo]

true re-usability wouldn't be rockets, it would be a space elevator

[Einion Yrth]

Hugo a Gogo said:

true re-usability wouldn't be rockets, it would be a space elevator

We cross the atlantic in aircraft, not on a giant zip-wire. Not to say that a space elevator wouldn't have it's strong points, mind.

[Hugo a Gogo]

Einion Yrth said:

We cross the atlantic in aircraft, not on a giant zip-wire. Not to say that a space elevator wouldn't have it's strong points, mind.

america isn't in orbit

[Einion Yrth]

Hugo a Gogo said:

america isn't in orbit

Which has what to do with the price of fish? A truly reusable spaceplane would do just fine.

[Hugo a Gogo]

Einion Yrth said:

Hugo a Gogo said:

america isn't in orbit

Which has what to do with the price of fish? A truly reusable spaceplane would do just fine.

well you started with the irrelevant comments, the Atlantic on a zipline

once it's built, and (mined, presumably) stuff is coming down as well as up, a space elevator is free

launching rockets is very much small time, if you want to build large craft, you have to assemble them in orbit

it's like saying "I have a catapult in my garden to fire me onto the roof when I need to get to the first floor, why do I need stairs?"

[Einion Yrth]

Hugo a Gogo said:

well you started with the irrelevant comments, the Atlantic on a zipline

once it's built, and (mined, presumably) stuff is coming down as well as up, a space elevator is free

launching rockets is very much small time, if you want to build large craft, you have to assemble them in orbit

it's like saying "I have a catapult in my garden to fire me onto the roof when I need to get to the first floor, why do I need stairs?"

I don't see it as an either/or situation, should propulsive and materials engineering progress that far we could do with both. Bear it in mind that there are some very horrible things that can go wrong with an elevator, so you'd better be bloody sure that it's 100% not going to break. Plus I may not want to be in geosynchronous orbit, so some rocketry is going to be necessary anyway.

[im]

Hugo a Gogo said:

true re-usability wouldn't be rockets, it would be a space elevator

Never gonna happen...

http://io9.com/5984371/why-well-probably-never-bui...