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NASA's 'Inspirational' Mars Flyby
astroengine writes "The idea of slingshotting a manned spacecraft around Mars isn't a new one. In the 1960's, NASA carried out a feasibility study into an 800-day flyby mission to the Red Planet. And it would have been awesome. AT&T/Bellcomm mathematician A. A. VanderVeen was working for NASA in 1967 and came up with 5 possible launch opportunities between 1978 and 1986 — two windows in 1979 and 1983 provided the shortest transit time between the planets. But launch mass and fuel requirements were a constant issue. So VanderVeen turned to physics to find an elegant, and scientifically exciting, solution: add a Venus flyby to the Mars trip. Mars, Earth, and Venus align with the sun five times every 32 years, but Venus and Mars alignments happen more frequently making double (Earth-Venus-Mars-Earth) or even triple (Earth-Venus-Mars-Venus-Earth) flybys a viable mission. Unfortunately, the flyby never happened."
Short answer: the ISS weighs 495 tons. That's a LOT of mass, and would take a lot of fuel, which itself would take even MORE fuel to get into orbit. A better compromise would probably be something like a small capsule with a habitat module, sort of like the Spacelab module for the shuttle.
Furthermore, the mission profile for a single launch to orbit ejection is much simpler than multiple launches, docking, building a spacecraft in orbit, and then orbit ejection.
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They didn't even have video games to amuse themselves with back in those days.
Are we there yet?
In his novel, Voyage.
Basically, back in '69, NASA decided on Mars instead of the Shuttle, and everything was sacrificed on the altar of Mars. The NERVA had a horrendous in-flight failure, so they had to go back to chemical, and they chose the Earth-Venus-Mars-Earth trajectory.
I'm guessing he read the old documents on this.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
What's the point of a manned ballistic fly-by? All the humans can do is operate some instruments for the brief period they're slingshotting around the planet.
The problem with flybys is that they have most of the complexity of a real Mars mission but don't actually achieve much of anything. You have to survive in deep space for a year or more, but all you see of Mars is a fleeting glimpse over the course of a few hours as you zoom past. Venus is even worse, because there's really nothing to see other than clouds.
They made a very limited amount of sense when unmanned spacecraft were really dumb, but they make just about no sense today. At best you'd be testing deep space tech for human spaceflight, but you can test it about as well and much more safely in high Earth orbit.
All talks of "manned flight to Mars" centered around getting living human beings into a little confined spaced for hundreds of days
Even if every single thing works out - no one die on route, no accident, no nothing - it would still be an extremely cramped up place for human beings, and the psychological trauma of cooped up inside a holding cell for hundreds of days isn't something easy to deal with
But what if something goes wrong ?
What if one of the occupants die in route ?
What then ?
Is there any "escape plan" built in ?
How to deal with the rotting corpse ?
Muchas Gracias, Señor Edward Snowden !
Two flybys of Venus and even one of Earth on the way to Saturn
Galileo flew by Venus once and Earth twice on the way to Jupiter
There are other interesting gravity assists but I'm not aware of any that flew by Venus en route to Mars.
The moon could be used to change the plane of the resulting solar orbit though.
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I never completely understood the need of launching massive ships from Earth whenever we want to leave it. Whenever we wanted to travel the seas, we did not build a massive caravel inland then painstakingly dragged it all the way to the coast. We reasoned it made more sense to build it in a dry dock, that way it only requires a tiny push to get it into the ocean.
Wouldn't anyone at NASA think that making a "Space Dock" made sense?. Make a bunch of tiny trips to lower earth orbit and build the ship there, so you can make a larger ships to travel further. Mass would not be such a big issue (granted, fuel would be), but at least the escape velocity problem would be non-existent.
Why not just take some volunteer who's on death row or something? Make an agreement that if he makes it back successfully, then he gets to go free.
Oh yeah, and he has to rescue the president from crazed hostile maniacs.
Now, as then, if NASA doesn't solve the problem of shielding the astronauts from solar radiation and cosmic rays you might just as well call it; The Mars Fryby!!!
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All the plans I've seen so far involve single launches, which dramatically decreases the things a manned vehicle can accomplish on a mission outside Earth's orbit. They have the ISS right there, why not launch three or four modules, strap them together next to the ISS, and then go for Mars with quite a bit more breathing room?
If you have "three or four" modules instead of one, you're also gonna need three or four times the amount of fuel and rocket thrusters, which weighs much more than the modules themselves. In additional to strapping the modules together, you'll also need to strap those thrusters and their fuel tanks together and make them work in a coordinated fashion as one large rocket drive. That's never been done before.
What's the advantage to using the ISS as a staging point, as opposed to assembling the vehicle in its own orbital slot? Are you envisioning the ISS acting as on orbit housing for a team of assembly mechanics?
When our name is on the back of your car, we're behind you all the way!
They made a very limited amount of sense when unmanned spacecraft were really dumb, but they make just about no sense today. At best you'd be testing deep space tech for human spaceflight, but you can test it about as well and much more safely in high Earth orbit.
You are totally correct. How utterly pointless a flyby is.
Im sure doing something for the fact that nobody in human history has ever done it before, being in the history books, the prestige and kudos that comes with it, im sure none of those things have ever had anything to do with human exploration. Im also sure the engineering and science advances that come out of a flyby like this also has nothing to do with it. Nor would be the information gathered from doing 90% of a Mars landing be of any use too.
amiright?
...I'd be willing to bet that most of humanity don't know who Stafford and Cernan are (if you had to look them up to figure out why I mentioned them, I win). The names of Armstrong and Aldrin will be remembered by the average man on the street as long as our species survives.
This only begins to make sense when you don't have to lift all the raw materials out of the gravity well anyway.
Think asteroid mining. Then think refining, manufacturing, assembly, QA, and everything else that needs to be done before the parts for your spaceship can turn up at the dry dock.
Venus and Mars are alright tonight?
Ubi dubium ibi libertas: Where there is doubt, there is freedom.
With new materials coming on-line it can not be far-a-way from the time we can build a space elevator
If they're not going to actually land, what exactly is the point of manning it? To reduce the couple minute delay on controls by having a human on location? Well, a robot can stay there for years so time isn't a real big thing unless everyone's just that impatient.
Or just get it over with already and route the flight through Atlanta.