We Found a New and Cheaper Way to Get to Mars

Well actually two Mathematicians named Francesco Topputo and Edward Belbruno are proposing a new way to get to Mars. One that is cheaper albeit not faster than the traditional method. This new method is called Ballistic Transfer, and the old method is called the Hohmann Transfer. The new method will allow for more trips to the Red planet because proponents say that we don't need to wait for a launch window when the planets of Earth and Mars are closest.

Instead of shooting for the location Mars will be in its orbit where the spacecraft will meet it, as is conventionally done with Hohmann transfers, a spacecraft is casually lobbed into a Mars-like orbit so that it flies ahead of the planet. Although launch and cruise costs remain the same, the big burn to slow down and hit the Martian bull's-eye—as in the Hohmann scenario—is done away with. For ballistic capture, the spacecraft cruises a bit slower than Mars itself as the planet runs its orbital lap around the sun. Mars eventually creeps up on the spacecraft, gravitationally snagging it into a planetary orbit.

Hmm.m.m.m...Shoot your spaceship ahead of Mars and let the planet catch up to you.....? That sounds like a no-nonsense method, and one of those "why didn't I think of that moment(s)." With the potential for multiple trips to Mars, it sounds like the flood gates are about to open. What says ATS?

gizmodo.com...

a reply to: lostbook

Makes perfect sense to me, after all when we aim at a moving target, we aim for where the target will be not where it already is beforehand.

Lets just hope they have there math perfected and they don't miss.

a reply to: lostbook

Whats the relative closure "creep up on" velocity difference, if we know?

a reply to: lostbook

I think it is a more economical way to send rovers and maybe future supplies maybe even ahead of time to colonists but definitely not the best way to send colonists IMO.

Any scenario will take heaps of planning and risk assessments but that type of plan should allow for larger payloads. I am thinking they have probably thought of this before but technology has reached the point now where it is feasible.

originally posted by: intrptr
a reply to: lostbook

Whats the relative closure "creep up on" velocity difference, if we know?

That information isn't provided, however, I'm sure they're working on it...........

That's some logical thinking they propose. And I can imagine you could do the same with the return of the astronauts? I'll hope they don't miss the bus...

a reply to: lostbook

There are huge time pressures in these manned missions because they consume as they travel...let alone the muscle and bone loss due to zero gravity and radiation due to a lack of protection from the sun.

a reply to: lostbook

Lol, I agree. Relatively speaking, any injection burn into or in front of the destination planet is going to require similar amounts of fuel.

Maybe more. Instead of one orbital burn there is two. Not sure of terms just musing. Stuff in space is really moving…

The difference in travel time could be literally years.

The Hohmann transfer (and actually, this is technically incorrect. Hohmann assumes your craft and your destination is orbiting the same body. We use it to get to the moon as the moon and your craft are both orbiting Earth. Mars is orbiting the sun, and your craft is orbiting the Earth, so it's not really a Hohmann transfer), involves burning your engines at the right time for the right amount of time so that your craft leaves Earth orbit and heads out to where Mars will be.

Travel time for that method is measured in months.

Doing what they are talking about means burning (whenever you want) your engines so that your craft heads out away from Earth, and ends up in a solar orbit around the sun about the same orbit as the Earth.
Then, you have to burn again to increase your apogee so that it reaches about Mars orbit. Then you'd need to burn at apogee (which would take many months to get to) so that Perigee moves out to about Mars orbit also. You have to also make sure that your velocity around the sun is not quite that of Mars so the planet can catch up.

BUT, not only do all those burns take a long time, you have to be careful and not slow your velocity down too much, or else your orbit around the sun will be closer to the sun than Mars, and too far away for Mars to capture. So this means only going a little bit slower than Mars.

That means waiting, and waiting, and waiting and waiting some more for Mars to catch up to you.

Years can go by before that happens.

Not a viable solution for sending people to Mars as the longer they are in space, the worse it is for them (food, air water, cosmic radiation, solar flares, etc).

The only way to get to Mars quicker than the Hohmann transfer would be to have a rocket that can generate enough delta V so that the transfer can be done when Mars and Earth are a lot closer together, and of course to slow you down once you got there.

No one has a rocket that can do that right now.