Astronauts bound for Mars should swing by Venus first, scientists say

[Admin]

To get to Mars cheaper and faster to save time and open up new mission windows, scientists say there's an easy shortcut: fly by Venus on the way.

Astronauts bound for Mars should swing by Venus first, scientists say : Read more

 

[Andrew N]

To get to Mars cheaper and faster to save time and open up new mission windows, scientists say there's an easy shortcut: fly by Venus on the way.

Astronauts bound for Mars should swing by Venus first, scientists say : Read more

Speed increase?
Time savings?
Extra braking requirements on reaching Mars?

 

[Matthew Bruder]

There is an interesting 1967 study which considered a fly-by of Venus with a continuation to Mars.

 

[Helio]

That's great news. It reminds me of the idea to build a tunnel from NYC to LA where the travel speeds in a vacuum tube on a magnetic rail produce a very short travel time just by using, primarily, gravity.

 

[egribble]

To get to Mars cheaper and faster to save time and open up new mission windows, scientists say there's an easy shortcut: fly by Venus on the way.

Astronauts bound for Mars should swing by Venus first, scientists say : Read more

The primary reason for not taking this path is radiation. Solar radiation is a nightmare once you are beyond the Van Allen Belts. Taking people even closer to the sun is dangerous, there is only one realistic direction, outwards away from that nuclear furnace.

 

[Lovethrust]

The primary reason for not taking this path is radiation. Solar radiation is a nightmare once you are beyond the Van Allen Belts. Taking people even closer to the sun is dangerous, there is only one realistic direction, outwards away from that nuclear furnace.

The minor amount of extra solar radiation would be more than compensated for by shorter stays on Mars, notto mention the option of an abort to Earth not available for Mars direct.

 

[funkpoppy]

Gaetano Crocco proposed a Venus-boost-to-Mars mission in 1956. Someone is borrowing heavily and not giving credit where it is due.

 

[Helio]

The minor amount of extra solar radiation would be more than compensated for by shorter stays on Mars, notto mention the option of an abort to Earth not available for Mars direct.

Yes, the shorter sailing time the less the risk of being caught in a storm (flares). The serious radiation events come from flares and CMEs. Spacecraft have safe areas that have extra shielding from such events, but the less time stuck in these areas the better.

 

[Helio]

Gaetano Crocco proposed a Venus-boost-to-Mars mission in 1956. Someone is borrowing heavily and not giving credit where it is due.

That's not surprising, but I hope credit is given to those who demonstrated feasibility.

 

[Torbjorn Larsson]

The year long travel times suits slow crawl NASA, modern interplanetary travel technology not so much - you want to reach Mars within 3-6 months to minimize travel time and radiation dose.

And on the balance, the white paper review covers decades of these types of deliberations.

The minor amount of extra solar radiation would be more than compensated for by shorter stays on Mars, notto mention the option of an abort to Earth not available for Mars direct.

That is the problem, since Starship proposes to start under ground colonization - rare returns.

The abort option is limited - a Starship flotilla has continuous backups (and return from Mars) instead.

Gaetano Crocco proposed a Venus-boost-to-Mars mission in 1956. Someone is borrowing heavily and not giving credit where it is due.

It's a white paper review, so they mention early NASA reviews and you have to dig some more to see if Crocco is not covered.

 

[Helio]

I pulled out my copy of The Real Book About Space Travel, 1952, Hal Goodwin. He gives Von Braun's plan presented to the Second International Congress of Astronautics in London, 1951.

Von Braun’s plan for travel to Mars:

♦ Huge "three step" ships would use over 500 million tons of fuel for 950 trips to a space platform.
♦ They would deliver 36,600 tons of fuel for the trip.
♦ 70 people would be in space.
♦ They would be supplied with several hundred tons of supplies and equipment.
♦ They would build 10 ships in space. The ships would probably not look like comic book ships but more like globe-type structures framed together.
♦ Braun called the ships “orbit to orbit ships" since they left Earth’s orbit and would remain in Mars' orbit serving as space stations, “perhaps next to Phobos.”
♦ Three large-winged ships would be used to land on Mars, carrying 50 astronauts to Mars surface.
♦ After about 400 days, two ships would return to the orbit-to-orbit ships.
♦ Total time would be 2 years, 239 days.
♦ The most dangerous part would be entering Earth’s atmosphere, where a series of “braking ellipses” would slow the ships and give them cooling time between each braking event.

 

[StarShipTrooper]

To get to Mars cheaper and faster to save time and open up new mission windows, scientists say there's an easy shortcut: fly by Venus on the way.

Astronauts bound for Mars should swing by Venus first, scientists say : Read more

Correct me if I'm wrong, Venus is in the opposite direction from Mars, what does flying by Venus do except increase the gravitational force exerted on a spacecraft that needs to go in another direction? Mars is in the opposite direction. We could use, at the right time, the gravitational force from Venus to take us to Mars but the trip would be much longer than it would be if we just flew to Mars after initially exploiting Earth's gravity.

I am really interested in hearing an explanation about this. There is an appropriate time in the orbits of all planets in our solar systems to use all available sources of gravity. I am all ears to anyone who wishes to jump into this thread, and please do!

 

[Helio]

Correct me if I'm wrong, Venus is in the opposite direction from Mars, what does flying by Venus do except increase the gravitational force exerted on a spacecraft that needs to go in another direction? Mars is in the opposite direction. We could use, at the right time, the gravitational force from Venus to take us to Mars but the trip would be much longer than it would be if we just flew to Mars after initially exploiting Earth's gravity.

Yes, and the article seems to agree that the trip itself would take longer. But without Venus we have to wait for Earth to go from one opposition with Mars to the next, and that's more than one Earth year. So it gives more windows of travel opportunity for space-farers, which would be helpful, especially in an emergency.

They argue also that it would take less fuel. As a kid with a bike, we lived in hills that allowed us to cover a lot of distance by going down one hill then up the next with little effort. Venus serves somewhat like this, but it's more of a sling shot analogy since its orbital speed is utilized as the ship comes from behind it.

 

[richWorld]

The fastest spacecraft ever to leave Earth (or escape it's influence) was the New Horizons probe to Pluto. It left the Earth at over 36000 mph using the never before used Atlas V-551 which has an added third stage and five SRBs. It passed Jupiter about a year after launch. So their solution was to take what exits and expand it. Obviously this won't help our much more massive Mars bound craft but were or are we thinking of this as we plan to send humans to Mars and beyond or will they build a whole new launch system again and again.