Posted on 12/21/2020 9:34:04 PM PST by BenLurkin
The biggest challenge (or constraint) is the mass of the payload (spacecraft, people, fuel, supplies etc) needed to make the journey.
The payload mass is usually just a small percentage of the total mass of the launch vehicle.
For example, the Saturn V rocket that launched Apollo 11 to the Moon weighed 3,000 tons.
But it could launch only 140 tons (5% of its initial launch mass) to low Earth orbit, and 50 tons (less than 2% of its initial launch mass) to the Moon.
Mass constrains the size of a Mars spacecraft and what it can do in space. Every maneuver costs fuel to fire rocket motors, and this fuel must currently be carried into space on the spacecraft.
SpaceX's plan is for its crewed Starship vehicle to be refueled in space by a separately launched fuel tanker. That means much more fuel can be carried into orbit than could be carried on a single launch.
This saves a lot of fuel, but can result in missions that take years to reach their destinations. Clearly this is something humans would not want to do.
Both Earth and Mars have (almost) circular orbits and a maneuver known as the Hohmann transfer is the most fuel-efficient way to travel between two planets. Basically, without going into too much detail, this is where a spacecraft does a single burn into an elliptical transfer orbit from one planet to the other.
A Hohmann transfer between Earth and Mars takes around 259 days (between eight and nine months) and is only possible approximately every two years due to the different orbits around the Sun of Earth and Mars.
A spacecraft could reach Mars in a shorter time (SpaceX is claiming six months) but—you guessed it—it would cost more fuel to do it that way.
(Excerpt) Read more at phys.org ...
First Men on the Moon.
With that stuff.
Going to need something like a nuclear electric rocket. Not huge thrust, but constant and compact. Steady acceleration adds up over time.
They don’t come back... It’s a one way trip....
Build a long bridge.
If it can be promised to me that no Democrats or fake Republicans can ever go there, I will find a way.
Nurse:
“Hello? Hellooo?
“Perhaps you need another shot.”
(nurse injects, some grunting)
“There that should do it.”
(nurse walks to door, opens it)
“Sweet dreams. You bastard.”
(nurse closes door)
I remember now
I remember how it started
I can’t remember yesterday
I just remember doing what they told me
Told me
Told me
Told me
and make billionaires trillioniars in the process.
” ..and maybe we could start a fresh society without communists.”
You’d be dealing with humans still, and you’d end up with a Lord of the Flies situation.
We should not be bringing them back, make it a one way trip to set up the colony, sure, there will be casualties but plenty of people want to volunteer.
Dont have to be astronaunts, thats old thinking, these are pioneers setting up new human outposts.
Send 100, with resupply, they are expendable, we can send more next trip.
Why?
Simple. Don’t do it. Mars is frozen desert with no breathable atmoshere. It is distant death and supplying micro habitats for our kind are horrifically expensive.
Pow! To the Moon Alice- To the Moon!
just need a little bigger jackie gleeson-
I will be dead and gone by the time this sh*t happens, so yeah.....
That won’t work.
Not gonna happen anytime soon.
What are you going to do send people 2 at a time?
The bigger the ship the more difficult to leave Earth’s gravity.
They know this.....
In fact it's cold as Hell.
What?
[How to get people from Earth to Mars and safely back again]
1) Wait until Mars Attacks!
2) Play Slim Whitman records
3) Steal Martian spaceship while Martians explode to Slim Whitman
4) Fly to Mars!
5) Take many pictures including selfies
6) Fly back to Earth
7) Profit!
8) Easy-peasy
We aren’t going ANYWHERE...we’re all wearing masks, our elections are a disaster, and we can’t get the damn mail delivered. LOL at the former America.
There has to be many places I can use that!
Taxing the wealthy, of course.
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