On Apr/17/2017 at 6:07 PM, JF Mezei wrote :
On 2017-04-17 13:07, Fred J. McCall wrote:

That article had a link to a NASA web page which describes its concept
for Mars. That page does not paint Orion/SLS as sending man to Mars.


Then you must not have read it very carefully. You think they're
going to get there on the wings of butterflies, perhaps?


I was refering to this:
https://www.nasa.gov/feature/deep-sp...t-destinations

(It was linked to in the artciel your refered to).

It calls ISS-2 "Deep Space Gateway".

##
build a crew tended spaceport in lunar orbit within the first few
missions that would serve as a gateway to deep space
##

##
For those destinations farther into the solar system, including Mars,
NASA envisions a deep space transport spacecraft. This spacecraft would
be a reusable vehicle that uses electric and chemical propulsion

In an earlier post, you asked about the fuel impact of doing assembly
in Lunar orbit vs in LEO. I had replied that it is cheaper to do your
acceleration low in the gravity well, meaning your better in LEO,
because of the Oberth effect. Well, if electric propulsion is used,
that's another story. Because electric propulsion can be very weak
but very efficient. So you might not be able to do all your acceleration
low in the gravity well, but the very high efficiency of electric
propulsion can compensate for the gravity loss of not using the Oberth
effect.

So if electric propulsion is used, building your spaceship in Lunar
orbit might make sense. I'm saying might, not does, because it depends
on many details. But there can be some mission architectures were
building in Lunar orbit is the best way to go.

and
would be specifically designed for crewed missions to destinations such
as Mars. The transport would take crew out to their destination, return
them back to the gateway, where it can be serviced and sent out again.
##

It odesn't mention SLS used to get to mars, it mentions its cargo
capacity to that Deep Space Gateway.


Alain Fournier