What kind of trajectory can give a 100 day flight time to Mars? Can that be done with a single chemical rocket burn or would it be with a chemical rocket boost and SEP constant thrust?
Quote from: RonM What kind of trajectory can give a 100 day flight time to Mars? Can that be done with a single chemical rocket burn or would it be with a chemical rocket boost and SEP constant thrust?I'd say that's a pretty pertinent question, although from the last thread I don't think RonM got an answer from anybody. I'm rather desperate to know the same, anybody got an idea?
Quote from: The Amazing Catstronaut on 02/16/2015 12:21 pmQuote from: RonM What kind of trajectory can give a 100 day flight time to Mars? Can that be done with a single chemical rocket burn or would it be with a chemical rocket boost and SEP constant thrust?I'd say that's a pretty pertinent question, although from the last thread I don't think RonM got an answer from anybody. I'm rather desperate to know the same, anybody got an idea?Have a look at Nasa's Trajectory Browser. http://trajbrowser.arc.nasa.gov/I was surprised to find that there are 128 days trajectories for just a bit over 6 km/s delta v.
From this video, MCT will be about 100x the size of an SUV.
But there's evidence that SpaceX is now considering SEP as part of their MCT architecture (based on comments by Shotwell), although you don't get the impression that they've decided on it, yet.
So we are looking at solar-electric propulsion, I think we are go to look at some other interesting propulsion (in-space propulsion) technologies, but our lift of both from the surface of Mars as well as Earth will probably be liquid oxygen and methane
QuoteSo we are looking at solar-electric propulsion, I think we are go to look at some other interesting propulsion (in-space propulsion) technologies, but our lift of both from the surface of Mars as well as Earth will probably be liquid oxygen and methane
Quote from: MikeAtkinson on 02/16/2015 05:46 pmQuoteSo we are looking at solar-electric propulsion, I think we are go to look at some other interesting propulsion (in-space propulsion) technologies, but our lift of both from the surface of Mars as well as Earth will probably be liquid oxygen and methaneI'm more interested in what these might be.
http://forum.nasaspaceflight.com/index.php?topic=36313.0
Quote from: SleeperService on 02/16/2015 05:54 pmhttp://forum.nasaspaceflight.com/index.php?topic=36313.0Not likely to be an EM drive in my opinion - I am skeptical that they work, even if they do work the reported thrust levels are too low (by several orders of magnitude) to be useful for a Mars transit.
Agreed. However the Chinese researchers and Shawyer have shown much greater thrust/KW...The jury is out at the mo, but I think it is this line of work that comes under the 'interesting propulsion' description.
Quote from: SleeperService on 02/16/2015 06:22 pmAgreed. However the Chinese researchers and Shawyer have shown much greater thrust/KW...The jury is out at the mo, but I think it is this line of work that comes under the 'interesting propulsion' description.For now, we should dismiss anything more exotic than solar electric propulsion technologies, which have already been demonstrated and proven in space flight.I don't think SpaceX is going to design anything around technologies that have not already been thoroughly researched. When you want to keep costs low, unproven technology is a liability. Technology that doesn't actually exist is unthinkable.