Both NASA, with public money, and SpaceX, through private investment, are developing very large rockets that will enable humans to fly into deep space. Both NASA and SpaceX ultimately want to send humans to Mars. A workshop like this could ultimately plant seeds that result in collaboration rather than competition in the years to come. That seems especially possible given the Trump administration's stated desire for NASA to work closely with commercial space companies like SpaceX and its innovative technologies, such as reusable launch vehicles.
If you have an operating BFS, which can be refuelled in orbit, you would have to be utterly insane to have anything to do with SLS on the same mission.At best it will launch a comparable payload to low earth orbit, for the least a dozen times more cash.With refuelling in orbit, you can throw several thousand tons of payload at Mars for the same price as one SLS launch. You can, if crew is not possible to launch on SLS, launch them on dragon.BFS would have to fail very, very badly in capability - to the point where it is little better than F9, or reusability/reliability to the point where it is worse than F9 block 5 for this to make sense.
My “what-if” above is not about whether using both is the best way to do it. I’m just speculating that it’s a likely scenario based on my belief that neither NASA and SpaceX are going to go at it alone and both BFR and SLS will be around in then 2020s.
Let's look at the proposed missions for SLS and BFR and compare their capabilities. Not internet fantasies of how they can be redesigned (although, that is fun).SLS will be able to send about 30 to 40 tons of payload towards Mars. FH (expendable) can send 16.8 tons of payload to Mars, but for sake of argument we'll assume NASA wants to use SLS.BFS will be able to land 150 tons on Mars.BFS looks like the obvious winner, but only if the destination is landing on Mars.SLS can send a payload including the rockets needed to put the payload in Mars orbit.So, a theoretical use of SLS would be NASA conducting a large mission in Mars orbit (say, exploring Phobos and Deimos). They would launch the uncrewed mission package to Mars orbit. Once in place, a BFS from the surface of Mars could launch with with the crew of the orbital mission and drop them off at the NASA vehicle. Then the BFS lands and can go back up to get the astros when they are done. BFS being used as a "Mars Uber" for the crew.
My “what-if” above is not about whether using both is the best way to do it. I’m just speculating that it’s a likely scenario based on my belief that neither NASA and SpaceX are going to go at it alone and both BFR and SLS will be around in the 2020s.
BFS looks like the obvious winner, but only if the destination is landing on Mars.SLS can send a payload including the rockets needed to put the payload in Mars orbit.
Quote from: Markstark on 08/06/2018 10:14 pmMy “what-if” above is not about whether using both is the best way to do it. I’m just speculating that it’s a likely scenario based on my belief that neither NASA and SpaceX are going to go at it alone and both BFR and SLS will be around in the 2020s.You have to remember that "NASA", the government agency that is made up of 17,000+ people across the country, does not get a vote on what it's goals are.Unless the President of the United States of America (whom NASA works for) and/or the Congress of the United States of America decide that it is in the best interests of our nation to send significant "stuff" to Mars, it won't matter what NASA does or does not want. And for the most part the U.S. Government doesn't care what SpaceX does outside of the borders of the U.S. either.So in order for Congress to provide funding for SLS launches that support activities on Mars, Congress first has to agree that there is a reason that merits the money.There is no reason today that Congress would spend large amounts of money to use the SLS for supporting activities on Mars, so if anyone wants that to happen a reason needs to be found. And soon, since it could take NASA a decade or more to build Mars hardware - and the SLS may not be around in 10 years unless there is a need for it.My $0.02
My post above should've read something to the effect "I think it is likely that NASA will be directed by congress to develop an architecture that utilizes both SLS and BFR". I believe this will happen because the United States Government will not be able to ignore the BFR in a few years and therefore it'll direct NASA to use it in conjunction with SLS (because they won't want SLS cancelled either due to jobs in cetain states).
Quote from: Markstark on 08/06/2018 11:26 pmMy post above should've read something to the effect "I think it is likely that NASA will be directed by congress to develop an architecture that utilizes both SLS and BFR". I believe this will happen because the United States Government will not be able to ignore the BFR in a few years and therefore it'll direct NASA to use it in conjunction with SLS (because they won't want SLS cancelled either due to jobs in cetain states).We're all space nerds here, and for the most part we all LOVE to do "what if" type stuff.However when it comes to the U.S. Government there has to be a "need" that can instigate and sustain large appropriations. To a certain extent Apollo, Shuttle and the ISS were all because of the Cold War, and Constellation was an emotional response to the Columbia Shuttle accident.The SLS development today seems to be justified by jobs, though let's not debate that here. However there are no operational programs that require the SLS so far - none that have been fully funded by Congress. So it would be easy to end the SLS if Congress were to debate it in the open (unlikely for a few years).You are suggesting that one "need" the U.S. Government may have is to somehow compete with SpaceX when their BFR becomes operational, and my opinion is that the U.S. Congress won't care about what SpaceX does. Mainly because the SLS is a government-only transportation system, and all payloads funded for it can be mandated to fly on it, so SpaceX won't be in competition with the SLS.Conversely, the U.S. Government is unlikely to feel threatened by SpaceX going to Mars. Or at least not for a couple of decades, which is how long I think it will be before it will be easier to live on Mars.However if our government did find a need, it would be quite a mismatch because:- SpaceX can develop flight-ready hardware far faster than NASA can.- The BFR will be far more capable than the SLS will be as far as how much cargo can be landed on Mars.- From what many of us can tell, the SLS will cost A LOT to fly, just for the rocket. Not sure how sustainable that will be.So NASA would certainly be a minority partner if they were to fly the SLS in conjunction with the BFR.
Quote from: RonM on 08/06/2018 10:54 pmBFS looks like the obvious winner, but only if the destination is landing on Mars.SLS can send a payload including the rockets needed to put the payload in Mars orbit.BFS can get somewhere north of 150 tons into Mars orbit and then land, with no modifications. (aerocapture, not entry).It can drop around 30 tons onto (or around) both Phobos and Deimos, and land nominally, or a several ton payload on (or around) each and return to LEO through aerocapture.
Killing SLS isn't enough. If NASA wants to afford a robust or even practical human space exploration program, the agency has to make fundamental changes in how it does everything in human space flight.
Do we have to have posts like this in every thread?
The idea is to come up with missions that would use both BFR and SLS.
Quote from: Markstark on 08/06/2018 10:14 pmMy “what-if” above is not about whether using both is the best way to do it. I’m just speculating that it’s a likely scenario based on my belief that neither NASA and SpaceX are going to go at it alone and both BFR and SLS will be around in then 2020s.Perhaps the least insane option would be for NASA to specify now that they wish to purchase fuel in orbit, for use at TMI/MOI.That would enable them to utilise whichever commercial vendor could supply that fuel and enable a much larger unitary capsule.
Quote from: RonM on 08/07/2018 03:41 amDo we have to have posts like this in every thread? You mean ones with obvious facts?
Quote from: RonM on 08/07/2018 03:41 amThe idea is to come up with missions that would use both BFR and SLS. It's fine to fantasize, but the way the agency does business, NASA can't make use of BFR, forget BFR and SLS.QuoteDo we have to have posts like this in every thread? Setting aside the repetitive launcher arguments, I have not seen a post about the costs of NASA's other HSF systems. (Although I'm sure some are buried somewhere.)Cost and budgetary realities suck but that doesn't mean they should be ignored, either.
Quote from: envy887 on 08/07/2018 04:08 amQuote from: RonM on 08/07/2018 03:41 amDo we have to have posts like this in every thread? You mean ones with obvious facts?Quote from: UltraViolet9 on 08/07/2018 04:10 amQuote from: RonM on 08/07/2018 03:41 amThe idea is to come up with missions that would use both BFR and SLS. It's fine to fantasize, but the way the agency does business, NASA can't make use of BFR, forget BFR and SLS.QuoteDo we have to have posts like this in every thread? Setting aside the repetitive launcher arguments, I have not seen a post about the costs of NASA's other HSF systems. (Although I'm sure some are buried somewhere.)Cost and budgetary realities suck but that doesn't mean they should be ignored, either.C'mon, guys, it's time for you to get real. SLS is a bad idea, but Congress is continuing to fund it. Your complaining about SLS and HSF funding on an internet forum doesn't change a thing. If you're that passionate about it, write your Congressman.
It might make more sense for NASA to put crew on Orion and use it to launch and return crew, meeting up with BFS in cis-lunar space.