This picture still blows me away, hours later.... I made some rough estimates of the tank diameter, using the people. (who also are of unknown height but the taller ones are likely ~6ft). Taking into account the perspective distortion of a wide angle lens, this tank is at least 10m wide. So since the geometry matches the spacecraft schematic, this could actually be a full size 12m diameter LOX tank for the spacecraft!
Quote from: Jim on 09/27/2016 07:31 pmGoing to have huge environmental and health problems if one blows ups or burns on the padAnd would have the largest fatalities in spaceflight history.
Going to have huge environmental and health problems if one blows ups or burns on the pad
It sounds like its the actual tank for the initial ship that they plan on using for testing.
Robert Zubrin post on Elon's talk: https://www.facebook.com/robert.zubrin.1/posts/1799839760231952Overall favourable with this caveat:Quote[...]The key thing I would change is his plan to send the whole trans Mars propulsion system all the way to Mars and back. Doing that means it can only be used once every four years. Instead he should stage off of it just short of Earth escape. Then it would loop around back to aerobrake into Earth orbit in a week, while the payload habitat craft with just a very small propulsion system for landing would fly on to Mars.[...]
[...]The key thing I would change is his plan to send the whole trans Mars propulsion system all the way to Mars and back. Doing that means it can only be used once every four years. Instead he should stage off of it just short of Earth escape. Then it would loop around back to aerobrake into Earth orbit in a week, while the payload habitat craft with just a very small propulsion system for landing would fly on to Mars.[...]
Quote from: Space Ghost 1962 on 09/27/2016 09:35 pmQuote from: Jim on 09/27/2016 07:31 pmGoing to have huge environmental and health problems if one blows ups or burns on the padAnd would have the largest fatalities in spaceflight history.Who cares? Hundreds of people die each year in plane crashes and millions in automobile accidents. That doesn't stop aviation, let alone stop people from driving cars. Even the few fatalities in HSF so far have not stopped HSF.Are accidents and fatalities going to happen? Absolutely! Will this stop people from going places? H*ll no! It never has, and it never will.
Astonished. You get to ask ONE question to EM, the day of his LIFE speech on Mars. and what's your pick? toilets?#speechless.
Who cares? Hundreds of people die each year in plane crashes and millions in automobile accidents. That doesn't stop aviation, let alone stop people from driving cars. Even the few fatalities in HSF so far have not stopped HSF.Are accidents and fatalities going to happen? Absolutely! Will this stop people from going places? H*ll no! It never has, and it never will.
Quote from: FutureSpaceTourist on 09/28/2016 08:51 amRobert Zubrin post on Elon's talk: https://www.facebook.com/robert.zubrin.1/posts/1799839760231952Overall favourable with this caveat:Quote[...]The key thing I would change is his plan to send the whole trans Mars propulsion system all the way to Mars and back. Doing that means it can only be used once every four years. Instead he should stage off of it just short of Earth escape. Then it would loop around back to aerobrake into Earth orbit in a week, while the payload habitat craft with just a very small propulsion system for landing would fly on to Mars.[...]Zubrin makes a good point.
Quote from: Impaler on 09/28/2016 07:24 amQuote from: Space Ghost 1962 on 09/28/2016 06:46 amQuote from: pippin on 09/28/2016 04:43 amQuote from: Space Ghost 1962 on 09/28/2016 04:41 amQuote from: pippin on 09/28/2016 03:17 amHm... whole fleet but only one or two pads. That means months of loiter time...Keep in mind the high cadence implied. If daily and a hundred in fleet, two pads could handle it in a few months.If the top off tanker load also brings crew, your loiter is 50 days, assuming all depart at start of MOI window. Now add a few days of bad weather per year and a few other delays and you've got months of loiter time, don't you?That's pretty much what I said.What if I've severely underestimated his launch rate. What if its many times a day, like aircraft at a airport? Considerably different result - your 50+ days could drop to less than a week.The synod of 780 days means that 6000 launches to prepare a 1000 ship fleet would come out to 7.6 per day, if the turn around time is truly airplane like, and the launch site is supplied by an LNG tanker ship every day it's not inconceivable to get that kind of launch cadence out of the two sites proposed. No one would chose to live withing 100 miles of thouse sites at that kind of noise mind you. More likely a once a day launch cadence seems more realistic so 8 launch pads perhaps spread over 3-4 sites.The problem is getting all the passengers into LEO just prior to the mars launch window opening, if all the tankers have been launched and filled and 1000 full tankers are in orbit waiting to offload to 1000 manned ships then just the final 1000 launches need to be manned. But that would still takes 1/6th of the synod that's 130 days which is far too long.A possible solution is to launch the actual mars bound ships empty of passengers, fill them with propellant first and then use a high capacity manned vehicle with people crammed in like coach class airliners and immediately rendezvous with a series of ships unloading a portion of the passengers at each one then landing back on Earth to do it again. If a 4 to 1 ratio can be established then it only takes about 30 days to transport everyone into LEO.And in reality the launch window to mars at conjunction lasts about a month, so each ship can depart as soon as it's loaded and their would be no loitering of passengers in LEO other then the time it takes for each high capacity ship to transfer it's passengers. If that takes 3 days then each high capacity ship can be used 10 times during the window, which would work out to just 25 such ships being needed, a tiny number compared to the huge fleet being imagined, and as these ships stay at Earth they can probably be used for LEO or LUNAR shuttling flights the rest of the time as their interiors are more suited to trips of that duration anyways.The 1000 ships idea could be decades down the line. Make it 100 ships and that would perhaps be more realistic in the medium term, in my view.
Quote from: Space Ghost 1962 on 09/28/2016 06:46 amQuote from: pippin on 09/28/2016 04:43 amQuote from: Space Ghost 1962 on 09/28/2016 04:41 amQuote from: pippin on 09/28/2016 03:17 amHm... whole fleet but only one or two pads. That means months of loiter time...Keep in mind the high cadence implied. If daily and a hundred in fleet, two pads could handle it in a few months.If the top off tanker load also brings crew, your loiter is 50 days, assuming all depart at start of MOI window. Now add a few days of bad weather per year and a few other delays and you've got months of loiter time, don't you?That's pretty much what I said.What if I've severely underestimated his launch rate. What if its many times a day, like aircraft at a airport? Considerably different result - your 50+ days could drop to less than a week.The synod of 780 days means that 6000 launches to prepare a 1000 ship fleet would come out to 7.6 per day, if the turn around time is truly airplane like, and the launch site is supplied by an LNG tanker ship every day it's not inconceivable to get that kind of launch cadence out of the two sites proposed. No one would chose to live withing 100 miles of thouse sites at that kind of noise mind you. More likely a once a day launch cadence seems more realistic so 8 launch pads perhaps spread over 3-4 sites.The problem is getting all the passengers into LEO just prior to the mars launch window opening, if all the tankers have been launched and filled and 1000 full tankers are in orbit waiting to offload to 1000 manned ships then just the final 1000 launches need to be manned. But that would still takes 1/6th of the synod that's 130 days which is far too long.A possible solution is to launch the actual mars bound ships empty of passengers, fill them with propellant first and then use a high capacity manned vehicle with people crammed in like coach class airliners and immediately rendezvous with a series of ships unloading a portion of the passengers at each one then landing back on Earth to do it again. If a 4 to 1 ratio can be established then it only takes about 30 days to transport everyone into LEO.And in reality the launch window to mars at conjunction lasts about a month, so each ship can depart as soon as it's loaded and their would be no loitering of passengers in LEO other then the time it takes for each high capacity ship to transfer it's passengers. If that takes 3 days then each high capacity ship can be used 10 times during the window, which would work out to just 25 such ships being needed, a tiny number compared to the huge fleet being imagined, and as these ships stay at Earth they can probably be used for LEO or LUNAR shuttling flights the rest of the time as their interiors are more suited to trips of that duration anyways.
Quote from: pippin on 09/28/2016 04:43 amQuote from: Space Ghost 1962 on 09/28/2016 04:41 amQuote from: pippin on 09/28/2016 03:17 amHm... whole fleet but only one or two pads. That means months of loiter time...Keep in mind the high cadence implied. If daily and a hundred in fleet, two pads could handle it in a few months.If the top off tanker load also brings crew, your loiter is 50 days, assuming all depart at start of MOI window. Now add a few days of bad weather per year and a few other delays and you've got months of loiter time, don't you?That's pretty much what I said.What if I've severely underestimated his launch rate. What if its many times a day, like aircraft at a airport? Considerably different result - your 50+ days could drop to less than a week.
Quote from: Space Ghost 1962 on 09/28/2016 04:41 amQuote from: pippin on 09/28/2016 03:17 amHm... whole fleet but only one or two pads. That means months of loiter time...Keep in mind the high cadence implied. If daily and a hundred in fleet, two pads could handle it in a few months.If the top off tanker load also brings crew, your loiter is 50 days, assuming all depart at start of MOI window. Now add a few days of bad weather per year and a few other delays and you've got months of loiter time, don't you?That's pretty much what I said.
Quote from: pippin on 09/28/2016 03:17 amHm... whole fleet but only one or two pads. That means months of loiter time...Keep in mind the high cadence implied. If daily and a hundred in fleet, two pads could handle it in a few months.If the top off tanker load also brings crew, your loiter is 50 days, assuming all depart at start of MOI window.
Hm... whole fleet but only one or two pads. That means months of loiter time...
I raised a question last week on a related thread about the cost advantages of launching tankers from Mars - to Earth orbit - instead of launching them from Earth itself. Considering Mars's shallower gravity well, would it not require less energy to get fuel from Mars to Earth orbit than from Earth's surface to Earth orbit?
Quote from: Lar on 09/27/2016 10:51 pmI admit that I'm a little stressed about only 3 legs. I worry about tipping over. The squatness helps but still.Do 4 legs make it more stable? As shown on one the the F9 landings if one of the 4 legs collapses the rocket tips over. With less legs the odds are lower
I admit that I'm a little stressed about only 3 legs. I worry about tipping over. The squatness helps but still.
My personal opinion is SpaceX are too gung ho and they believe too much in themselves.
Quote from: M.E.T. on 09/28/2016 08:12 amSo if we look at non-Mars related industrial purposes for a moment, how does the BFS's cargo bay compare to that of the Space Shuttle, for example? How many times bigger is it?If you had this system, how much cheaper would it have been to build the International Space Station? Would a handful of launches have been sufficient to put the entire station into orbit?I estimate 670 cubic meters of un-pressurized cargo bay, that's compares to about 300 for the shuttle, and given that it looks to be divided into 2 decks of 3 meter height each and has small doors for access their is no useful LEO construction can be done with this the way the ISS was built, and I'm having trouble seeing how you get useful habitats that can be used on mars surface either. The vehicle has the mass margin to lift the ISS in almost one go, but not the volume.
So if we look at non-Mars related industrial purposes for a moment, how does the BFS's cargo bay compare to that of the Space Shuttle, for example? How many times bigger is it?If you had this system, how much cheaper would it have been to build the International Space Station? Would a handful of launches have been sufficient to put the entire station into orbit?
Quote from: Coastal Ron on 09/28/2016 12:37 amI understand the desire to see an entire plan laid out, but since we know that the cost of GETTING to Mars is a significant barrier to GOING to Mars, isn't it significant that Musk is proposing a transportation system that seems to solve that? I would agree that the portion of the iceberg above the surface is significant. I find the narrow focus on that portion disappointing, that's all.Quote Demanding Musk solve all the problems before presenting the solution to the first barrier is asking a lot I think...I make no demands on Musk. He can do as he pleases. I just find it amazing that he is embarking on a $10 billion/10 year program on just the bare hope that all the other pieces will fall into place at the right time.QuoteI think you expected too much. That much is obvious.QuoteSpaceX is a transportation provider, and that's what they plan on sticking to. But a transportation provider should have some idea to whom he is providing transportation. This is the ultimate "build it and they will come" gamble.Quote This presentation was a call for people to step forward and help.I saw it more as a $10 billion leap of faith that some people will step forward and help. We'll see who answers the call. It's his money...
I understand the desire to see an entire plan laid out, but since we know that the cost of GETTING to Mars is a significant barrier to GOING to Mars, isn't it significant that Musk is proposing a transportation system that seems to solve that?
Demanding Musk solve all the problems before presenting the solution to the first barrier is asking a lot I think...
I think you expected too much.
SpaceX is a transportation provider, and that's what they plan on sticking to.
This presentation was a call for people to step forward and help.