Quote from: Robotbeat on 01/02/2017 06:37 amNot down-beat at all. Methane straight from the ground is ridiculously cheap right now in the US.And a ton of methane is about 15 MWh of energy though takes almost twice that in electricity to produce it, say 25MWh. Even with, like 2 cents per kWh, you're still looking at $500. But you also have capital cost of the electrolysis, etc.Biomethane wouldn't be cheaper than that.Perhaps not but that's on Earth. On Mars energy of any kind is going to be expensive. Even assuming the hulls can come back completely empty as an RPV/autopilot system they're still going to need a lot of propellant to get them back to Earth orbit.
Not down-beat at all. Methane straight from the ground is ridiculously cheap right now in the US.And a ton of methane is about 15 MWh of energy though takes almost twice that in electricity to produce it, say 25MWh. Even with, like 2 cents per kWh, you're still looking at $500. But you also have capital cost of the electrolysis, etc.Biomethane wouldn't be cheaper than that.
Quote from: john smith 19 on 01/02/2017 04:17 pmQuote from: Robotbeat on 01/02/2017 06:37 amNot down-beat at all. Methane straight from the ground is ridiculously cheap right now in the US.And a ton of methane is about 15 MWh of energy though takes almost twice that in electricity to produce it, say 25MWh. Even with, like 2 cents per kWh, you're still looking at $500. But you also have capital cost of the electrolysis, etc.Biomethane wouldn't be cheaper than that.Perhaps not but that's on Earth. On Mars energy of any kind is going to be expensive. Even assuming the hulls can come back completely empty as an RPV/autopilot system they're still going to need a lot of propellant to get them back to Earth orbit.Solar power is getting pretty cheap. There's ~half as much sunlight on Mars, sure, but I would BET you there's more average sunlight near the equator on some parts of Mars than most of northern Germany (consider that much of northern Germany gets less than half the sunlight as parts of the American Southwest and less than a THIRD the sunlight of parts of the Andes and Australia). And more consistent over the year, too, even taking into consideration dust storms (although that's less critical for our discussion here, which is about overall propellant production capability).Solar panels (not just cells but panels) are down to around 39 cents per Watt, now. Probably will keep falling to below 25 cents per Watt, especially for thin film. And thin film solar could be made ridiculously lightweight given the right substrate. So you could ship the cells to Mars cheaply on ITS and install them on a frame built on Mars out of local material. Vast fields of solar panels on Mars, placed with some sort of semi-automated machine like we plant and harvest crops on Earth or lay railroads.And nuclear power could be relatively cheap, too (assuming we have some local manufacturing capability... not super sophisticated necessarily). Worries about exposure are less critical since the whole surface is bathed in radiation, and land is basically free (IF you can get there). So it's possible you could build and run reactors cheaper on Mars (shipping only the sophisticated parts, not massive things like containment vessels which aren't needed on Mars and/or could be made locally anyway from meteoric iron) than you could in a highly developed country on Earth due to cost of land and radiation concerns. You could possibly use thorium-burning reactors (doesn't /have/ to be a sophisticated molten salt design, but I guess it could be) and only send basically raw thorium to Mars packed carefully.So it's not obvious that by the time any of this happens that power would be immensely expensive on Mars. Initial setup WILL be expensive, but once you have some ability to build simple structures on Mars, it could be relatively reasonable.
Hmm.I think it's pretty clear that SX should avoid doing anything nuclear related in 2017. I'm hopeful that NASA's work on the KiloPower project will deliver results that can be of use to SX. 5-10Kw seems a nice granular size for use in a variety of projects, on Mars, off Mars and en route to Mars. But SX getting into nuclear technology directly seems a very bad use of time and what would be very significant resources, for all the issues around the approaches to space nuclear systems. More positively if they want to meet the 2018 deadline for a Mars landing they will have to complete work on Red Dragon and I presume get it launched.
More positively if they want to meet the 2018 deadline for a Mars landing they will have to complete work on Red Dragon and I presume get it launched.
Quote from: Robotbeat on 01/02/2017 05:47 pmQuote from: john smith 19 on 01/02/2017 04:17 pmQuote from: Robotbeat on 01/02/2017 06:37 amNot down-beat at all. Methane straight from the ground is ridiculously cheap right now in the US.And a ton of methane is about 15 MWh of energy though takes almost twice that in electricity to produce it, say 25MWh. Even with, like 2 cents per kWh, you're still looking at $500. But you also have capital cost of the electrolysis, etc.Biomethane wouldn't be cheaper than that.Perhaps not but that's on Earth. On Mars energy of any kind is going to be expensive. Even assuming the hulls can come back completely empty as an RPV/autopilot system they're still going to need a lot of propellant to get them back to Earth orbit.Solar power is getting pretty cheap. There's ~half as much sunlight on Mars, sure, but I would BET you there's more average sunlight near the equator on some parts of Mars than most of northern Germany (consider that much of northern Germany gets less than half the sunlight as parts of the American Southwest and less than a THIRD the sunlight of parts of the Andes and Australia). And more consistent over the year, too, even taking into consideration dust storms (although that's less critical for our discussion here, which is about overall propellant production capability).Solar panels (not just cells but panels) are down to around 39 cents per Watt, now. Probably will keep falling to below 25 cents per Watt, especially for thin film. And thin film solar could be made ridiculously lightweight given the right substrate. So you could ship the cells to Mars cheaply on ITS and install them on a frame built on Mars out of local material. Vast fields of solar panels on Mars, placed with some sort of semi-automated machine like we plant and harvest crops on Earth or lay railroads.And nuclear power could be relatively cheap, too (assuming we have some local manufacturing capability... not super sophisticated necessarily). Worries about exposure are less critical since the whole surface is bathed in radiation, and land is basically free (IF you can get there). So it's possible you could build and run reactors cheaper on Mars (shipping only the sophisticated parts, not massive things like containment vessels which aren't needed on Mars and/or could be made locally anyway from meteoric iron) than you could in a highly developed country on Earth due to cost of land and radiation concerns. You could possibly use thorium-burning reactors (doesn't /have/ to be a sophisticated molten salt design, but I guess it could be) and only send basically raw thorium to Mars packed carefully.So it's not obvious that by the time any of this happens that power would be immensely expensive on Mars. Initial setup WILL be expensive, but once you have some ability to build simple structures on Mars, it could be relatively reasonable.All true, all good, one comment - Mars inclination is higher, so while consistent, solar power generation during winter is consistently low. But that's just a known consistent factor you just have to bring into account.For nuclear, I betcha legal costs on earth are higher than interplanetary transport costs...And hey, there's always Hydrino power.
I don't think they're likely to land a Dragon on Mars in 2018 if they don't launch FH a few times in 2017 and their chance of success will be higher if they can flight-test anything novel that will be on board the first RD, but there would be no reason to launch RD to Mars in 2017.Dinking around with the Ames trajectory browser, it looks like the next departure window is centered on May 2018, with minimal delta-V trajectories getting them there in December.
At best a 50:50 chance of making the 2018 date for Red Dragon. And then still just a 50% chance of success if it does launch in 2018.
Quote from: launchwatcher on 01/03/2017 12:24 amthe next departure window is centered on May 2018, with minimal delta-V trajectories getting them there in December.I had 2018 in my head as the landing date.
the next departure window is centered on May 2018, with minimal delta-V trajectories getting them there in December.
1) Launch the Iridium group without mishap on Jan 9th, or at least launch it in January2)Keep launching a payload a month from that pad for the rest of the year without mishap3)Launch an FH. 4)Finish work on the RD and get it flight ready for an FH launch.
(...)1. Agreed and the AMOS launch by end of January(...)
Quote from: john smith 19 on 01/06/2017 01:32 pm1) Launch the Iridium group without mishap on Jan 9th, or at least launch it in January2)Keep launching a payload a month from that pad for the rest of the year without mishap3)Launch an FH. 4)Finish work on the RD and get it flight ready for an FH launch.1. Agreed and the AMOS launch by end of January
2. The pace needs to be an average of one per every 3 weeks, if they want to hit 18 commercial / NASA launches.
3. Two launches of FH this year.
4. Doable if RD is in fact a re-used Dragon 2, i.e., the one from the pad abort, or an existing un-flown one; it doesn't have to be one for either the commercial cargo or crew contracts.
This thread:Four things SpaceX can do 2017:1) Do everything smart and good that they should do.2) Don't do things which are dumb that they shouldn't do.3) Be lucky.4) Don't be unlucky.
