Hey, I would *love* a cellphone that worked that way - provided it had 2-3x the raw capacity to deliver the same or higher effective battery life. With the added thickness, maybe I could even buy a phone as durable as the old flip-phones used to be. And it'd be nice if it actually could go down to "real zero" in a pinch, though obviously doing so on a regular basis would defeat the point.
Hardly. My car has been traveling at 67,000mph around the sun for years, and it can do 450,000mph around the galactic core. Though it runs little rough at those speeds, and regularly oscillates by almost 134,000mph.
> BUT that second stage will actually take a lot of work. 3 different types.
Maybe. But maybe not nearly so much as you'd expect. Consider - the passenger version could be, essentially, a sealed-closed cargo version. Just a giant open bay with fabric partitions arranged as desired, and any desired facilities (toiletries, air recycling, etc) bolted to the walls. Have everybody lash themselves into acceleration couches on the "floor" during launches and landings, and the rest of the time it's a spacious micro-gravity habitat.
Similarly, while a dedicated tanker would no doubt be handy, the job could initially be done, somewhat more expensively, by more numerous zero-payload cargo vessels. Adding supplemental tanks in the cargo bay might be possible as well, though at that point I suspect a dedicated cargo design might be easier. Though... supplemental tanks would let them benefit from standardized "working components", with the supplemental tanks only tied into the fuel system during transfer to the destination.
Quite - I tried to capture the timing in "launch for Mars by 2022", not get there.
And yeah - I could have been clearer that the revised BFR is intended to completely replace the Falcon 9 and Heavy - being cheaper on a per-launch basis, while having much greater payload capacity in terms of both mass and volume, to the point that the initial version of the BFR is projected to lower the per-pound launch cost to LEO 5-fold compared to the F9.
Plus the second stage is being designed to be able to, with orbital refueling around Earth, be able to land on the moon and return on a single tank of gas. As well as being able to land on Mars and, once refueled with locally-produced fuel, be able to make it back to Earth in a single stage with a payload of several (20?) tons. And be able to reach and land on the moons of the outer planets. And function as a suborbital transport on Earth, making most long journeys in under 30 minutes.
Basically a solid first step to a general purpose cargo-and-passenger mover. It should even be able to easily get the next-gen Bigelow BA2100 concept module into orbit - at least in terms of mass, and quite possibly in terms of volume - that's quite a large cargo bay.
> Otherwise, stop screwing around in port, and go out to open space. Why? There's very nearly literally *nothing* in space, it's just the void you have to cross to get anywhere. Asteroids are one obvious goal, lots of probably-fairly-concentrated raw materials, but mostly a pretty serious energy gradient to cross between.
The moon though is much closer, and offers limited gravity which would make early experiments in habitat construction a lot more convenient, as well as getting useful data on the health effects of low gravity versus known-problematic micro-gravity. And with a launch energy 22x lower than Earth, it would be a convenient place to acquire raw materials for orbital use. And it definitely has useful raw materials. To start with: rock. Several meters of rock make a pretty decent radiation shield - something you're going to want for any habitat outside Earth's protective magnetic field. And there's not really anything dramatically better for the job than rock - it's pretty much the mass that does it. And beyond that - Mars is basically made of mostly the same stuff as Earth, but it's geologically stable and has no ecosystem to pollute. We could follow a rich ore vein right down to the core of the planet if that's where it led, and dump toxic slag any old place we choose. Or sell it as radiation shielding - not like folks are going to be licking the outer shell of a space station. And if we can find convenient sources of C,H, and O then we can start synthesizing rocket fuel on the moon, which would be extremely useful for launches away from the Earth system, as well as for orbital traffic.
Yeah, we could try to leapfrog the moon entirely, go straight to micro-gravity habitats constructed in hollowed asteroids - but the moon makes for an excellent practice ground and way-station for Earth, which will continue to be relevant for a long time to come. Mars probably offers an easier path to a fully self-sufficient colony, with it's plentiful CO2 and water; but the moon almost certainly has more to offer Earth.
Not seeing it. Both feeds come in apparently focussed on the X-in-circle pad, both then veer down-right to the smaller X-only pad, and then the feed cuts away to the ground cam for touchdown.
Nope, you're right - I suspect somebody goofed on the feeds. The ground-cam clearly shows the near rocket landing on the bigger pad with the X inside a black circle, while the supposedly-different booster feeds show both landing on the same X-only pad (look at the buildings and roads in the last seconds to confirm it's actually the same pad)
Hmm, I'm not seeing any. Can you suggest a good timestamp? Early on I definitely saw some slow-moving debris that presumably fell off. And quite a few, bright, moderately fast-moving spots in the sky that I assume are other satellites.
It seems unlikely that outgassing would continue to throw off visible particles for long - but perhaps its orbital debris, or the results of collisions with such debris?
Won't do any good for anyone living here of course. It would take a huge fleet of BFRs to even keep up with population growth, especially since you can only launch every two years when the planets are in the right alignment. Plus, surviving on Mars is going to be immensely more difficult than surviving here, even in the absolute worst case climate scenarios.
The only reason climate change factors in at all, is because dealing with it may well sap our planetary resources and destabilize civilization to the point that interplanetary voyages become infeasible for many decades or centuries. The hope is that the colony becomes self-sufficient enough by then to be able to at least support its own interplanetary supply runs, and hopefully not absolutely need them.
I'd say the man-rating probably has more to do with carrying crew to the ISS. I'm not sure if NASA rating is even relevant to tourists - other than making the tourists more comfortable taking the risk.
I didn't see anything on that page to suggest NASA astronauts would be sent around the moon though - only to the ISS. Which makes sense - it would be rather pointless sending astronauts on a joyride around the moon - there's nothing they could do from orbit that unmanned satellites couldn't do better. I suspect that when NASA gets involved with manned moon missions again it will be either the proposed lunar space-station, or an actual moonbase - either of which will probably wait for the BFR with its massively increased payloads and planned ability to land on the Moon and return.
Indeed. In his latest September "Becoming a Multiplanet Species" speech (https://www.youtube.com/watch?v=3gFxiOR8UTw ) he said that construction of the first BFR would likely begin sometime this summer, with the optimistic ambition to be able to launch for Mars by 2022. And I think he said the plan was to entirely phase out Falcon 9 Block 5 production in the same timeframe to focus all available assets on the BFR, once enough Falcon 9s were built to satisfy forseeable demand for more conservative customers. And presumably to tide them through any early problems with the BFR.
If they're two feeds, they're from adjacent cameras on the same booster - which seems unlikely but not impossible. Where's the big black circle around the X on the landing pad? The ground cam clearly shows it, while both booster feeds clearly show a landing on the smaller X-only pad.
Nope. Focus on the big obvious bit: The ground cam clearly shows one booster landing on the bigger X-in-O pad, while both booster feeds show them landing on the smaller X-only pad.
Unfortunately, space itself is curved so that it still looks like a spheroid from any direction. You can only tell it's actually flat if you rapidly consume at least a week's supply of heavily spiked Kool-Aid and welcome the truth of Jebus-Under-The-Mountain into your heart.
Not at all - all the first-stage boosters use atmosphere-optimized engines that also work pretty well in space. But you'll notice that the single second-stage engine has a much larger bell, almost as large as those from the 9 first-stage engines combined - that's to optimize it for vacuum, which gives it a nice efficiency boost.
Basically, when designing the engine you have to pick the ambient pressure to optimize for - at that pressure it will burn as powerfully efficiently as possible, with effectiveness dropping as pressure changes in either direction - typically first stage engines are optimized for high power somewhere in the mid-to-high atmosphere, where they spend most of their time, while second stages are optimized for efficiency in full vacuum, since they don't need the raw power for liftoff, or to ever deal with an atmosphere.
I would assume there's also other optimizations that can be done to reduce efficiency falloff as pressure changes, but they almost certainly come at the expense of lower peak performance, so it's a balancing game.
As for trying to shape the first-stage plume by vectoring the engines - it might be possible, but is unlikely to show any gains. You need to keep two things in mind: 1: Any vectoring will, by necessity, be trading forward thrust for lateral vectoring effect 2: By the time the plume leaves the bell, it's basically stopped pushing the rocket forward - the rocket isn't actually propelled by the gasses shooting out the back - it's propelled by those by those rapidly-expanding gasses bouncing off the engine and bell as they expand. Once they leave the engine bell they no longer have any effect on the rocket at all (except possibly indirectly through fluid-dynamics effects on the surrounding atmosphere. Combine the two, and you'd have to pull off some pretty impressive fluid-dynamic miracles to even manage to break even. And even assuming you somehow managed that, it would almost certainly become impossible as you exceeded the speed of sound (aka the speed at which atmospheric disruptions can propagate)
Here's a good photo of what's basically going on - the bell is designed to contain the engine exhaust until it falls to ambient pressure and stops expanding, at which point no more work can be extracted from it. Too big, and the atmospheric pressure pushes the plume away from the bell, and you lose thrust to turbulence losses and wasted mass worth of useless bell. Too small, and the gas is still expanding when it leaves the bell, and you're throwing away all the work that could have still been done. Obviously in a vacuum that gas is going to keep expanding essentially forever, but the more it expands, the less remaining work it can do, and the faster the size (and mass) of a containing bell will increase. So at some point the diminishing returns just aren't worth pursuing any further. https://i.stack.imgur.com/cJ4e...
Let's be fair though - that first step into a new frontier was followed almost immediately by near-total retreat. This time the most important part of the engineering has been put front and center: the economics. We've just watched the most powerful rocket to fly in more than thirty years (by a factor of more than two) send an appreciable payload on an interplanetary trajectory, while landing all three first-stage boosters back on Earth (well, two of three, still waiting for confirmation on the core).
Yeah, it's only the fourth most powerful rocket ever launched, and is more than a factor of two behind the Saturn V, the most powerful ever launched. But it landed again, and can (presumably) fly again, bringing the cost down to a fraction of anything flown before.
This time when we go to space, we'll have a fair shot at staying there. And that is groundbreaking, in the farmer tilling his field sense. Going up turned out to be the easy part - coming down again in one piece, that's what will unlock space beyond Earth orbit as more than a research novelty.
Very exciting, though I couldn't help but notice that the supposedly different booster feeds were actually one duplicated feed. If you watch carefully at the buildings and roads you can see that they both show an identical landing on the bottom-right-most "X-only" pad, while the ground-level cam clearly shows the nearer one landing in the X-in-circle pad. You can even see circle-pad destined booster's flame at the top of both feeds.
I assume somebody goofed with the feeds, and didn't notice in all the excitement - they would have likely been nearly identical until the last few seconds.
True. But we're talking about documenting evidence, not taking award-winning artistic photos. For non-sensitive stuff I'd assume you'd turn off the encryption.
But yeah, buffering the last photo of two so you could at least verify proper focus, exposure, etc. would probably be relatively safe.
It is, but if it's the price of absolute security then perhaps it's worth sacrificing. I would assume it would be a toggleable option, so you'd still get review on vacation and artistic photos, just not of anything taken in encrypted mode. Which is probably generally going to be evidence, and held to much lower standards of artistic quality.
As an added bonus, if the review feature simply ignored encrypted photos then it would add a little obfuscation - guard seizes camera, only sees your vacation photos. No prompt for password or anything. Nothing looks suspicious and you're probably on your way.
And as AC says, you could potentially still review the last few photos that are still in RAM, which lets you still verify exposure, focus, etc.
There can be more than one traitor in an election. As a matter of fact, I suspect a close review of how many senators and representatives have sold out to enemies of the American people would reveal that traitors outnumber all other politicians combined, regardless of party affiliation.
What does Windows ME have to do with anything? Even at the time everybody recognized it as a bad joke. The only people to use it were the suckers that bought a new computer without first making sure it was running 98 instead.
Easy solution - put the encryption on a toggle feature. Don't need it, don't use it. Need it, it slows down how fast you can take photos while it's turned on, and probably makes those photos impossible to review, if not outright invisible without separate hardware.
Ram usually doesn't store a tell-tale for long without pretty extreme measures. And if you were concerned about it it wouldn't be terribly difficult to fill the entire memory with random noise whenever it's powered off - that should take care of it nicely.
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Hey, I would *love* a cellphone that worked that way - provided it had 2-3x the raw capacity to deliver the same or higher effective battery life. With the added thickness, maybe I could even buy a phone as durable as the old flip-phones used to be. And it'd be nice if it actually could go down to "real zero" in a pinch, though obviously doing so on a regular basis would defeat the point.
Hardly. My car has been traveling at 67,000mph around the sun for years, and it can do 450,000mph around the galactic core. Though it runs little rough at those speeds, and regularly oscillates by almost 134,000mph.
> BUT that second stage will actually take a lot of work. 3 different types.
Maybe. But maybe not nearly so much as you'd expect. Consider - the passenger version could be, essentially, a sealed-closed cargo version. Just a giant open bay with fabric partitions arranged as desired, and any desired facilities (toiletries, air recycling, etc) bolted to the walls. Have everybody lash themselves into acceleration couches on the "floor" during launches and landings, and the rest of the time it's a spacious micro-gravity habitat.
Similarly, while a dedicated tanker would no doubt be handy, the job could initially be done, somewhat more expensively, by more numerous zero-payload cargo vessels. Adding supplemental tanks in the cargo bay might be possible as well, though at that point I suspect a dedicated cargo design might be easier. Though... supplemental tanks would let them benefit from standardized "working components", with the supplemental tanks only tied into the fuel system during transfer to the destination.
Quite - I tried to capture the timing in "launch for Mars by 2022", not get there.
And yeah - I could have been clearer that the revised BFR is intended to completely replace the Falcon 9 and Heavy - being cheaper on a per-launch basis, while having much greater payload capacity in terms of both mass and volume, to the point that the initial version of the BFR is projected to lower the per-pound launch cost to LEO 5-fold compared to the F9.
Plus the second stage is being designed to be able to, with orbital refueling around Earth, be able to land on the moon and return on a single tank of gas. As well as being able to land on Mars and, once refueled with locally-produced fuel, be able to make it back to Earth in a single stage with a payload of several (20?) tons. And be able to reach and land on the moons of the outer planets. And function as a suborbital transport on Earth, making most long journeys in under 30 minutes.
Basically a solid first step to a general purpose cargo-and-passenger mover. It should even be able to easily get the next-gen Bigelow BA2100 concept module into orbit - at least in terms of mass, and quite possibly in terms of volume - that's quite a large cargo bay.
> Otherwise, stop screwing around in port, and go out to open space.
Why? There's very nearly literally *nothing* in space, it's just the void you have to cross to get anywhere. Asteroids are one obvious goal, lots of probably-fairly-concentrated raw materials, but mostly a pretty serious energy gradient to cross between.
The moon though is much closer, and offers limited gravity which would make early experiments in habitat construction a lot more convenient, as well as getting useful data on the health effects of low gravity versus known-problematic micro-gravity. And with a launch energy 22x lower than Earth, it would be a convenient place to acquire raw materials for orbital use. And it definitely has useful raw materials. To start with: rock. Several meters of rock make a pretty decent radiation shield - something you're going to want for any habitat outside Earth's protective magnetic field. And there's not really anything dramatically better for the job than rock - it's pretty much the mass that does it. And beyond that - Mars is basically made of mostly the same stuff as Earth, but it's geologically stable and has no ecosystem to pollute. We could follow a rich ore vein right down to the core of the planet if that's where it led, and dump toxic slag any old place we choose. Or sell it as radiation shielding - not like folks are going to be licking the outer shell of a space station. And if we can find convenient sources of C,H, and O then we can start synthesizing rocket fuel on the moon, which would be extremely useful for launches away from the Earth system, as well as for orbital traffic.
Yeah, we could try to leapfrog the moon entirely, go straight to micro-gravity habitats constructed in hollowed asteroids - but the moon makes for an excellent practice ground and way-station for Earth, which will continue to be relevant for a long time to come. Mars probably offers an easier path to a fully self-sufficient colony, with it's plentiful CO2 and water; but the moon almost certainly has more to offer Earth.
About the same as the difference between watching a supermodel walk past you, and having her stop and give you her number.
One just displays theoretical potential, the other offers a viable path forward.
Not seeing it. Both feeds come in apparently focussed on the X-in-circle pad, both then veer down-right to the smaller X-only pad, and then the feed cuts away to the ground cam for touchdown.
Nope, you're right - I suspect somebody goofed on the feeds. The ground-cam clearly shows the near rocket landing on the bigger pad with the X inside a black circle, while the supposedly-different booster feeds show both landing on the same X-only pad (look at the buildings and roads in the last seconds to confirm it's actually the same pad)
Hmm, I'm not seeing any. Can you suggest a good timestamp? Early on I definitely saw some slow-moving debris that presumably fell off. And quite a few, bright, moderately fast-moving spots in the sky that I assume are other satellites.
It seems unlikely that outgassing would continue to throw off visible particles for long - but perhaps its orbital debris, or the results of collisions with such debris?
Won't do any good for anyone living here of course. It would take a huge fleet of BFRs to even keep up with population growth, especially since you can only launch every two years when the planets are in the right alignment. Plus, surviving on Mars is going to be immensely more difficult than surviving here, even in the absolute worst case climate scenarios.
The only reason climate change factors in at all, is because dealing with it may well sap our planetary resources and destabilize civilization to the point that interplanetary voyages become infeasible for many decades or centuries. The hope is that the colony becomes self-sufficient enough by then to be able to at least support its own interplanetary supply runs, and hopefully not absolutely need them.
I'd say the man-rating probably has more to do with carrying crew to the ISS. I'm not sure if NASA rating is even relevant to tourists - other than making the tourists more comfortable taking the risk.
I didn't see anything on that page to suggest NASA astronauts would be sent around the moon though - only to the ISS. Which makes sense - it would be rather pointless sending astronauts on a joyride around the moon - there's nothing they could do from orbit that unmanned satellites couldn't do better. I suspect that when NASA gets involved with manned moon missions again it will be either the proposed lunar space-station, or an actual moonbase - either of which will probably wait for the BFR with its massively increased payloads and planned ability to land on the Moon and return.
Indeed. In his latest September "Becoming a Multiplanet Species" speech (https://www.youtube.com/watch?v=3gFxiOR8UTw ) he said that construction of the first BFR would likely begin sometime this summer, with the optimistic ambition to be able to launch for Mars by 2022. And I think he said the plan was to entirely phase out Falcon 9 Block 5 production in the same timeframe to focus all available assets on the BFR, once enough Falcon 9s were built to satisfy forseeable demand for more conservative customers. And presumably to tide them through any early problems with the BFR.
If they're two feeds, they're from adjacent cameras on the same booster - which seems unlikely but not impossible. Where's the big black circle around the X on the landing pad? The ground cam clearly shows it, while both booster feeds clearly show a landing on the smaller X-only pad.
Nope. Focus on the big obvious bit: The ground cam clearly shows one booster landing on the bigger X-in-O pad, while both booster feeds show them landing on the smaller X-only pad.
Absolutely!
Unfortunately, space itself is curved so that it still looks like a spheroid from any direction. You can only tell it's actually flat if you rapidly consume at least a week's supply of heavily spiked Kool-Aid and welcome the truth of Jebus-Under-The-Mountain into your heart.
Not at all - all the first-stage boosters use atmosphere-optimized engines that also work pretty well in space. But you'll notice that the single second-stage engine has a much larger bell, almost as large as those from the 9 first-stage engines combined - that's to optimize it for vacuum, which gives it a nice efficiency boost.
Basically, when designing the engine you have to pick the ambient pressure to optimize for - at that pressure it will burn as powerfully efficiently as possible, with effectiveness dropping as pressure changes in either direction - typically first stage engines are optimized for high power somewhere in the mid-to-high atmosphere, where they spend most of their time, while second stages are optimized for efficiency in full vacuum, since they don't need the raw power for liftoff, or to ever deal with an atmosphere.
I would assume there's also other optimizations that can be done to reduce efficiency falloff as pressure changes, but they almost certainly come at the expense of lower peak performance, so it's a balancing game.
As for trying to shape the first-stage plume by vectoring the engines - it might be possible, but is unlikely to show any gains. You need to keep two things in mind:
1: Any vectoring will, by necessity, be trading forward thrust for lateral vectoring effect
2: By the time the plume leaves the bell, it's basically stopped pushing the rocket forward - the rocket isn't actually propelled by the gasses shooting out the back - it's propelled by those by those rapidly-expanding gasses bouncing off the engine and bell as they expand. Once they leave the engine bell they no longer have any effect on the rocket at all (except possibly indirectly through fluid-dynamics effects on the surrounding atmosphere.
Combine the two, and you'd have to pull off some pretty impressive fluid-dynamic miracles to even manage to break even. And even assuming you somehow managed that, it would almost certainly become impossible as you exceeded the speed of sound (aka the speed at which atmospheric disruptions can propagate)
Here's a good photo of what's basically going on - the bell is designed to contain the engine exhaust until it falls to ambient pressure and stops expanding, at which point no more work can be extracted from it. Too big, and the atmospheric pressure pushes the plume away from the bell, and you lose thrust to turbulence losses and wasted mass worth of useless bell. Too small, and the gas is still expanding when it leaves the bell, and you're throwing away all the work that could have still been done. Obviously in a vacuum that gas is going to keep expanding essentially forever, but the more it expands, the less remaining work it can do, and the faster the size (and mass) of a containing bell will increase. So at some point the diminishing returns just aren't worth pursuing any further.
https://i.stack.imgur.com/cJ4e...
Yeah, I recall him saying that he'd consider the test flight a success if they just managed to get far enough away to avoid damaging the launch pad.
Let's be fair though - that first step into a new frontier was followed almost immediately by near-total retreat. This time the most important part of the engineering has been put front and center: the economics. We've just watched the most powerful rocket to fly in more than thirty years (by a factor of more than two) send an appreciable payload on an interplanetary trajectory, while landing all three first-stage boosters back on Earth (well, two of three, still waiting for confirmation on the core).
Yeah, it's only the fourth most powerful rocket ever launched, and is more than a factor of two behind the Saturn V, the most powerful ever launched. But it landed again, and can (presumably) fly again, bringing the cost down to a fraction of anything flown before.
This time when we go to space, we'll have a fair shot at staying there. And that is groundbreaking, in the farmer tilling his field sense. Going up turned out to be the easy part - coming down again in one piece, that's what will unlock space beyond Earth orbit as more than a research novelty.
Very exciting, though I couldn't help but notice that the supposedly different booster feeds were actually one duplicated feed. If you watch carefully at the buildings and roads you can see that they both show an identical landing on the bottom-right-most "X-only" pad, while the ground-level cam clearly shows the nearer one landing in the X-in-circle pad. You can even see circle-pad destined booster's flame at the top of both feeds.
I assume somebody goofed with the feeds, and didn't notice in all the excitement - they would have likely been nearly identical until the last few seconds.
True. But we're talking about documenting evidence, not taking award-winning artistic photos. For non-sensitive stuff I'd assume you'd turn off the encryption.
But yeah, buffering the last photo of two so you could at least verify proper focus, exposure, etc. would probably be relatively safe.
It is, but if it's the price of absolute security then perhaps it's worth sacrificing. I would assume it would be a toggleable option, so you'd still get review on vacation and artistic photos, just not of anything taken in encrypted mode. Which is probably generally going to be evidence, and held to much lower standards of artistic quality.
As an added bonus, if the review feature simply ignored encrypted photos then it would add a little obfuscation - guard seizes camera, only sees your vacation photos. No prompt for password or anything. Nothing looks suspicious and you're probably on your way.
And as AC says, you could potentially still review the last few photos that are still in RAM, which lets you still verify exposure, focus, etc.
There can be more than one traitor in an election. As a matter of fact, I suspect a close review of how many senators and representatives have sold out to enemies of the American people would reveal that traitors outnumber all other politicians combined, regardless of party affiliation.
What does Windows ME have to do with anything? Even at the time everybody recognized it as a bad joke. The only people to use it were the suckers that bought a new computer without first making sure it was running 98 instead.
Easy solution - put the encryption on a toggle feature. Don't need it, don't use it. Need it, it slows down how fast you can take photos while it's turned on, and probably makes those photos impossible to review, if not outright invisible without separate hardware.
Ram usually doesn't store a tell-tale for long without pretty extreme measures. And if you were concerned about it it wouldn't be terribly difficult to fill the entire memory with random noise whenever it's powered off - that should take care of it nicely.