Really? $150 million in new funding was announced in October, and they had been planning a flight for mid-December which didn't eventuate, but I can't find anything about it being cancelled. It's probably just been postponed. Again.
You don't need to be a superpower to experiment in this area. The University of Queensland here in Oz has the HyShot program which, despite a few teething problems, is producing world class results. The US has yet to see any results from its X-43 series. It will be interesting to see if India can live up to its own hype. Good luck to them.
Free libertarian handbook for the 1st person to sleep over-night on the surface of the moon.
That would be Al Bean and Pete Conrad during Apollo 12. They spent 2 days on the surface and slept a bit between moonwalks. Conrad dies in a motorcycle accident a while ago, but Bean is still around.
There is an interesting article here that discusses the use of either the OSP or a Soyuz capsule for Hubble maintenance. It would seem like a reasonable proposal, but it probably ain't gonna happen for political and "NASA cultural" reasons
Tunguska could have been bad, yes. It was also a rare event. Just becuase your next door neighbour wins the lottery does not mean that you are going to win it next week...
and it's been several tens of millions of years since the last asteroid.
...and just because you haven't won the lottery in the last thirty years of weekly entries does not improve your chances of winning it next week either.
Given that you are a rocket scientist, I can't believe that you don't understand probability, which leaves the impression that you are once again using Chicken Little tactics to overinflate the threat faced.
We should fully fund Spaceguard because it costs peanuts, has useful scientific return, and ya never know, maybe something will turn up to genuinely be worried about. But repeated and intellectually dishonest warnings about the sky falling in is no way to lobby for a human spaceflight program.
I for one don't fancy rolling the dice.
Possible translation: I can use the fact that there is a non-zero probability of this event occurring to inflate it into a scare campaign in order to push a personal agenda. Do you drive a car? Use air travel? Both far more likely methods of punching your clock, and I bet you don't spend shitloads of your own money trying to prevent the unlikely event of it occurring. The standard counterargument by the Chicken Littles is that a big asteroid strike would wipe out "all life on the planet" (hasn't actually done precisely that in any of the major strikes in the last few billion years, but what's one more hyperbolic distortion of the facts? Not that a world with algae as the highest lifeform would be a fun place) and thus is worthy of serious consideration. Probability-wise, I would rate the nuclear annihilation of humanity many, many orders of magnitude more likely than a comet strike. Should we be on the lookout for impact events? Most certainly. Should we demand billions of dollars be spent on it in the next decade because otherwise we will all definitely die? No.
Have you priced wood lately? It's INCREDIBLY expensive because of all the restrictions on logging.
Umm... I think it would be a lot cheaper to just create plantations here on Earth. It's not like we're going to run out of space to do that next week (consider all the cleared areas, for a start). Ditto for growing orbital crops in order to feed people down here. Mining and so on might get a look in, but the overheads on growing large amounts of biomass in space for export are not likely to make that economically feasible for a very, very long time. Try again when the space elevator is built.
On the other hand, using the biomass up there makes perfect sense. Saves having to haul it up the gravity well. I don't think we'll be seeing trees grown up there until we have enough infrastructure to enable us to start considering aesthetic factors, though.
One of NASA'a takes on why this may be technically feasible but impractical in reality hinges on the component of the ET that seems to have led to the recent tragedy: the foam insulation. It is rather fragile, and would be likely to shed lots of high-speed bits in orbit, creating a debris cloud that could make approaching it hazardous in the extreme. Even if you account for the fact that craft rendezvousing with it would approach the cloud at a small relative velocity, it's still a rather inconsiderate thing to do the the LEO environment. One suggested workaround would be to put the whole tank in a big sock to minimise such debris, but getting it over the outside of the tank would likely be orders of magnitude more difficult than any of the on-orbit construction that has taken place to date.
Also, the intenal pressure vessels are not equipped with human-sized ingress holes, so airlocks etc would have to be cut and welded to the structure whilst in orbit. This would be even more difficult than fitting the giant condom.
As for mining it for materials, to break it up would be hazardous as outlined in point 1, and there is currently no means of refining it into anything usable. To build an orbital facility able to process the thing would likely be so expensive that it would defeat the whole point of the exercise.
Crappy movies to the contrary, planet killer asteroids are a very big medium-term (next 200 years or so) threat.
According to who?
It seems to me that humanity has managed to get through six thousand odd years of recorded history without being annihilated by a big rock. Mega-extinction class impacts happen on a timescale of tens to hundreds of millions of years. Smaller city- or country-busters can be expected on a timescale of tens to hundreds of thousands of years. While I do think that programs such as Spacewatch are an excellent return on measly investment, I also think that people who declare that the cockroaches' day of dominance will happen next week are resorting to hyperbole because they really, really want to holiday on the Moon. By all means let's have a robust space exploration program, but try not to bruise the truth too much while lobbying for it. The genuine desire to explore is a better and more honest motivator than Chicken Little-driven overstatement.
1) Where would they put it? How would they attach it?
2) The satellite was designed for broadcast from geostationary orbit. The ISS wizzes around the Earth every 90 minutes or so. How would they point it? At what?
3) The bandwidth would be way, way more than could conceivably be used at the ISS for the foreseeable future (especially in the pissy "core complete" configuration). It would be a better idea to boost it to its intended orbit. See above for why that ain't happening.
1) The space shuttle fleet is fully booked for the foreseeable future, mostly on space station stuff.
2) It takes a lot of time to plan missions like you have proposed. The closest comparison would be the Hubble or SMM rescue missions. Spacewalkers would have to be deployed to attach a new upper stage. No provisions were made in the satellite design for such an operation, so they would have to invent ad hoc procedures. It may not even be possible at all. In the interim, the satellite would deorbit.
3) It would probably be so mindbogglingly dangerous and complicated that NASA would have a collective heart attack if you even suggested it to them.
4) It's not economical. The space shuttle costs in the region of $400 million per mission, with no guarantee that the rescue would be successful, due to the unprecedented difficulty of the operation.
Bamboozled by batteries? Better bulldust below!
on
Physics in the Movies
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· Score: 1
My personal sad fanboy take on the batteries crap was that Morpheus lied to Neo about the reason for keeping the humans around. I mean, it's Keanu. You could have told him that they were kept around because the air movement caused by humanity's collective breathing powered wind generators and he probably wouldn't have blinked.
I have a tendency to read too much into things, but there are hints of deeper, almost gnostic concepts in the movie. The battery nature of humanity could be viewed as a "willpower" battery used by the soulless machines, with "fusion" being a reference to human reproduction powering the continuation of the cycle. But maybe I should just stop smoking crack.
For a start, there are only four gyros in the Z1 truss. They can operate quite happily with three, and can get by nervously with two. If a third one fails, they have to resort to using rocket propellant from the Russian segment, which depletes their supplies a lot faster, which is a Bad Thing.
Second, each gyro weighs about 1100 pounds, including the assembly needed to secure it in the cargo bay of the Shuttle. The next two flights this year are carrying up big segments of the solar panel truss, and there just isn't enough room or weight to also carry the replacement gyro. This current flight is actually carrying a replacement wrist joint for the station robotic arm, but it only occupies about 2x2x2 feet, so it was easy to fit it into an otherwise one-third (or so) empty cargo bay.
Believe me, if they could get the gyro up there any earlier, they would.
No, it isn't. Azimuth and elevation are simple up-and-down, left-to-right figures, useless in finding an object if you move or even wait a while, like saying "go west 2km and then north 1 km" is not much use on Earth unless you know exactly where to start from. Right ascension and declination are the celestial version of latitude and longitude. They require an accurately aligned platform to be of any use, but once you've done it you can look up coordinates in a star atlas, point it at the sky, and bingo! RA and dec are also mounted on what is commonly called an equatorial platform, meaning that the platform is offset so it can turn in synch with the rotation of the earth via a single drive while pointing at the same object. I'm not sure, but I think it's the declination axis that does this. Altitude (elevation) and azimuth must both alter at varying rates to track a celestial object. That being said, equatorial mounts are much larger and more expensive than alt/az ones, so many big scopes nowadays use the simpler mount with computer control to do the tracking.
In short, both alt/az and equatorial (RA/dec) are pointing strategies, but RA/dec is a coordinate system.
Okay, I'll rise to the trollish bait, but just because some of the refutations are little better than the parent. The simple way to refute his statement without getting overly involved is simply to point out that by his logic we would not be able to see any stars or galaxies. Duh.
Second, there is no way that a craft with sufficient life support capacity for a human crew to travel to Mars is going to be capable of taking off and landing. It would go into orbit and deploy landers. I suspect you meant acceleration/deceleration instead of takeoff/landing. At least I hope you did.
Third, I strongly doubt that a ring is the form that would be chosen, as in order for it to produce a reasonable g-force it would either have to have a BIG diameter, or spin too fast for comfort. Far more likely would be to have a ship with a nuclear engine (the only way to fly!) and fuel tanks that can be separated from the crew compartment by a long cable. After acceleration, the cable could be paid out and the whole craft could be spun around the centre of gravity.
Now that I think of it, the ISS should have something like this
And while I'm wishing, I'd like a pony. Let's see if we can actually get the thing built to current specs before we get too carried away. Keep in mind that each can on the orbiting sixpack costs at least a billion dollars. How much do you think a spin section (particularly one with a large enough radius, see above) would cost?
The Tassie devil has been suggested as a host. The big advantage for the thylacine, and the reason why it will probably be the first successful recovery, is that it is a marsupial, which means it is born when it is basically still a foetus. This means that the host animal can be kept on immunosuppressants for the short duration of pregnancy without rejecting the embyo or getting too screwed up itself. Something like a mammoth, on the other hand, would need to be carried for 18 months inside what would end up being a very sick elephant.
as soon as they get the next module up for the ISS it's no longer an issue.
I assume you mean the centrifuge module, which was actually going to be the last module to be installed, not the next, and may not be launched at all thanks to the cutbacks. It was also not intended for human use: they'd find it a bit crowded. It's meant for samples that can be spun up to varying partial g-forces for experimental purposes. While it's neat, it ain't exactly the orbital Hilton.
Myself... I still ask WHY we aren't building the double spinning rings from 2001..
Oh, please. We can barely muster the political will to build the orbiting sixpack that we have now.
you only need solar power to build up a supply of hydrogen and oxygen to power you rockets and give inertia on the journey back.
Thou shalt not giveth inertia nor taketh it away. It is an innate property of matter related to its mass. I suspect you mean momentum, which still isn't quite putting it right, but is at least in the ballpark.
Cracking the water is the easy bit, because we know exactly what energy budget we need. The critical part, and one that will have to be tested by robot probes before we send people, is how easy it is to get the water out of the Martian soil. That's still an unknown, so we can't currently estimate how much energy would be required, how long it would take, or what area would need to be mined to provide the requisite amount of fuel. If you view his off-the-cuff comment in that light, then yes, there are a lot of on- and off-planet tests still to be done.
I would wager less than 10,000 years before a huge asteroid destroys life.
Err...yeah. Like the one 10,000 years ago when humanity was in the Mesolithic. Or the one 20,000 year ago when we were painting on cave walls. Or 30,000 years ago..
I think you'll find that mass extinction events occur on the order of tens of millions of years apart, not millennia. Every 10,000 years we might get one that would give us a bit of an economic downturn, to put it mildly, but not a global catastrophe like the KT event.
Slashdot Mirror
According to JPL's official calculation, Spirit (and presumably Mars) are currently 168,377,000 km away, or about 104,000,000 miles.
Really? $150 million in new funding was announced in October, and they had been planning a flight for mid-December which didn't eventuate, but I can't find anything about it being cancelled. It's probably just been postponed. Again.
You don't need to be a superpower to experiment in this area. The University of Queensland here in Oz has the HyShot program which, despite a few teething problems, is producing world class results. The US has yet to see any results from its X-43 series. It will be interesting to see if India can live up to its own hype. Good luck to them.
No, I'm...ahem.
SCO must have been sharing their crack pipe with this guy.
1) Assert ownership of valuable public asset.
2) Sue monstrous entity that can crush you like a bug.
3) ???
4) Profit!
Sleep over a lunar night? That's not sleeping, that's hibernating.
That would be Al Bean and Pete Conrad during Apollo 12. They spent 2 days on the surface and slept a bit between moonwalks. Conrad dies in a motorcycle accident a while ago, but Bean is still around.
There is an interesting article here that discusses the use of either the OSP or a Soyuz capsule for Hubble maintenance. It would seem like a reasonable proposal, but it probably ain't gonna happen for political and "NASA cultural" reasons
Tunguska could have been bad, yes. It was also a rare event. Just becuase your next door neighbour wins the lottery does not mean that you are going to win it next week...
...and just because you haven't won the lottery in the last thirty years of weekly entries does not improve your chances of winning it next week either.
Given that you are a rocket scientist, I can't believe that you don't understand probability, which leaves the impression that you are once again using Chicken Little tactics to overinflate the threat faced.
We should fully fund Spaceguard because it costs peanuts, has useful scientific return, and ya never know, maybe something will turn up to genuinely be worried about. But repeated and intellectually dishonest warnings about the sky falling in is no way to lobby for a human spaceflight program.
Possible translation: I can use the fact that there is a non-zero probability of this event occurring to inflate it into a scare campaign in order to push a personal agenda. Do you drive a car? Use air travel? Both far more likely methods of punching your clock, and I bet you don't spend shitloads of your own money trying to prevent the unlikely event of it occurring. The standard counterargument by the Chicken Littles is that a big asteroid strike would wipe out "all life on the planet" (hasn't actually done precisely that in any of the major strikes in the last few billion years, but what's one more hyperbolic distortion of the facts? Not that a world with algae as the highest lifeform would be a fun place) and thus is worthy of serious consideration. Probability-wise, I would rate the nuclear annihilation of humanity many, many orders of magnitude more likely than a comet strike. Should we be on the lookout for impact events? Most certainly. Should we demand billions of dollars be spent on it in the next decade because otherwise we will all definitely die? No.
Umm... I think it would be a lot cheaper to just create plantations here on Earth. It's not like we're going to run out of space to do that next week (consider all the cleared areas, for a start). Ditto for growing orbital crops in order to feed people down here. Mining and so on might get a look in, but the overheads on growing large amounts of biomass in space for export are not likely to make that economically feasible for a very, very long time. Try again when the space elevator is built.
On the other hand, using the biomass up there makes perfect sense. Saves having to haul it up the gravity well. I don't think we'll be seeing trees grown up there until we have enough infrastructure to enable us to start considering aesthetic factors, though.
One of NASA'a takes on why this may be technically feasible but impractical in reality hinges on the component of the ET that seems to have led to the recent tragedy: the foam insulation. It is rather fragile, and would be likely to shed lots of high-speed bits in orbit, creating a debris cloud that could make approaching it hazardous in the extreme. Even if you account for the fact that craft rendezvousing with it would approach the cloud at a small relative velocity, it's still a rather inconsiderate thing to do the the LEO environment. One suggested workaround would be to put the whole tank in a big sock to minimise such debris, but getting it over the outside of the tank would likely be orders of magnitude more difficult than any of the on-orbit construction that has taken place to date.
Also, the intenal pressure vessels are not equipped with human-sized ingress holes, so airlocks etc would have to be cut and welded to the structure whilst in orbit. This would be even more difficult than fitting the giant condom.
As for mining it for materials, to break it up would be hazardous as outlined in point 1, and there is currently no means of refining it into anything usable. To build an orbital facility able to process the thing would likely be so expensive that it would defeat the whole point of the exercise.
According to who?
It seems to me that humanity has managed to get through six thousand odd years of recorded history without being annihilated by a big rock. Mega-extinction class impacts happen on a timescale of tens to hundreds of millions of years. Smaller city- or country-busters can be expected on a timescale of tens to hundreds of thousands of years. While I do think that programs such as Spacewatch are an excellent return on measly investment, I also think that people who declare that the cockroaches' day of dominance will happen next week are resorting to hyperbole because they really, really want to holiday on the Moon. By all means let's have a robust space exploration program, but try not to bruise the truth too much while lobbying for it. The genuine desire to explore is a better and more honest motivator than Chicken Little-driven overstatement.
...Because you're bitching about duplicates of people bitching about duplicates. Other people got there before you.
Which means that I'm bitching about duplicates of people bitching about duplicates of people bitching about duplicates.
Or something like that.
1) Where would they put it? How would they attach it?
2) The satellite was designed for broadcast from geostationary orbit. The ISS wizzes around the Earth every 90 minutes or so. How would they point it? At what?
3) The bandwidth would be way, way more than could conceivably be used at the ISS for the foreseeable future (especially in the pissy "core complete" configuration). It would be a better idea to boost it to its intended orbit. See above for why that ain't happening.
Nice idea, but space doesn't quite work that way.
1) The space shuttle fleet is fully booked for the foreseeable future, mostly on space station stuff.
2) It takes a lot of time to plan missions like you have proposed. The closest comparison would be the Hubble or SMM rescue missions. Spacewalkers would have to be deployed to attach a new upper stage. No provisions were made in the satellite design for such an operation, so they would have to invent ad hoc procedures. It may not even be possible at all. In the interim, the satellite would deorbit.
3) It would probably be so mindbogglingly dangerous and complicated that NASA would have a collective heart attack if you even suggested it to them.
4) It's not economical. The space shuttle costs in the region of $400 million per mission, with no guarantee that the rescue would be successful, due to the unprecedented difficulty of the operation.
My personal sad fanboy take on the batteries crap was that Morpheus lied to Neo about the reason for keeping the humans around. I mean, it's Keanu. You could have told him that they were kept around because the air movement caused by humanity's collective breathing powered wind generators and he probably wouldn't have blinked.
I have a tendency to read too much into things, but there are hints of deeper, almost gnostic concepts in the movie. The battery nature of humanity could be viewed as a "willpower" battery used by the soulless machines, with "fusion" being a reference to human reproduction powering the continuation of the cycle. But maybe I should just stop smoking crack.
For a start, there are only four gyros in the Z1 truss. They can operate quite happily with three, and can get by nervously with two. If a third one fails, they have to resort to using rocket propellant from the Russian segment, which depletes their supplies a lot faster, which is a Bad Thing.
Second, each gyro weighs about 1100 pounds, including the assembly needed to secure it in the cargo bay of the Shuttle. The next two flights this year are carrying up big segments of the solar panel truss, and there just isn't enough room or weight to also carry the replacement gyro. This current flight is actually carrying a replacement wrist joint for the station robotic arm, but it only occupies about 2x2x2 feet, so it was easy to fit it into an otherwise one-third (or so) empty cargo bay.
Believe me, if they could get the gyro up there any earlier, they would.
RA and dec are also mounted on what is commonly called an equatorial platform, meaning that the platform is offset so it can turn in synch with the rotation of the earth via a single drive while pointing at the same object. I'm not sure, but I think it's the declination axis that does this. Altitude (elevation) and azimuth must both alter at varying rates to track a celestial object. That being said, equatorial mounts are much larger and more expensive than alt/az ones, so many big scopes nowadays use the simpler mount with computer control to do the tracking.
In short, both alt/az and equatorial (RA/dec) are pointing strategies, but RA/dec is a coordinate system.
Okay, I'll rise to the trollish bait, but just because some of the refutations are little better than the parent. The simple way to refute his statement without getting overly involved is simply to point out that by his logic we would not be able to see any stars or galaxies. Duh.
There are so many things wrong with this post.
First, it's not a starship if it's going to Mars.
Second, there is no way that a craft with sufficient life support capacity for a human crew to travel to Mars is going to be capable of taking off and landing. It would go into orbit and deploy landers. I suspect you meant acceleration/deceleration instead of takeoff/landing. At least I hope you did.
Third, I strongly doubt that a ring is the form that would be chosen, as in order for it to produce a reasonable g-force it would either have to have a BIG diameter, or spin too fast for comfort. Far more likely would be to have a ship with a nuclear engine (the only way to fly!) and fuel tanks that can be separated from the crew compartment by a long cable. After acceleration, the cable could be paid out and the whole craft could be spun around the centre of gravity.
And while I'm wishing, I'd like a pony. Let's see if we can actually get the thing built to current specs before we get too carried away. Keep in mind that each can on the orbiting sixpack costs at least a billion dollars. How much do you think a spin section (particularly one with a large enough radius, see above) would cost?
The Tassie devil has been suggested as a host. The big advantage for the thylacine, and the reason why it will probably be the first successful recovery, is that it is a marsupial, which means it is born when it is basically still a foetus. This means that the host animal can be kept on immunosuppressants for the short duration of pregnancy without rejecting the embyo or getting too screwed up itself. Something like a mammoth, on the other hand, would need to be carried for 18 months inside what would end up being a very sick elephant.
I assume you mean the centrifuge module, which was actually going to be the last module to be installed, not the next, and may not be launched at all thanks to the cutbacks. It was also not intended for human use: they'd find it a bit crowded. It's meant for samples that can be spun up to varying partial g-forces for experimental purposes. While it's neat, it ain't exactly the orbital Hilton.
Oh, please. We can barely muster the political will to build the orbiting sixpack that we have now.
Thou shalt not giveth inertia nor taketh it away. It is an innate property of matter related to its mass. I suspect you mean momentum, which still isn't quite putting it right, but is at least in the ballpark.
Cracking the water is the easy bit, because we know exactly what energy budget we need. The critical part, and one that will have to be tested by robot probes before we send people, is how easy it is to get the water out of the Martian soil. That's still an unknown, so we can't currently estimate how much energy would be required, how long it would take, or what area would need to be mined to provide the requisite amount of fuel. If you view his off-the-cuff comment in that light, then yes, there are a lot of on- and off-planet tests still to be done.
Err...yeah. Like the one 10,000 years ago when humanity was in the Mesolithic. Or the one 20,000 year ago when we were painting on cave walls. Or 30,000 years ago..
I think you'll find that mass extinction events occur on the order of tens of millions of years apart, not millennia. Every 10,000 years we might get one that would give us a bit of an economic downturn, to put it mildly, but not a global catastrophe like the KT event.