The article only supplies about a quarter of the average daily American jingoism intake.
The thread for space cadets!
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The article only supplies about a quarter of the average daily American jingoism intake.
Winner
Diverse in Unity
Sceptical why? If the asteroid is small (I mean has a low enough mass) and we have enough time to prepare, I don't see why this shouldn't work.
Nukes in space don't generally do so much damage (no shockwave) as in the atmosphere. That's why they first want to create a cloud of dust and detonate the nuke inside it, so that more of the nuke's energy is applied directly to the asteroidal matter in order to provide an impulse to push it away from the collision orbit.
The problem with this is that unless you know precisely what the approaching object is like (its mass, what it is made of, what its internal structure is), you don't know what will happen. You can end up fracturing the asteroid into several large pieces, all of which will hit Earth anyway (that's one of the seven billion reasons why Armageddon sucked, BTW
).I guess a safe bet would be to use a really HUGELY powerful nuke (>100 Mt) and blow the asteroid into smithereens - particles no larger than pebbles. They'd still hit earth, but they'd burn in the atmosphere. Now, somebody please calculate whether the energy of the dust cloud converted into heat wouldn't cause us serious problems. I *guess* not, but I am not sure. It would be one hell of a meteor shower though, nice to watch.
Blow up some asteroids...?
I love how he speaks of Europe as if it was still the 18th century... Seriously, if you want to make an argument for space, use historical analogies sparingly.
Bigelow Aerospace had to do some layoffs, because the launch capabilities were slower than expected. That said, he's started re-hiring this year. Worth a resume!
http://www.spacenews.com/article/bigelow-ends-employee-furloughs-resumes-limited-hiring#.UK4uYIaaKSp
http://www.spacenews.com/article/bigelow-ends-employee-furloughs-resumes-limited-hiring#.UK4uYIaaKSp
hobbsyoyo
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It's a shame they haven't been able to team up with a launching company sooner. They have solid tech for orbital modules and have even demonstrated it on orbit. The sooner they get the ball rolling, the sooner humanity starts building true space infrastructure.
Crezth
i knew you were a real man of the left
It's embarrassing, really. When he got to "privatize everything" is when I really wanted to vomit, though.
PlutonianEmpire
King of the Plutonian Empire
http://news.yahoo.com/art-show-space-could-last-billions-years-181422545.html
http://news.yahoo.com/does-moon-levitating-lunar-dust-124621312.html
I think this article mentioned geostationary orbits being forever. I'm guessing he forgot about tidal acceleration slowing down Earth's rotation, but with current geostationary orbits being about 33,800 km, would satellites there be up there that long (5 Gy) anyway?
http://news.yahoo.com/does-moon-levitating-lunar-dust-124621312.html
Winner
Diverse in Unity
Elon Musk wants to send people to colonize Mars in "big reusable rockets"
-> I kind of don't get what he means from that article. You could have a big reusable rocket to launch a Mars lander directly from Earth, but the lander itself would *not* be reusable.
Anyway, $500,000? What would that give us - a millionaires' colony? Who's going to tidy up the habs if there are no illegal immigrants?
-> I kind of don't get what he means from that article. You could have a big reusable rocket to launch a Mars lander directly from Earth, but the lander itself would *not* be reusable.
Anyway, $500,000? What would that give us - a millionaires' colony? Who's going to tidy up the habs if there are no illegal immigrants?
hobbsyoyo
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Elon Musk wants to send people to colonize Mars in "big reusable rockets"
-> I kind of don't get what he means from that article. You could have a big reusable rocket to launch a Mars lander directly from Earth, but the lander itself would *not* be reusable.
Anyway, $500,000? What would that give us - a millionaires' colony? Who's going to tidy up the habs if there are no illegal immigrants?
Yeah he's been talking about this for at least a year or two, it's exciting stuff.
I wonder if they'll allow people to go there in exchange for labor either here on Earth or on Mars instead of cash payment. I wouldn't be surprised if they do once the program is on solid financial footing. Labor is going to be the most valuable commodity at a Martian colony for a long time after it's founding.
Winner
Diverse in Unity
Of course, that would be very highly qualified labour - engineers, lab geeks, robot operators, etc. I understand that some people might want to pay $500,000 for a chance at a new life on another planet, but what use would there be for, say, hedge fund managers? None whatsoever. Their migration to Mars would basically change them into unqualified labourers who would spend the rest of their days shovelling dirt or tending tomato plants in hydroponic greenhouses (some would say this would be an improvement, for us on the Earth at least
).
hobbsyoyo
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Sending only engineers, scientists and such would be a waste of their talents. There will actually be need of people to shovel dirt, so why only send engineers to do all of the tasks? I think their would be as much of a need for unqualified labor as their would be for experts.
Winner
Diverse in Unity
Because there will be little room for narrow specialization in the early phases. Every colonist will have to be able of repairing equipment, driving vehicles, managing life support systems, operating factories, checking computers, etc. etc. etc. Having people who can do nothing but shovel dirt would be a waste of oxygen, especially since the more mundane task will probably be done (tele)robotically.
(Of course, if a millionaire paid, say, twenty times as much as a qualified person, so that he could basically bring his own 'support team' with him (people who would do the useful work while he keeps wasting oxygen), it could work. For a time, until these people realized that nobody is going to kick them back to Earth if they break the contract
But other than that, I am sceptical about the prospects of sending ordinary Joes to Mars to play colonists. Mars is not the Old West.)
Crezth
i knew you were a real man of the left
(Of course, if a millionaire paid, say, twenty times as much as a qualified person, so that he could basically bring his own 'support team' with him (people who would do the useful work while he keeps wasting oxygen), it could work. For a time, until these people realized that nobody is going to kick them back to Earth if they break the contract
I couldn't agree more. We're not looking for "colonists" per se, we want to send people to build a self-sustainable arcology. Then we can start daydreaming about sending over Joe Schmo.
hobbsyoyo
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Hmm, but cannot a Joe Schmo be a Joe Schmo with enough specialized training to do basic tasks that need attention without being an expert at anything?
And I'm not even talking about the first wave of colonists who will indeed all be specialists. I'm talking about when they actually start sending people over with 500k tickets.
And I'm not even talking about the first wave of colonists who will indeed all be specialists. I'm talking about when they actually start sending people over with 500k tickets.
Winner
Diverse in Unity
Well, maybe. I just think that paying just for your way to Mars may not be enough if you don't have usable skills. I'd expect that with the degree of automation required to build a sustainable colony, the demand for unqualified labour will be low.
On the other hand, you know how it is - many jobs that require you to have a degree could in fact be performed by a trained chimp
Practical skills, mental resilience, and an aptitude for learning might be valued more by the colonists than fancy degrees from Earth universities. ---
Anyway, BBC reports on X-37B:
X-37B: Secrets of the US military spaceplane
hobbsyoyo
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Cool article, I didn't know they were looking to put people in the X-37.
Question:
What goes into 'man-rating' a rocket and why is it so hard to certify an existing, successfull system as 'man-rated' but not so hard to build an entirely new 'man-rated' system that is relatively untested compared to the workhorse systems?
Question:
What goes into 'man-rating' a rocket and why is it so hard to certify an existing, successfull system as 'man-rated' but not so hard to build an entirely new 'man-rated' system that is relatively untested compared to the workhorse systems?
Winner
Diverse in Unity
I think it's mostly about building-in additional redundancies and control sensors (beyond ensuring the rocket has the right acceleration profile that won't jellify the crew on launch, and perhaps also allow the launch abort system to be used in an emergency). I'd assume that a system well-optimized for unmanned launches may be difficult to "man-rate" because it encompasses messing with something that works well as it is.
Winner
Diverse in Unity
Yay! 
Screw Ariane-6. Competing with the likes of China and SpaceX in reusable rockets is a self-defeating proposition, especially since in Europe such projects are hampered by the need to give every key member country a slice of the production cake.
Let's take the risk, build Skylon, and show the rest of the world how space flight is done properly
Skylon spaceplane engine concept achieves key milestone
The UK company developing an engine for a new type of spaceplane says it has successfully demonstrated the power unit's enabling technology.
Reaction Engines Ltd (REL) of Culham, Oxfordshire, ran a series of tests on key elements of its Sabre propulsion system under the independent eye of the European Space Agency (Esa).
Esa's experts have confirmed that all the demonstration objectives were met.
REL claims the major technical obstacle to its ideas has now been removed.
"This is a big moment; it really is quite a big step forward in propulsion," said Alan Bond, the driving force behind the Sabre engine concept.
The company must now raise the £250m needed to complete the next phase of development.
This would essentially take the project to the final designs that could be handed to a manufacturer.
Although the British government has put significant sums into REL's technology in the past, the company's preference is to pursue city finance.
"The project to date has been more than 90% privately funded, and we intend to continue with that type of structure," explained Tim Hayter, the CEO of Reaction Engines Ltd.
"Yes, we would encourage government money but we're not reliant on it and we're certainly not depending on it.
"What is more important to us is government endorsement. That gives everyone the confidence that the UK is behind this project."
REL's idea is for an 84m-long vehicle called Skylon that would do the job of a big rocket but operate like an airliner, taking off and landing at a conventional runway.
The vehicle would burn a mixture of hydrogen and oxygen but in the low atmosphere the oxygen would be taken from the air, in the same way that a jet engine breathes air.
Only once it had achieved very high speeds would Skylon switch to full rocket mode, burning onboard fuel supplies.
Taking its oxygen from the air in the initial flight phase would mean Skylon could fly lighter from the outset with a higher thrust-to-weight ratio, enabling it to make a single leap to orbit, rather than using and dumping propellant stages on the ascent - as is the case with current expendable rockets.
If such a vehicle could be made to work, its reusability should transform the costs of accessing space.
But its success depends on the Sabre engine's ability to manage the very hot air entering its intakes at high speed.
These gases have to be cooled prior to being compressed and burnt with the onboard hydrogen.
REL's solution is a module containing arrays of extremely fine piping that can extract the heat and plunge the inrushing air to minus 140C in just 1/100th of a second.
Ordinarily, the moisture in the air would be expected to freeze out rapidly, covering the piping in a blanket of frost and dislocating their operation.
But the company's engineers have also devised a means to control the frosting, permitting the Sabre engine to run in jet mode for as long as is needed before making the transition to full rocket mode to take the Skylon spaceplane into orbit.
It is the innovative helium cooling loop with its pre-cooler heat-exchanger that REL has been validating on an experimental rig.
"We completed the programme by getting down to -150C, running for 10 minutes," said Mr Bond. "We've demonstrated that the pre-cooler is behaving absolutely as predicted."
The UK Space Agency asked Esa's propulsion division to audit the tests, and the Paris-based organisation has declared its satisfaction with the outcome of the experimental programme.
"One of the major obstacles to developing air-breathing engines for launch vehicles is the development of the lightweight high-performance heat exchangers," it said in a statement.
"With this now successfully demonstrated by REL, there are currently no technical reasons why the Sabre engine programme cannot move forward into the next stage of development."
The next phase is a three-and-a-half-year project. It would see a smaller version of Sabre being built on a test rig. The demonstrator would not have the exact same configuration as the eventual engine but it would allow REL to prove Sabre's performance across its air-breathing and rocket modes.
"Its parts will be spread out slightly; there's no need for us to package it as we would a real engine," said Mr Bond.
"Also, we will want the ease of access to exchange parts, so it will look a little bit like an anatomy exhibition."
The UK government is currently assessing what shape any involvement it should have in the next phase of Skylon/Sabre.
In addition, Esa is keen to do some study work with REL. Although it is currently working on new versions of its Ariane rocket - a classic expendable vehicle - the agency also wants keep an eye on future launcher technologies.
Screw Ariane-6. Competing with the likes of China and SpaceX in reusable rockets is a self-defeating proposition, especially since in Europe such projects are hampered by the need to give every key member country a slice of the production cake.
Let's take the risk, build Skylon, and show the rest of the world how space flight is done properly
Crezth
i knew you were a real man of the left
Winner said:
Yeah, this is a really good notion. A system optimized for unmanned launches is by definition not optimized for manned launches (assuming you change the mission profile, as you had better). So now you have new margins and everything and that requires new optimal parameters, and as everyone knows optimization is a tricky business. Insofar as man-rating goes, it's essentially the same dilemma.
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