You're saying that SABRE works well in theory, then you say that scramjets, despite working well in theory, are much more difficult in practice. This doesn't make SABRE a better design. It just means that SABRE's engineering difficulties have not yet been demonstrated by actually flying.
You'd of course need enough antimatter to balance the weight of the car. Let's call it 1500 kg of antimatter per car. Multiply by 2 for two cars and by 2 again for the mass of normal matter gives 6000 kg total being annihilated. That has an energy equivalent of 5*10^20 joules, which per wikipedia was the total world energy consumption in 2010. This is also equivalent to about 10^5 megatons of TNT or 2000 Tsar Bombas.
Maybe any number of crazy things happen beyond our cosmological horizon. We'll never see them so it's not relevant. The observable universe is matter-dominated.
That's an interesting point. It's worth noting, though, that most of those astronauts wrote memoirs decades after their flights. Maybe in another ten or twenty years we'll see more writings from current astronauts and space tourists.
Assuming the cost is on the same scale, would you pay a few hundred grand for a few weeks in orbit?
If the cost were that low, and I had the money somehow, I'd love to spend it on a few weeks in orbit. However, recognizing how much harder it is to get into orbit than to just go straight up, I have strong doubts that costs won't be a factor of 10 or 100 higher.
Also, since it's already taken more than twice as long as originally projected for this thing to be ready, I wouldn't expect anything orbital before 2020 or so.
You can still find them if you dig hard enough. "Unfortunately" the music doesn't work in my browser but you can always click the link at the bottom for a sample.
In the real world, that's a whole lot harder than it sounds. It's easy enough to get to an arbitrary LEO satellite, assuming you know its orbit well enough, but any dismantling and reusing would be extraordinarily difficult. This counts doubly for decommissioned satellites or debris which could be tumbling in some arbitrary fashion with no way to control. Plus, manufacturing in space is really really hard, as we've learned over 30 years of the Space Shuttle and 15 of the ISS. You probably need to launch lots of equipment (plus maybe a human or two, though no existing manned vehicle is up to the task) to make it work, and now you're doing much more work and spending much more money than you would just building something from scratch. And then of course here's the kicker: you've done all this work, and now (assuming you didn't leave anything new behind) you've removed one single piece of space junk. With the mass you've already needed to bring up to do your repair/retrofit, it's highly unlikely you'll have fuel to get to another object in even a very close orbit, and so you have to head home and launch another mission. And another. For every single piece of junk out there. It'd be absolutely impossible to make this work on a large enough scale to do anything about the debris problem.
Slashdot Mirror
Remind me again why Bennett Haselton gets to use the Slashdot front page as his personal blog?
Wow, I hadn't realized igoogle was still up. They announced it's closure much earlier than reader and yet it's going to live three months longer.
I've been looking at commafeed and old reader and liking them both. Neither has a mobile app though which is one thing I'll miss from google reader.
Who cares? Nobody's going to read it.
Well I'm glad Slashdot headlines are at least becoming honest about the substance-free stories we've been seeing lately.
When I stick a dvd in my computer and hit "play with vlc" I never seem to have this problem
You're saying that SABRE works well in theory, then you say that scramjets, despite working well in theory, are much more difficult in practice. This doesn't make SABRE a better design. It just means that SABRE's engineering difficulties have not yet been demonstrated by actually flying.
Or an attack on the nice big crowd waiting in the tsa checkpoint line.
That's datawinders, actually.
Newton didn't predict elliptical orbits. He explained them after Kepler observed and computed them.
You'd of course need enough antimatter to balance the weight of the car. Let's call it 1500 kg of antimatter per car. Multiply by 2 for two cars and by 2 again for the mass of normal matter gives 6000 kg total being annihilated. That has an energy equivalent of 5*10^20 joules, which per wikipedia was the total world energy consumption in 2010. This is also equivalent to about 10^5 megatons of TNT or 2000 Tsar Bombas.
Maybe any number of crazy things happen beyond our cosmological horizon. We'll never see them so it's not relevant. The observable universe is matter-dominated.
Guy who was late to the party says the party was boring anyway.
That's an interesting point. It's worth noting, though, that most of those astronauts wrote memoirs decades after their flights. Maybe in another ten or twenty years we'll see more writings from current astronauts and space tourists.
Assuming the cost is on the same scale, would you pay a few hundred grand for a few weeks in orbit?
If the cost were that low, and I had the money somehow, I'd love to spend it on a few weeks in orbit. However, recognizing how much harder it is to get into orbit than to just go straight up, I have strong doubts that costs won't be a factor of 10 or 100 higher. Also, since it's already taken more than twice as long as originally projected for this thing to be ready, I wouldn't expect anything orbital before 2020 or so.
2011? I remember when they were saying 2007.
You can still find them if you dig hard enough. "Unfortunately" the music doesn't work in my browser but you can always click the link at the bottom for a sample.
This is the World Wide Web. Gore's "invention" was the internet.
Most tripods of reasonable quality that I'm aware of do both.
Autocorrect can be easily disabilities
I agree
There's plenty of interesting moons in the Solar System, but not a single one I'd call "wonderfully earth-like".
Weather and research satellites are going to be having trouble from budget shortfalls even without considering orbital debris problems.
In the real world, that's a whole lot harder than it sounds. It's easy enough to get to an arbitrary LEO satellite, assuming you know its orbit well enough, but any dismantling and reusing would be extraordinarily difficult. This counts doubly for decommissioned satellites or debris which could be tumbling in some arbitrary fashion with no way to control. Plus, manufacturing in space is really really hard, as we've learned over 30 years of the Space Shuttle and 15 of the ISS. You probably need to launch lots of equipment (plus maybe a human or two, though no existing manned vehicle is up to the task) to make it work, and now you're doing much more work and spending much more money than you would just building something from scratch. And then of course here's the kicker: you've done all this work, and now (assuming you didn't leave anything new behind) you've removed one single piece of space junk. With the mass you've already needed to bring up to do your repair/retrofit, it's highly unlikely you'll have fuel to get to another object in even a very close orbit, and so you have to head home and launch another mission. And another. For every single piece of junk out there. It'd be absolutely impossible to make this work on a large enough scale to do anything about the debris problem.
This will not exacerbate the problem in any way
"Let's make a big mess, to motivate ourselves to fix that other big mess."