But they can't re-use the fuel! So, declare the hydrogen filling of the ballon as the fuel and presto:)
The hydrogen filling of the balloon is fuel. Well, I can't particularly speak to the plan used by this particular team, but here's how I'd do it. I'd have my hydrogen balloon double as initial lift through the atmosphere and fuel tank. Once you get to an altitude at which the balloon really isn't helping very much, you start sucking the hydrogen into your engine, mix it with oxygen, and use it as a fuel source for your conventional thrusters to get the rest of the way out of the atmosphere.
Yes, I know some of you are going to say there isn't a lot of oxygen high up in the atmosphere; I was thinking more along the lines of bringing it in the traditional way that the space shuttle does, i.e. in liquid form in tanks.
You are confusing the fact that you may choose your acceleration rate with the idea that you don't have to attain a particular velocity to escape orbit.
Sorry, but you're still wrong. Let's try this simple exercise. Imagine a hypothetical craft that has finely-tuned engines capable of producing thrust at 1% above the gravitational pull at any given distance from Earth. Slowly... very slowly, the craft would lift off from the surface of the Earth, travel through the atmosphere, reach space, etc., because at every point in its travels it would be accelerating just above whatever g is at its particular distance from the Earth.
Shut the engines off every so often to bleed off speed and stay at a slow velocity, but never shut off the engines long enough to allow your velocity away from the Earth to become negative. You could travel at 1 m/s away from the Earth in this fashion to any arbitrary distance; it would just take awhile.
The definition of escape velocity is the velocity at which a projectile must be fired from an object's surface in order to come to rest at infinity. In this way, you'll see that the ballistic object would only be travelling at Mach 25 at the Earth's surface, and would slow down over time as it was attracted by the Earth's gravity - but it would never slow down enough to come to an actual stop (and by that point it'd be an infinite number of light-years away and out of the effect of Earth's gravity).
Escape velocity is a concept which is misunderstood by a great number of people. It applies only to ballistical orbits; those which have a large initial input of energy and then none thereafter. Obviously, everything we have ever done in spaceflight uses rockets and steady acceleration rather than a huge initial boost of energy which would liquify people and flatten the spacecraft. Escape velocity is a term that really doesn't apply to spacecraft with thrusters on them, because as long as you keep increasing your distance from the Earth, you'll escape.
I'd also like to point out that escape velocity is a function of the mass of the planet and the inverse-square of the distance to that planet. Yes, to eventually escape from a planet's gravity well you would have to exceed escape velocity - but that escape velocity is not anything so concrete as "Mach 25". The farther away from the planet, the lower the escape velocity is. With my aforementioned example of a craft that is always moving 1 m/s away from the Earth, keep on thrusting until you reach a distance from Earth at which point the escape velocity is 1 m/s, and boom, you can turn off your engines and you'll still be free from the Earth forever.
By the time you factor in extended life support and the heat shielding needed to survive reentry, orbital flight becomes a much thornier problem that almost certainly won't be solved in a decade.
You're right, orbital flight is a thorny problem... one that was solved four decades ago. Remember the Apollo missions?
Your post is kind of misleading. May I remind you that escape velocity is defined as the initial velocity necessary to leave the Earth's gravity well provided that there is no additional acceleration. As long as your acceleration away from Earth is greater than than the Earth's gravitational acceleration at your distance from it, you will eventually escape Earth's gravity well, and at a speed of much less than Mach 25 to boot. Think of a balloon: they certainly never travel very quickly, but they get very far towards escaping on very small velocity.
A spaceship is not launched like a cannon, but rather, it has engines on it that provide thrust. In this way it is possible to escape Earth's gravity with continual acceleration and never actually experiencing speeds of Mach 25. You are right, to get into a low-Earth orbit one would need to be travelling at Mach 25, but that is simply a result of the Newtonian mechanics of an orbit plotted at that arbitrary altitude. Any number of different orbits - such as a parabolic orbit arcing away from the Earth - could have any number of different (higher or lower) necessary velocities.
And besides, once you are in space, without having to worry about air resistance, it's trivially easy to build up that extra velocity. Your post makes it sound like getting to Mach 3 is trivial and they need to put in eight times the work to reach LEO. This is simply not true. Getting to 100km through most of the atmosphere has already accomplished most of the work. The rest is easy. It's not as simple as looking at the difference between the numbers 3 and 25 and saying, "Oh, they have eight times more speed they need to get!"
This is a great day for man. I firmly believe that our future lies in some day getting off this Earth and spreading throughout space. As such, the accomplishment we have witnessed today was great. This heralds a new era of spaceflight, not one in which governments spend billions, but one in which small companies pay millions, to get into orbit. At this rate, in ten years, commercial space flight might be a reality - and space exploitation (and as a side-effect, human colonization of space) would occur. See any number of novels by Stephen Baxter for more details.
I experienced this with my Matshita UJ-815 SuperDrive on my PowerBook G4. It was acting like crap, turning 3/4ths of DVDs I tried to burn into coasters. So I looked online for updated firmware and found some unofficial firmware that doubled the DVD and CD burn rates as well as removing region code lock-outs. Since I installed that upgraded firmware, I've been reliably burning DVDs at 2X and I haven't produced a single coaster. Kind of makes you wonder how the original firmware the drive ships with could possibly be any more crippled.
but when you're 60 and you can say "I've found the Amulet of Yendor" it will all be worth it.
First you have to make sure it's the REAL Amulet of Yendor and not a "cheap plastic imitation", and even then it only counts if you escape from the dungeon with it and Ascend to Demigodhood.
The nano in nanobacteria doesn't mean that it's the one-billionth the size of a bacteria, it just means that it's like a bacteria, only on the scale of nanometers.
Re:We don't use oil for Electricity
on
Out of Gas
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· Score: 1
The United States has about 800 years of coal left according to predicted usage rates (accounting for increased consumption). The physical processes that produce coal are a LOT easier than those that produce oil, so there is hundreds of times as much coal in the Earth as oil.
The computer I'm currently on is a 15" PowerBook I got about nine months ago from a friend who bought it and then sold it secondhand to me a week after he got it at a hefty discount (he didn't like it or something). So I believe the story.
While they do measure stuff like access times in ms, they don't mention recovery times (chkfs) that are mentioned in ms for reiserfs and mins for ext2. And they don't mention reinstallation times (measured in hours) which occurs for ext2 a lot more than the journalling filesystems:-)
Because black is darker and absorbs more light there are less reflections of the 650nm blue laser which writes the data to the disc. therefor the beam is more exact and the data's more secure.
I hate to break it to you, but 650nm is RED, not blue. Blue is 450nm. And anyways, current DVD technology doesn't use blue lasers anyway... they use red lasers. Blue lasers are coming with that "Blu-Ray" technology.
You know what, we made fun of California because we thought they didn't take their Democracy seriously by electing an action movie star, but apparently they take it a lot more seriously than we realize. I have to admit, Arnold is doing a lot better than I thought he would; hell, if I lived in California, I'd vote for him for re-election (even though I'm a Democrat). And the way they're treating this Diebold issue is very much to be applauded. I live in Maryland and we recently had big problems with electronic polling machines, but our politicians didn't really do anything about it. Bravo to California for standing up for its citizens rights to vote.
The gyroscope that failed isn't used to measure orientation in space, but rather, to CONTROL orientation in space. You ever played around with a gyroscope, or a bicycle wheel on an axis, or anything? When you spin it up it resists movement along certain axes in relation to its own axis of rotation. It "pushes back". The gyros being used on the ISS are big massive suckers that are used to control the ISS's position in space, not to simply measure it. Fiber optic gyros would thus not suffice for this purpose.
The conductor is largely there to take credit for the production; for the most part, the symphony is self-conducting. These are all skilled musicians we're talking about. They know how to carry a tune, they know the songs by heart, and they have excellent timing. A conductor is there to add a certain flourish and an individual face to the performance.
580 tons? How in the hell are you supposed to ship that thing?! There isn't a truck big enough, nor a road strong enough to take that load. It wouldn't fit on a rail car. I just don't see how someone can put up an auction when they know there's no way possible the bidder can collect the item they've won.
I know I'm going against the typical slashdot privacy concerns thing, but I think this is a good thing. As a person who pays all of his taxes, I think everything possible should be done to catch the tax evaders. There are many battles you privacy advocates can choose to fight - this shouldn't be one of them though.
Naw you've got it all wrong. People can be Decidedly Dead, Partially Petrified, or Predominantly Pregnant - all three of which occurred due to the NYC 911 outage.
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But they can't re-use the fuel! So, declare the hydrogen filling of the ballon as the fuel and presto :)
The hydrogen filling of the balloon is fuel. Well, I can't particularly speak to the plan used by this particular team, but here's how I'd do it. I'd have my hydrogen balloon double as initial lift through the atmosphere and fuel tank. Once you get to an altitude at which the balloon really isn't helping very much, you start sucking the hydrogen into your engine, mix it with oxygen, and use it as a fuel source for your conventional thrusters to get the rest of the way out of the atmosphere.
Yes, I know some of you are going to say there isn't a lot of oxygen high up in the atmosphere; I was thinking more along the lines of bringing it in the traditional way that the space shuttle does, i.e. in liquid form in tanks.
You are confusing the fact that you may choose your acceleration rate with the idea that you don't have to attain a particular velocity to escape orbit.
... very slowly, the craft would lift off from the surface of the Earth, travel through the atmosphere, reach space, etc., because at every point in its travels it would be accelerating just above whatever g is at its particular distance from the Earth.
Sorry, but you're still wrong. Let's try this simple exercise. Imagine a hypothetical craft that has finely-tuned engines capable of producing thrust at 1% above the gravitational pull at any given distance from Earth. Slowly
Shut the engines off every so often to bleed off speed and stay at a slow velocity, but never shut off the engines long enough to allow your velocity away from the Earth to become negative. You could travel at 1 m/s away from the Earth in this fashion to any arbitrary distance; it would just take awhile.
The definition of escape velocity is the velocity at which a projectile must be fired from an object's surface in order to come to rest at infinity. In this way, you'll see that the ballistic object would only be travelling at Mach 25 at the Earth's surface, and would slow down over time as it was attracted by the Earth's gravity - but it would never slow down enough to come to an actual stop (and by that point it'd be an infinite number of light-years away and out of the effect of Earth's gravity).
Escape velocity is a concept which is misunderstood by a great number of people. It applies only to ballistical orbits; those which have a large initial input of energy and then none thereafter. Obviously, everything we have ever done in spaceflight uses rockets and steady acceleration rather than a huge initial boost of energy which would liquify people and flatten the spacecraft. Escape velocity is a term that really doesn't apply to spacecraft with thrusters on them, because as long as you keep increasing your distance from the Earth, you'll escape.
I'd also like to point out that escape velocity is a function of the mass of the planet and the inverse-square of the distance to that planet. Yes, to eventually escape from a planet's gravity well you would have to exceed escape velocity - but that escape velocity is not anything so concrete as "Mach 25". The farther away from the planet, the lower the escape velocity is. With my aforementioned example of a craft that is always moving 1 m/s away from the Earth, keep on thrusting until you reach a distance from Earth at which point the escape velocity is 1 m/s, and boom, you can turn off your engines and you'll still be free from the Earth forever.
By the time you factor in extended life support and the heat shielding needed to survive reentry, orbital flight becomes a much thornier problem that almost certainly won't be solved in a decade.
... one that was solved four decades ago. Remember the Apollo missions?
You're right, orbital flight is a thorny problem
Your post is kind of misleading. May I remind you that escape velocity is defined as the initial velocity necessary to leave the Earth's gravity well provided that there is no additional acceleration. As long as your acceleration away from Earth is greater than than the Earth's gravitational acceleration at your distance from it, you will eventually escape Earth's gravity well, and at a speed of much less than Mach 25 to boot. Think of a balloon: they certainly never travel very quickly, but they get very far towards escaping on very small velocity.
A spaceship is not launched like a cannon, but rather, it has engines on it that provide thrust. In this way it is possible to escape Earth's gravity with continual acceleration and never actually experiencing speeds of Mach 25. You are right, to get into a low-Earth orbit one would need to be travelling at Mach 25, but that is simply a result of the Newtonian mechanics of an orbit plotted at that arbitrary altitude. Any number of different orbits - such as a parabolic orbit arcing away from the Earth - could have any number of different (higher or lower) necessary velocities.
And besides, once you are in space, without having to worry about air resistance, it's trivially easy to build up that extra velocity. Your post makes it sound like getting to Mach 3 is trivial and they need to put in eight times the work to reach LEO. This is simply not true. Getting to 100km through most of the atmosphere has already accomplished most of the work. The rest is easy. It's not as simple as looking at the difference between the numbers 3 and 25 and saying, "Oh, they have eight times more speed they need to get!"
This is a great day for man. I firmly believe that our future lies in some day getting off this Earth and spreading throughout space. As such, the accomplishment we have witnessed today was great. This heralds a new era of spaceflight, not one in which governments spend billions, but one in which small companies pay millions, to get into orbit. At this rate, in ten years, commercial space flight might be a reality - and space exploitation (and as a side-effect, human colonization of space) would occur. See any number of novels by Stephen Baxter for more details.
you can think of it as the food buffer of the octospiders - when it's gone, we have but seconds to live.
Wow, that's the first time I've ever heard an obscure reference made to Arthur C. Clarke's Rendezvous With Rama series. Bravo, maxbang. Bravo.
I experienced this with my Matshita UJ-815 SuperDrive on my PowerBook G4. It was acting like crap, turning 3/4ths of DVDs I tried to burn into coasters. So I looked online for updated firmware and found some unofficial firmware that doubled the DVD and CD burn rates as well as removing region code lock-outs. Since I installed that upgraded firmware, I've been reliably burning DVDs at 2X and I haven't produced a single coaster. Kind of makes you wonder how the original firmware the drive ships with could possibly be any more crippled.
but when you're 60 and you can say "I've found the Amulet of Yendor" it will all be worth it.
First you have to make sure it's the REAL Amulet of Yendor and not a "cheap plastic imitation", and even then it only counts if you escape from the dungeon with it and Ascend to Demigodhood.
Can I get your AIM screen name then?
The nano in nanobacteria doesn't mean that it's the one-billionth the size of a bacteria, it just means that it's like a bacteria, only on the scale of nanometers.
The United States has about 800 years of coal left according to predicted usage rates (accounting for increased consumption). The physical processes that produce coal are a LOT easier than those that produce oil, so there is hundreds of times as much coal in the Earth as oil.
The computer I'm currently on is a 15" PowerBook I got about nine months ago from a friend who bought it and then sold it secondhand to me a week after he got it at a hefty discount (he didn't like it or something). So I believe the story.
While they do measure stuff like access times in ms, they don't mention recovery times (chkfs) that are mentioned in ms for reiserfs and mins for ext2. And they don't mention reinstallation times (measured in hours) which occurs for ext2 a lot more than the journalling filesystems :-)
Because black is darker and absorbs more light there are less reflections of the 650nm blue laser which writes the data to the disc. therefor the beam is more exact and the data's more secure.
... they use red lasers. Blue lasers are coming with that "Blu-Ray" technology.
I hate to break it to you, but 650nm is RED, not blue. Blue is 450nm. And anyways, current DVD technology doesn't use blue lasers anyway
You know what, we made fun of California because we thought they didn't take their Democracy seriously by electing an action movie star, but apparently they take it a lot more seriously than we realize. I have to admit, Arnold is doing a lot better than I thought he would; hell, if I lived in California, I'd vote for him for re-election (even though I'm a Democrat). And the way they're treating this Diebold issue is very much to be applauded. I live in Maryland and we recently had big problems with electronic polling machines, but our politicians didn't really do anything about it. Bravo to California for standing up for its citizens rights to vote.
The gyroscope that failed isn't used to measure orientation in space, but rather, to CONTROL orientation in space. You ever played around with a gyroscope, or a bicycle wheel on an axis, or anything? When you spin it up it resists movement along certain axes in relation to its own axis of rotation. It "pushes back". The gyros being used on the ISS are big massive suckers that are used to control the ISS's position in space, not to simply measure it. Fiber optic gyros would thus not suffice for this purpose.
The conductor is largely there to take credit for the production; for the most part, the symphony is self-conducting. These are all skilled musicians we're talking about. They know how to carry a tune, they know the songs by heart, and they have excellent timing. A conductor is there to add a certain flourish and an individual face to the performance.
580 tons? How in the hell are you supposed to ship that thing?! There isn't a truck big enough, nor a road strong enough to take that load. It wouldn't fit on a rail car. I just don't see how someone can put up an auction when they know there's no way possible the bidder can collect the item they've won.
I know I'm going against the typical slashdot privacy concerns thing, but I think this is a good thing. As a person who pays all of his taxes, I think everything possible should be done to catch the tax evaders. There are many battles you privacy advocates can choose to fight - this shouldn't be one of them though.
If that camera is always on, it's gonna be catching a lot of junks when I got into a locker room.
dictionary.com pulled a REAL April Fool's joke. That took guillible out of their online dictionary for the day!
$699 for a PDA? The price of a bargain laptop? APRIL FOOL'S!!!
128 Gigaflops? April's Fools!
(Hey, it's started already, just look at that pigeon story).
Naw you've got it all wrong. People can be Decidedly Dead, Partially Petrified, or Predominantly Pregnant - all three of which occurred due to the NYC 911 outage.
In 10 years doesn't fall within my definition of soon. Whose definition of soon were they using anyway, a geologist's?