Perhaps I was confused about your statement then, I thought the article was referring to local solar system sized objects, very few of which contain high power radio transmitters.
There are already hundreds of probes out in the solar system. Asteroids, comets, moons, and planets are all easily trackable (well, not so easy when you get to tiny little asteroids), and by studying their motion it is just a matter of computation to solve for all the important interactions in interplanetary space.
I don't mean to be picky, but radio astronomy and SETI have nothing to do with hearing. Despite what you may have seen in the movies, there are no headphones hooked up to radio telescopes, and if there were you would hear static no matter where the dishes were pointed. Also if you think SETI is some how going to help out by scanning the sky in radio and finding small objects you are mistaken. SETI only has time on Arecibo, (I believe, unless something has changed) and their reciever setup is not at all optimized for tracking objects. First off because Arecibo can't really move, and second because their entire goal is just to gather up all the static and look for patterns.
Homer: Used grease is worth money? [gasps] Then my arteries are clogged with yellow gold! I'm rich Apu! Rich, I... aaggh! [clenches heart, then sighs] Money in the bank.
Marge: Homer! That side of bacon was for my bridge game tonight! Homer: Marge, if you don't mind, I'm a little busy right now
achieving financial independence. Marge: With cans of grease? Homer: [sarcastically] No! Through savings and wise investment.
Of course with grease. Lisa: Come on, Bart, the bus is here. [grabs Bart] Homer: Where do you think you're going? Bart: It's the first day of school! Homer: Not for you it isn't. You're in the grease business now!
It is immensely easier to point out the problem than to fix it in this case. The amount of energy to push stuff into the sun or rendezvous with it and bring it back to earth would be insane. Considering the varying orbits of the junk, and the limits of current space propulsion, it would require hundreds of missions to bring it all back, and each mission would probably create some junk of its own.
Why would he burst into flames if his chute did not open? He's not planning on opening it until 1000m, well in the range of normal skydiving, so obviously the chute has no bearing on what happens above that. At this point he'll only be traveling at terminal velocity anyway, which ain't so fast (~160mph, rough estimate for a human body).
Actually, there is quite a bit left over after a supernova. Here is a VLA radio image of Cas A. If you see the area of high emission on the right edge of the expanding cloud, that is thought to be the compact object (probably neutron star) flying off from the force of the supernova.
Not only the Hubble, but just about every telescope out there (NSF funded ones especially) have the "Open Sky" policy. This says any person (note:not necessarily astronomer) who submits a proposal which is deemed the best use of the facilities gets the time they need. Also, this doesn't just apply (in the case of US scopes) to native observers, anyone in the world can apply and their project is judged solely on scientific merit.
As a possible combat to this a few people have been wondering if large radio telescopes (GBT, VLA, etc..) could put out enough power transmitting to disable communications satellites and clean up radio frequency interference. Of course this is entirely unrealistic since the electronics of the telescopes are designed for receiving not transmitting, but I think it would be funny if some radio astronomers blew out the front ends of all the Iridium satellites so they could study OH again.
Don't forget the OH line around 1620 MHz that got screwed by the Iridium satellites. Iridium played nice and stayed within their allocated band, but some harmonics of their frequencies landed right on top of the OH line. In my opinion it was sloppy engineering on their part. They have made it impossible to study OH masers and the like for the past few years.
Actually I thought the domes didn't so much protect the antennas from the elements as hide which direction the antenna was pointed. With satellite photography what it is now, it becomes very easy to see things as big as antennas and see exactly where they are looking. The domes probably did a little bit of both.
I wonder if this would involve "frame dragging" an occurence seen around black holes. As some massive black holes spin they tend to drag space with them, distorting it close to the event horizon. Assuming superman is approaching the speed of light, then his mass would be enormous and his speed would begin to drastically warp space around earth. While I can't work out how the extent of the warpage, there would definitely be some space-time changes on earth.
An x-ray maser? Maser = microwave amplification due to stimulated emission of radiation. Perhaps you've gotten something mixed up here, x-ray and microwave a distinctly different portions of the spectrum.
Thats a very good point. Quantum cryptography is essentially a form of One-time pad cryptography, which is an algorithm that uses a completely random assortment of characters as the key, and each key is used only once. This type of cryptography is said to be absolutely unbreakable, and in a realistic sense this is true. However, using brute force one can decode the possible message, but included with that you will get every other possible message that is of the same length as the encrypted message. This is what makes quantum cryptography so secure.
Some ideas called quantum cryptography, such as using polarized photons (quanta of light) rely on the quantum mechanical properties of the photons, but not necessarily quantum computing. A good overview of how this works is included in The Code Book, by Simon Singh, I suggest you give it a look. Without going into the detail here, I can tell you that if the quantum cryptography he describes ever works it would not only be absolutely secure (this can be mathematically proven) but by its nature you could tell if someone was eavesdropping on the line.
It was obviously someone with this attitude that attempted to rob some offices of physics professors at my school a few years back. Little did they know the professor they picked, while one of the best teachers I've ever had and one of the smartest people I know, also lifts daily and could kick my ass even though I'm about a foot taller and sixty pounds heavier. The professor returned as said thief was exiting the office, upon which he chased him into the parking lot of the building and tackled him. Then, because he was a nice guy, he let him go after he returned stolen items.
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All your science sounds good, I just thought I would throw in this link to picture of the Lagrange Points to make it easier to understand.
Perhaps I was confused about your statement then, I thought the article was referring to local solar system sized objects, very few of which contain high power radio transmitters.
There are already hundreds of probes out in the solar system. Asteroids, comets, moons, and planets are all easily trackable (well, not so easy when you get to tiny little asteroids), and by studying their motion it is just a matter of computation to solve for all the important interactions in interplanetary space.
I don't mean to be picky, but radio astronomy and SETI have nothing to do with hearing. Despite what you may have seen in the movies, there are no headphones hooked up to radio telescopes, and if there were you would hear static no matter where the dishes were pointed. Also if you think SETI is some how going to help out by scanning the sky in radio and finding small objects you are mistaken. SETI only has time on Arecibo, (I believe, unless something has changed) and their reciever setup is not at all optimized for tracking objects. First off because Arecibo can't really move, and second because their entire goal is just to gather up all the static and look for patterns.
Homer: Used grease is worth money? [gasps] Then my arteries are clogged with yellow gold! I'm rich Apu! Rich, I ... aaggh! [clenches heart, then sighs] Money in the bank.
Marge: Homer! That side of bacon was for my bridge game tonight!
Homer: Marge, if you don't mind, I'm a little busy right now
achieving financial independence.
Marge: With cans of grease?
Homer: [sarcastically] No! Through savings and wise investment.
Of course with grease.
Lisa: Come on, Bart, the bus is here. [grabs Bart]
Homer: Where do you think you're going?
Bart: It's the first day of school!
Homer: Not for you it isn't. You're in the grease business now!
It is immensely easier to point out the problem than to fix it in this case. The amount of energy to push stuff into the sun or rendezvous with it and bring it back to earth would be insane. Considering the varying orbits of the junk, and the limits of current space propulsion, it would require hundreds of missions to bring it all back, and each mission would probably create some junk of its own.
Why would he burst into flames if his chute did not open? He's not planning on opening it until 1000m, well in the range of normal skydiving, so obviously the chute has no bearing on what happens above that. At this point he'll only be traveling at terminal velocity anyway, which ain't so fast (~160mph, rough estimate for a human body).
Well I guess this just shows not only are Mac users smarter, but they read Slashdot.
Thats where I keep all my stuff.
Actually, there is quite a bit left over after a supernova. Here is a VLA radio image of Cas A. If you see the area of high emission on the right edge of the expanding cloud, that is thought to be the compact object (probably neutron star) flying off from the force of the supernova.
Not only the Hubble, but just about every telescope out there (NSF funded ones especially) have the "Open Sky" policy. This says any person (note:not necessarily astronomer) who submits a proposal which is deemed the best use of the facilities gets the time they need. Also, this doesn't just apply (in the case of US scopes) to native observers, anyone in the world can apply and their project is judged solely on scientific merit.
He must have realized that the current poll was meaningless, since it is obvious The Who is the greatest rock bacnd of all time.
Well if you really want to get picky, you would have to sue the producers of Alien for that line.
As a possible combat to this a few people have been wondering if large radio telescopes (GBT, VLA, etc..) could put out enough power transmitting to disable communications satellites and clean up radio frequency interference. Of course this is entirely unrealistic since the electronics of the telescopes are designed for receiving not transmitting, but I think it would be funny if some radio astronomers blew out the front ends of all the Iridium satellites so they could study OH again.
Don't forget the OH line around 1620 MHz that got screwed by the Iridium satellites. Iridium played nice and stayed within their allocated band, but some harmonics of their frequencies landed right on top of the OH line. In my opinion it was sloppy engineering on their part. They have made it impossible to study OH masers and the like for the past few years.
Actually I thought the domes didn't so much protect the antennas from the elements as hide which direction the antenna was pointed. With satellite photography what it is now, it becomes very easy to see things as big as antennas and see exactly where they are looking. The domes probably did a little bit of both.
I wonder if this would involve "frame dragging" an occurence seen around black holes. As some massive black holes spin they tend to drag space with them, distorting it close to the event horizon. Assuming superman is approaching the speed of light, then his mass would be enormous and his speed would begin to drastically warp space around earth. While I can't work out how the extent of the warpage, there would definitely be some space-time changes on earth.
I remember that exact problem, was the textbook by Paul A. Tipler?
An x-ray maser? Maser = microwave amplification due to stimulated emission of radiation. Perhaps you've gotten something mixed up here, x-ray and microwave a distinctly different portions of the spectrum.
Well...I think the device in Back to the Future was called Mr. Fusion. I don't think the process the article is referring to is atomic fusion.
Thats a very good point. Quantum cryptography is essentially a form of One-time pad cryptography, which is an algorithm that uses a completely random assortment of characters as the key, and each key is used only once. This type of cryptography is said to be absolutely unbreakable, and in a realistic sense this is true. However, using brute force one can decode the possible message, but included with that you will get every other possible message that is of the same length as the encrypted message. This is what makes quantum cryptography so secure.
Some ideas called quantum cryptography, such as using polarized photons (quanta of light) rely on the quantum mechanical properties of the photons, but not necessarily quantum computing. A good overview of how this works is included in The Code Book, by Simon Singh, I suggest you give it a look. Without going into the detail here, I can tell you that if the quantum cryptography he describes ever works it would not only be absolutely secure (this can be mathematically proven) but by its nature you could tell if someone was eavesdropping on the line.
It was obviously someone with this attitude that attempted to rob some offices of physics professors at my school a few years back. Little did they know the professor they picked, while one of the best teachers I've ever had and one of the smartest people I know, also lifts daily and could kick my ass even though I'm about a foot taller and sixty pounds heavier. The professor returned as said thief was exiting the office, upon which he chased him into the parking lot of the building and tackled him. Then, because he was a nice guy, he let him go after he returned stolen items.
Um, the sun moves exactly 15 degrees/hour (360 degrees/24 hours) since it is the movement of the sun that defines the length of the day.