Yes - non-commercial radio is alive and well in the U.S. - for now. I DJ at a local station which is sort of a half-college/half-local community station. We play jazz, classical, folk, world, rock, and RPM, and broadcast the BBC news. As a DJ, I'm required to play or read 2 public service announcements and 2 promos for other shows per hour. In addition, if a local business sponsors my show, I have to read something about them. Combine that with me reading my playlist to the listeners, and you have about 5-7 minutes of talking each hour. The rest is just music. And it's good music that you won't hear on commercial stations. I play mostly downtempo electronic music - stuff which I love and want to share with other people, and which you will definitely not hear on commercial radio.
Community radio is supported mostly by the community (duh). It depends on local businesses sponsoring programs which it airs, and local listeners pledging money during fund drives. Without that money, we can't exist. At my station, there are 3 full-time, salaried employees, and the rest of the ~100 people who work there are volunteers. It's a fairly noble effort (not as noble as feeding the hungry or anything, but noble still).
Anyway, there are lots of community radio stations. There's a listing at the National Federation of Community Broadcasters website. Look for one in your area and check it out. If you appreciate what you hear, please consider supporting them. Even with most people volunteering, running a radio station is expensive, and if these stations go away, we're all seriously screwed into listening to to the (largely) crap that the commercial stations feed us.
I had the pleasure of seeing 'Dial M for Murder' in 3D at a film festival a couple years ago. It's a great movie, and 3D is cool, but I don't think 3D was really necessary in this case. Clearly an example of using a new (at the time), trendy technology as a gimmick. No disrespect to Hitchcock intended. Was this technique overused when it first became available?
Oops... It was actually the second French trans-Atlantic cable that went to Cape Cod, and was laid a few years later. I guess I need to go back to the musem to get re-edumacated...
Along the lines of your Stephenson reference...
I visited the French Cable Station Museum in Orleans, Cape Cod. It was really very interesting. This is a small museum in the original building where the first French trans-Atlantic submarine communications cable (laid in 1869) connected to the U.S. They have all of the orginal equipment used to send and receive communications, including one of the earliest (I presume) A to D converters which read to and from paper tape.
There weren't many visitors in the museum, and the elderly gentlemen who volunteered there were extremely friendly and more than willing to give an extensive tour of the place and all the equipment. I'd recommend it if you find yourself in that area. As they might say up there, "It's wicked pissah!"
A quick search did not reveal a website for the museum, but there is a bit about it here.
Actually, another problem with P2P between individual astronomers that I forgot to mention: Data takes up a lot of space. I've done work using mosaic cameras (where multiple CCDs are butted up together to make a large array) where single images are ~250MB. A single night's observing can produce many GB of data. Most people don't have enough disk space to store all of their data indefinitely. Most of the time, you do your work with it, and then write it to DLT or Exabyte and delete it from the hard drive to make space for the next data that you collect. In this sense, P2P wouldn't work well because most of the data which people have would not be easily accessible from remote locations.
That's a pretty interesting idea, but I don't think it's applicable to the Virtual Observatory. What is being discussed here is creating a central engine which can seamlessly access multiple large databases which are served out of different locations. These are databases which are frequently all-sky surveys conducted by one group and stored in one central location - not necessarily in small sections on multiple persons' hard drives.
The P2P idea is interesting in that it could apply to individually collected small data sets. Here's how observational astronomy has traditionally worked:
Astronomer writes a proposal to do some research using a specific telescope(s)
Proposal gets accepted after peer review
Astronomer travels to observatory to spend many of his own nights collecting data
Astronomer takes the time to reduce and analyze his own data
Astronomer writes a paper(s) saying, "Hey - look what I did!"
(Sometimes) astronomer writes a proposal for further funding based on the merits of this work
This procedure is inefficient in that you sometimes get multiple people who are not working together, doing the same project on different telescopes. If I collect a bunch of data in one part of the sky, try to use it but don't actually get around to finishing and publishing a paper, and then archive it locally, nobody in the world knows that the data exists.
So now if someone else wants to do the same project, they go to the telescope and recollect the same data. In other words, there's no central log of who's done what when it comes to individual observing.
P2P could be useful to remedy this. The problem is that astronomers tend to be very proprietary about their data. Sometimes research and publishing can be very competitive, and you don't want to give the competition an edge when it could mean that they publish a paper on a particular topic before you and reap the rewards, or get funding when you don't. So I think that most astronomers would share their data openly in a P2P network only after they were completely finished using it, and some would never do so.
The difference with the data sets being accessed by the proposed Virtual Observatory is that the people who create those sets typically get their funding with a stipulation that the data be publically accessible some time after the work is finished. They're not allowed to keep it proprietary even if they'd prefer to do so for competition reasons.
Perhaps someone who got 1600 on their SATs should take charge of the online movie distribution business. It's far too complicated for any of the rest of us mouth-breathers.
I got a perfect score on my breathalizer test, but I don't go around bragging about the 1.0
The other day I was using my overclocked, water-cooled Linux PS2 to
write some assembly code to automatically
record ST:TNG while I'm out seeing TTT on November
18th. I knew it was going to take a while, so first, I used vi to write
a Perl script to have my NeXT workstation brew a fresh pot of java every
30 minutes using the Mr. Coffee clone that I built out of legos.
Everything was going fine for a while, but then I started thinking about M$,
the RIAA, the MPAA, the DMCA, and all those goddamned emacs users, and I
found my blood boiling. So I tried playing a little Q3 to get my agressions
out. But despite being l337, I was getting fragged badly because
the ping on my 802.11b network was too high. So I gave up and settled down
in front of my plasma TV to watch Babylon 5.
Yep - somethin's screwy in the article. Not surprising, though - the press frequently garbles science/technology stories to the point of being flat-out wrong on small, but significant points.
As was pointed out above, beta particles (electrons) can be easily stopped with thin sheets of metal which introduce large electrical interaction cross-sections. Alpha particles are too large to penetrate the skin to a significant depth and are only dangerous if ingested.
When I was a physics TA in college, we worked with radioactive pellets for some labs, and I was told that I actually had to tell the students that they 'should not eat the radiation sources'. I'm sure several of them would have tried if I hadn't warned them...
I don't see them being so quick to remove a similar hurdle for nuclear fuel.
Why not? What are you going to do with a radioactive lump of stuff? I suppose you could try to choke someone with it or shoot people with beta particles...
This isn't the same sort of material that gets used in nuclear weapons; it's just isotopic material which decays with a characteristic timescale so that a steady stream of particles shoot away from it. You can use the momentum imparted by these particles to power a small generator - sort of like water turning a turbine in a dam or something (not exactly, but you get the picture...).
That may be true for you, but I don't think it's true for most people. I buy things online for 2 primary reasons: (1) I can't find some stuff I want in the moderately-sized city in which I live, and (2) I'm busy (and a little lazy), so I shop online to save time over physically going to the store. I've even sunk so low as ordering stamps from the USPS to save the time I would spend going to the post office.
Adding sales tax would suck, but it wouldn't prevent me from shopping online.
From the description in the article and my knowledge of celestial mechanics, it sounds like this object is effectively bouncing back and forth between Earth's Lagrange points L4 and L5. These are points where the combination of gravitational pull from the Sun and the Earth would have the effect of allowing the object to maintain a stable orbit around the sun in what would otherwise be an unstable position.
Basically, at a given orbital energy, or velocity, and object can orbit at a certain distance from the central mass (the Sun in this case). If it speeds up, it has to move to a smaller orbital radius. If it slows down, it moves to a larger orbital radius. In this case, it sounds like the following may be happening:
(1) The asteroid is moving faster than the Earth, and so travels in a slightly lower orbit. When it gets to one Lagrange point, it will slightly overrun it, and the Earth's pull will send it to a higher orbit, stealing some of its kinetic energy. It then slows down and the Earth speeds away from it.
(2) The now slower-moving, higher-orbiting asteroid moves backward with respect to the Earth, until the Earth catches up to it until it overruns the other Lagrange point. When that happens, the Earth pulls it into a lower, more energetic orbit, and it proceeds to speed away from the Earth.
(3) go back to #1 and repeat.
During the brief time that the Earth's influence on the asteroid is greater than that of the Sun, the asteroid technically becomes a satellite of the Earth.
I could be wrong about all this, but at first read, this was how I interpreted things...
It's true that dust in the Milky Way's disk makes it difficult to see to great distances in that part of the sky, but you're talking about visual light. If you look at the sky at radio or IR wavelengths, for example, the dust is transparent and we can get a pretty good idea of the structure of the Milky Way. The difficulty is in translating these observations into a 3-D model of the Galaxy. The problem is that we can see stars and measure their positions in the sky, but it's hard to determine their distance accurately; of course, you need the distance to get a full 3-D map of these stars in the Galaxy. Anyway... the point is that we can in fact observe most of our own Galaxy from our unique perspective embedded in it, and we are making progress in mapping it fully, but there's still a lot of work to do.
For something like Powers of Ten, as others have said, it's easiest to just use a photo of another spiral galaxy which we presume looks similar to what we would see if we could photograph the Milky Way from outside of it. We can do a pretty good job of finding an external "twin" galaxy, because there are a ton of them to choose from, and we have a good idea of what our own galaxy is shaped like.
"Powers of Ten" is definitely a classic science video, and the zoom effect is pretty good considering that it was made in 1968. Some of you may have seen "Cosmic Voyage", which is an IMAX film that came out a few years ago, narrated by Morgan Freeman. It's a bit more expansive in subject material than Powers of Ten, but it also contains a similar continuous zoom from the Earth out to a distance which shows the large-scale structure of the universe, and then back down to microsopic scales. This one is computer-generated. It's very cool. The video is available for sale if anyone's interested, and I think some IMAX theaters (especially ones in science museums) still show it.
I have to agree. During the time I lived in California, it seemed (probably just due to faulty memory) like most of the earthquakes occurred at night, and I would generally not even wake up unless they registered maybe 5.5 or so. I never heard about real earthquake damage until the Loma Prieta quake of 1989. I lived in Los Gatos at the time - just a few miles from the epicenter. That one scared the bejesus out of people. Damage, loss of life... it was no fun at all. Anyway, a 5.2 shouldn't matter in California; it might matter someplace like Mexico City. To a Californian, a 5.2 is just a cheap substitute for a kid's amusement park ride - a mild, momentary thrill. Your biggest concern is not spilling your cappucino. Still - I'm glad to hear that people (at least a few/.ers) are okay.
'Legend' is probably right. If I recall correctly, that quake occurred somewhere around 5:00pm, so school would have been out. Still, it makes a good story, so I won't tell anyone if you won't...
Slashdot Mirror
Community radio is supported mostly by the community (duh). It depends on local businesses sponsoring programs which it airs, and local listeners pledging money during fund drives. Without that money, we can't exist. At my station, there are 3 full-time, salaried employees, and the rest of the ~100 people who work there are volunteers. It's a fairly noble effort (not as noble as feeding the hungry or anything, but noble still).
Anyway, there are lots of community radio stations. There's a listing at the National Federation of Community Broadcasters website. Look for one in your area and check it out. If you appreciate what you hear, please consider supporting them. Even with most people volunteering, running a radio station is expensive, and if these stations go away, we're all seriously screwed into listening to to the (largely) crap that the commercial stations feed us.
I think Tron would be cool in 3D.
Oops... It was actually the second French trans-Atlantic cable that went to Cape Cod, and was laid a few years later. I guess I need to go back to the musem to get re-edumacated...
I visited the French Cable Station Museum in Orleans, Cape Cod. It was really very interesting. This is a small museum in the original building where the first French trans-Atlantic submarine communications cable (laid in 1869) connected to the U.S. They have all of the orginal equipment used to send and receive communications, including one of the earliest (I presume) A to D converters which read to and from paper tape.
There weren't many visitors in the museum, and the elderly gentlemen who volunteered there were extremely friendly and more than willing to give an extensive tour of the place and all the equipment. I'd recommend it if you find yourself in that area. As they might say up there, "It's wicked pissah!"
A quick search did not reveal a website for the museum, but there is a bit about it here.
Actually, another problem with P2P between individual astronomers that I forgot to mention: Data takes up a lot of space. I've done work using mosaic cameras (where multiple CCDs are butted up together to make a large array) where single images are ~250MB. A single night's observing can produce many GB of data. Most people don't have enough disk space to store all of their data indefinitely. Most of the time, you do your work with it, and then write it to DLT or Exabyte and delete it from the hard drive to make space for the next data that you collect. In this sense, P2P wouldn't work well because most of the data which people have would not be easily accessible from remote locations.
The P2P idea is interesting in that it could apply to individually collected small data sets. Here's how observational astronomy has traditionally worked:
Astronomer writes a proposal to do some research using a specific telescope(s)
Proposal gets accepted after peer review
Astronomer travels to observatory to spend many of his own nights collecting data
Astronomer takes the time to reduce and analyze his own data
Astronomer writes a paper(s) saying, "Hey - look what I did!"
(Sometimes) astronomer writes a proposal for further funding based on the merits of this work
This procedure is inefficient in that you sometimes get multiple people who are not working together, doing the same project on different telescopes. If I collect a bunch of data in one part of the sky, try to use it but don't actually get around to finishing and publishing a paper, and then archive it locally, nobody in the world knows that the data exists. So now if someone else wants to do the same project, they go to the telescope and recollect the same data. In other words, there's no central log of who's done what when it comes to individual observing.
P2P could be useful to remedy this. The problem is that astronomers tend to be very proprietary about their data. Sometimes research and publishing can be very competitive, and you don't want to give the competition an edge when it could mean that they publish a paper on a particular topic before you and reap the rewards, or get funding when you don't. So I think that most astronomers would share their data openly in a P2P network only after they were completely finished using it, and some would never do so.
The difference with the data sets being accessed by the proposed Virtual Observatory is that the people who create those sets typically get their funding with a stipulation that the data be publically accessible some time after the work is finished. They're not allowed to keep it proprietary even if they'd prefer to do so for competition reasons.
I got a perfect score on my breathalizer test, but I don't go around bragging about the 1.0
The other day I was using my overclocked, water-cooled Linux PS2 to write some assembly code to automatically record ST:TNG while I'm out seeing TTT on November 18th. I knew it was going to take a while, so first, I used vi to write a Perl script to have my NeXT workstation brew a fresh pot of java every 30 minutes using the Mr. Coffee clone that I built out of legos. Everything was going fine for a while, but then I started thinking about M$, the RIAA, the MPAA, the DMCA, and all those goddamned emacs users, and I found my blood boiling. So I tried playing a little Q3 to get my agressions out. But despite being l337, I was getting fragged badly because the ping on my 802.11b network was too high. So I gave up and settled down in front of my plasma TV to watch Babylon 5.
As was pointed out above, beta particles (electrons) can be easily stopped with thin sheets of metal which introduce large electrical interaction cross-sections. Alpha particles are too large to penetrate the skin to a significant depth and are only dangerous if ingested.
When I was a physics TA in college, we worked with radioactive pellets for some labs, and I was told that I actually had to tell the students that they 'should not eat the radiation sources'. I'm sure several of them would have tried if I hadn't warned them...
Why not? What are you going to do with a radioactive lump of stuff? I suppose you could try to choke someone with it or shoot people with beta particles...
This isn't the same sort of material that gets used in nuclear weapons; it's just isotopic material which decays with a characteristic timescale so that a steady stream of particles shoot away from it. You can use the momentum imparted by these particles to power a small generator - sort of like water turning a turbine in a dam or something (not exactly, but you get the picture...).
Adding sales tax would suck, but it wouldn't prevent me from shopping online.
Basically, at a given orbital energy, or velocity, and object can orbit at a certain distance from the central mass (the Sun in this case). If it speeds up, it has to move to a smaller orbital radius. If it slows down, it moves to a larger orbital radius. In this case, it sounds like the following may be happening:
(1) The asteroid is moving faster than the Earth, and so travels in a slightly lower orbit. When it gets to one Lagrange point, it will slightly overrun it, and the Earth's pull will send it to a higher orbit, stealing some of its kinetic energy. It then slows down and the Earth speeds away from it.
(2) The now slower-moving, higher-orbiting asteroid moves backward with respect to the Earth, until the Earth catches up to it until it overruns the other Lagrange point. When that happens, the Earth pulls it into a lower, more energetic orbit, and it proceeds to speed away from the Earth.
(3) go back to #1 and repeat.
During the brief time that the Earth's influence on the asteroid is greater than that of the Sun, the asteroid technically becomes a satellite of the Earth.
I could be wrong about all this, but at first read, this was how I interpreted things...
No doubt there are lots and lots of big-a$$ objects in the Kuiper belt. More will be discovered in time.
For something like Powers of Ten, as others have said, it's easiest to just use a photo of another spiral galaxy which we presume looks similar to what we would see if we could photograph the Milky Way from outside of it. We can do a pretty good job of finding an external "twin" galaxy, because there are a ton of them to choose from, and we have a good idea of what our own galaxy is shaped like.
"Powers of Ten" is definitely a classic science video, and the zoom effect is pretty good considering that it was made in 1968. Some of you may have seen "Cosmic Voyage", which is an IMAX film that came out a few years ago, narrated by Morgan Freeman. It's a bit more expansive in subject material than Powers of Ten, but it also contains a similar continuous zoom from the Earth out to a distance which shows the large-scale structure of the universe, and then back down to microsopic scales. This one is computer-generated. It's very cool. The video is available for sale if anyone's interested, and I think some IMAX theaters (especially ones in science museums) still show it.
Yeah, yeah. Nano-techno sunscreen and hair dye blah blah blah. Where are the freakin' robots already?!?
I have to agree. During the time I lived in California, it seemed (probably just due to faulty memory) like most of the earthquakes occurred at night, and I would generally not even wake up unless they registered maybe 5.5 or so. I never heard about real earthquake damage until the Loma Prieta quake of 1989. I lived in Los Gatos at the time - just a few miles from the epicenter. That one scared the bejesus out of people. Damage, loss of life... it was no fun at all. Anyway, a 5.2 shouldn't matter in California; it might matter someplace like Mexico City. To a Californian, a 5.2 is just a cheap substitute for a kid's amusement park ride - a mild, momentary thrill. Your biggest concern is not spilling your cappucino. Still - I'm glad to hear that people (at least a few /.ers) are okay.
'Legend' is probably right. If I recall correctly, that quake occurred somewhere around 5:00pm, so school would have been out. Still, it makes a good story, so I won't tell anyone if you won't...