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Planetary System Similar to Sol Discovered
Anonymous Coward writes: "The Washington Post is carrying its own copy about a planetary system very similar to Sol in the Big Dipper. 47 Ursae Majoris has at least two large gas giants in circular orbits, similar to many of Sol's satellites, and the possibility exists for smaller, currently undetectable rocky planets closer to the primary. Circular orbits are less common than highly elliptical orbits, and are more promising. Read the whole article to find out why."
Tell that to Jon Johansen in Norway who contributed in making DeCSS.
- Steeltoe
http://www.debunkingskeptics.com/
a feature currently suggested on sourceforge for slashcode is to be able to filter out all funny comments... that'd solve your problem
There are a lot of things that happen faster than light. You can even demonstrate one to yourself right now.
Go outside. Shine a flashlight into the sky and sweep it back and forth. At some point Out There, your spot of light will be moving from side to side faster than the speed of light. Do the geometry if you want to figure out how far away that is.
The problem is this: there is no way to exploit anything like that into an information-transmitting system. That quantum interconnected stuff you alluded to is the same way. It's cool, but ultimately useless.
We're not going to trick physics that easily.
Of course, this isn't what you do. You say.
"Hi, we think we have detected someone who might be able to receive this message. Here are 90 years of transmissions from our encyclopedias, archives, libraries, etc., with lots of redundancy, various frequencies etc. etc."
90 years later, if all goes well, you start receiving replies like
"Hey, good to talk, we've decoded your language primers. Here are our encyclopedias etc."
Then a few months later
"Based on what you've sent so far, we'd like to hear more about fly fishing, barbecue cookery and string theory (or whatever). We're also starting to skip the basic physics in our encyclopedias where it matches up with what you're telling us you already know."
If you haven't already sent the requested info, you slip it in when the question arrives.
It's not exactly a conversation, but if both sides are willing, you can learn a lot about one another in a couple of centuries.
I don't think this is an issue for a couple of reasons.
First of all, gas giants are massive, and hence the satellites will orbit pretty quickly. Io is about the same distance from Jupiter as the moon is from the earth, and its orbital period is about two days. It would only be in eclipse for a few hours. And that would only affect the Jupiter-facing side. The other side would have a normal day/night cycle.
Secondly, the amount of time spent in the gas giant's shadow is dependent on the planet's axial tilt. Jupiter is at 3 degrees, so the Galilean satellites go into eclipse pretty much on every orbit. (Callisto may be an exception near the solstices). Saturn's tilt is 27 degrees, so the only time a satellite would go into eclipse is if it's close to the equinox, or if it's really close, in which case it would be torn up into rings.
I would worry about the radiation around gas giants. If a satellite is close in, it would get bombarded by a lot of radiation, unless it had a strong magnetic field. If it was far away, it would rotate slowly and I don't know how that would affect the day/night temperatures.
Another thing to worry about is getting hit by meteors - the gas giant has a huge gravity well and will be pulling stuff towards it all of the time. Catastrophic impacts probably wouldn't be too uncommon.
Only in the world of science fiction and dilber cartoons. The idea of "molecular bifurcation communication" in all of its forms is based on a misinterpretation of J.S. Bells' theorom (referenced in the Dilbert cartoon where he tries to make one, sorry I don't have the date).
Bells theorom losely states that it is possible to construct two particle systems -- two photon, two halves of a molecular decay, whatever -- in which the state of the system cannot be explained in terms of the state of part 1, and the state of part 2.. ie, there is some non-local correlation between them.
However, you can't actually *do* anything to one particle and have it affect the other. You can only see this correlation after you measure both particles, and compare their states -- which means you have to communicate over a "classical" channel first.
As for FTL travel/communication in general, I am not an expert in general relativity, and it is still actually an open question, but I don't believe that FTL communication will ever be possible.
"if you read this then you are gay"
Well, duh. You DID post it on Slashdot, did you not?
Lighten up.
Ultimately, nothing matters. 99.9999% of the things that occupy your day to day thoughts really don't amount to anything. In my opinion, this makes the things that don't matter much more important than the things you do. "The less meaning, the more meaning", if you are into that "and then he was enlightened" type koan crap.
The French have a word for that other existentialist/nihilistic crap, but I don't know how to spell it. Ultimately it doesn't matter.
That's one way of looking at things, or you could take the opposite approach - ferinstance, quite a bit of computer tech was developed specifically for NASA's moon push in the 60's - would we be talking today if not for space exploration? As to world hunger, it might not end it in the short term, but in the long term, who's to say it won't? If cheap space transport and effect terraforming can be developed (who knows if they can, but who really thought computers were possible a relatively short 150 years ago?) we've got two planets pretty close by, Mars & Venus, that would make great big-ass farms.
Mining other planets and asteroids has the potential to provide plenty of precious metals, and on the war front - a few extra planets to expand to could stop war quite easily - or make it 10 times as worse, but war isn't something that's going to be solved by us staying on planet either, and if anything I think the population constraints that living on just one planet provides are much more likely to cause war than anything. And of course there's species survival to think about... as a whole humans are more likely to survive indefinitely if we're on many different planets, cuz right now if we blow up this one, well, that's it. I'm sure any sci-fi hack can flesh this out better than I have, but since I'm up...
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Why should we bother wasting time exploring space when the world we live on is not perfect? You're right, it costs money, and there is not immediate gain to discoveries like this. However, there are several good reasons.
Firstly, I suggest you watch the show connections sometime. It's a wonderful show for history if nothing else. In it, the narrator shows how each invention or discovery led to others, building the very foundation of knowledge without which the current world you live in would not be possible. Many of the inventions in that chain were considered, at the time, to be useless. Impractical. A novelty at best. However, when applied with some other idea (or 2) from other people it blossomed into a very useful invention.
So how does this discovery help us? Directly, not at all. But indirectly, it may be very important. Remember the story within the last few days here on /. about those astronamers who were trying to prove that constants changed over time, and thus help string theory? If the advances made by others needing to look farther into space, for things exactly like this discovery, were not made, that may have never been possible.
Another reason we should do this is that it helps explore, discover, and explain our universe.
Societies are judged, from a historical standpoint, by the advancements they make for humanity. Think of what Rome is remembered for. The roads they made which allowed trade across great distances. The aquaducts, etc. These were made possible by taxes, just like NASA is today.
We have the ability to explore more of the universe than anyone in history. Does this mean we should do it to the exclusion of helping suffering in the world? No. But it does mean that if we have the ability, and resources, and do nothing with it, we will be holding back progress which could ultimately help humanity expand it's knowledge of the universe we live in. And personally, I am willing to give a few tax dollars to that.
Here's a thing not really talked about. If a moon of a large planet harbours life, they'd have to be orbiting in a perpindicular plane to the rest of the solar system to sustain it. Pretty unlikely. And if they weren't, they'd disappear behind the planet every 'night' for long periods. Hence, you've got a moon with huge long nights, freezing the planet, and long hot days. The only way round it is an incredibly fast orbit, which would stuff everything up. Am I missing something here?
toeslikefingers.com - because
Is that true? If so, how do we know?
Remember that the only way we can currently detect planets outside our own solar system is by their gravitational influence on the primary star, and the effect is right on the edge of what we can detect. We're seeing lots of massive gas giants in orbits that bring them close to their primaries because we can't (yet) detect anything else.
In our own solar system, the gas giants are in large circular orbits. If our solar system is typical, we're only seeing a small distorted sample of what's out there.