Cancer Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings Neptune is in Aquarius, setting rather before Mercury now. I guess that technically makes it a morning-sky object. Quote Link to comment Share on other sites More sharing options...
death tribble Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings What I am seeing is a night sky object, visible at the same tiime as Venus and Jupiter without there being any stars out. So what planet is it ? Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings If you watch it for several minutes continuously, does it move? Quote Link to comment Share on other sites More sharing options...
tkdguy Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings Neptune is in Aquarius' date=' setting rather before Mercury now. I guess that technically makes it a morning-sky object.[/quote'] Thanks. With Pluto's demotion, Neptune is the only planet I haven't seen. I may have, since I was looking in the general area with my telescope years ago. Then a plane flew into view and blinded me with its lights. True story. Quote Link to comment Share on other sites More sharing options...
L. Marcus Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings "I used to be an astronomer like you, but then I took a searchlight to the eyes." Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings I believe it. I had a bright satellite pass 5 arcseconds from a faint star I was guiding on (putting it down a one-half-by-1.5-arcsecond aperture) while doing my thesis observations. Would have ruined about three hours worth of work had it happened. And there's a famous story about how for a while the best meteor spectrum yet published was one that flashed across the aperture while someone was guiding on a faint quasar. The meteor was so bright it saturated the image intensifier so strongly the afterglow was there for a couple of hours, and that could be done was take that meteor spectrum and publish it. Quote Link to comment Share on other sites More sharing options...
Old Man Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings Yeah, when I was working on developing comet lightcurves two decades ago, I got to hear several long tirades about satellite flybys. For some reason, astronomers get irritated when a satellite flies through the picture during the scope time that they waited months or years to get. Cosmic rays also seemed to have an annoying tendency to hit the detector right where the observed object was, too. Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 29, 2012 Report Share Posted March 29, 2012 Re: Musings on Random Musings Most "cosmic rays" are now understood to be radioactive decays (supposedly mostly silicon-32) within the detectors. Where the chip manufacturer picked up their sand matters, as it happens. When the recoil fragments all move in the plane of the detector, it makes for a long, extended mess. Quote Link to comment Share on other sites More sharing options...
Old Man Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings That explains a lot, actually. Huh. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings "I used to be an astronomer like you' date=' but then I took a searchlight to the eyes."[/quote'] The goggles -- the didn't do anything? Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings While it is often touted that nuclear power produces no CO2, I am confident that it does produce water vapor since (afaik) water is always the method used to cool the return flow to the reactor. I wonder if any study has been done to "equate" the total emissions of a nuclear plant vs the total emissions of a non-nuclear plant, and see if nuclear really is better* than non. *From what little (and it is not a lot) I have learned, water vapor is a much greater greenhouse gas than CO2 is, but comes out of the air much more readily (rain). I am not up on post-1980 reactor designs, but I was under the impression that there's always at least two fully closed loops between the fissile stuff and the environment. There's the coolant circulating in a closed loop, which passes energy through a heat exchanger to another closed loop, which is what gets run through the turbine (that is coupled by a shaft to the armature and turns the coil in the generator which does the Faraday's Law thing and makes electromotive force). There are a variety of coolants in use now (water, gas, liquid sodium, some other stuff at least under consideration), but I think the secondary loop is invariably water. But even that second loop is closed (I think to maintain efficient operating pressure, rather than a need for more radiation or chemical safety). By that time, in "normal" operations, you're down to the thermodynamically-inevitable waste heat, and that will make some water vapor no matter what you are doing to heat up the working fluid sent through the turbine. So any act of electricity generation will produce waste heat and dump that into the environment (and hence boost the water vapor content of the atmosphere through increased evaporation), and nuke plants are not excepted from that. But if that really bothers you, you should be making NO generation plants at all, rather than building another fossil fuel plant; the waste heat is something that is thermodynamically unavoidable and your only option to avoid that is to build nothing. And that is a different argument, I think, than the one you indicated interest in. Quote Link to comment Share on other sites More sharing options...
Xavier Onassiss Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings Thanks. With Pluto's demotion' date=' Neptune is the only planet I haven't seen. I may have, since I was looking in the general area with my telescope years ago. Then a plane flew into view and blinded me with its lights. True story.[/quote'] I was gonna say I wasn't aware that Uranus was a naked-eye object but there's really no way that statement doesn't come out sounding all kinds of wrong. Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings Uranus is borderline naked-eye visible under optimal conditions. That means you have more or less no hope of being sure you saw it even if those conditions held and you were looking in the right place. I've only seen it in a Pretty Big Telescope. With a telescope and a good finding chart it is reasonably easy to see. It had been spotted a number of times before Herschel's discovery, but not recognized as anything but another star. Similarly, Galileo sighted Neptune with his telescope when it was in conjunction with Jupiter in 1612 -- it is convincingly present as a star in some of his drawings of Jupiter and the starfield it was in at the time -- but he did not recognize it as a planet (his telescope couldn't resolve the disk of the planet). Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings I am not up on post-1980 reactor designs, but I was under the impression that there's always at least two fully closed loops between the fissile stuff and the environment. There's the coolant circulating in a closed loop, which passes energy through a heat exchanger to another closed loop, which is what gets run through the turbine (that is coupled by a shaft to the armature and turns the coil in the generator which does the Faraday's Law thing and makes electromotive force). There are a variety of coolants in use now (water, gas, liquid sodium, some other stuff at least under consideration), but I think the secondary loop is invariably water. But even that second loop is closed (I think to maintain efficient operating pressure, rather than a need for more radiation or chemical safety). By that time, in "normal" operations, you're down to the thermodynamically-inevitable waste heat, and that will make some water vapor no matter what you are doing to heat up the working fluid sent through the turbine. So any act of electricity generation will produce waste heat and dump that into the environment (and hence boost the water vapor content of the atmosphere through increased evaporation), and nuke plants are not excepted from that. But if that really bothers you, you should be making NO generation plants at all, rather than building another fossil fuel plant; the waste heat is something that is thermodynamically unavoidable and your only option to avoid that is to build nothing. And that is a different argument, I think, than the one you indicated interest in. Oh, I fully understand that adding energy to the environment, no matter the source, will add heat to the environment. I was just musing about the relative emissions of each kind of plant. I'm not sure if nuclear plants have ever been touted as "emission free", but if so, I think that is incorrect. That is all. Quote Link to comment Share on other sites More sharing options...
Old Man Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings Oh' date=' I fully understand that adding energy to the environment, no matter the source, will add heat to the environment. I was just musing about the [i']relative [/i]emissions of each kind of plant. I'm not sure if nuclear plants have ever been touted as "emission free", but if so, I think that is incorrect. That is all. The real emission that nuclear plants give off is radioactive waste. They may also give off some waste heat and a little steam, but these are negligible compared to the energy being generated. Quote Link to comment Share on other sites More sharing options...
Logan D. Hurricanes Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings The real emission that nuclear plants give off is radioactive waste. They may also give off some waste heat and a little steam' date=' but these are negligible compared to the energy being generated.[/quote'] Radioactive materials not being used to create super powers, that's the real waste. Quote Link to comment Share on other sites More sharing options...
Cancer Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings Radioactive materials not being used to create super powers' date=' that's the real waste.[/quote'] Yeah, Super Dead Man isn't much of a power. Quote Link to comment Share on other sites More sharing options...
Enforcer84 Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings Yeah' date=' Super Dead Man isn't much of a power.[/quote'] Worked for Boston Brand. Quote Link to comment Share on other sites More sharing options...
Enforcer84 Posted March 30, 2012 Report Share Posted March 30, 2012 Re: Musings on Random Musings My acting department head just popped in and says she is thinking of going to Emerald City Comic Con tomorrow in costume as Poison Ivy. Does she need a gardener? *ouch* Quote Link to comment Share on other sites More sharing options...
tkdguy Posted March 31, 2012 Report Share Posted March 31, 2012 Re: Musings on Random Musings Uranus is borderline naked-eye visible under optimal conditions. That means you have more or less no hope of being sure you saw it even if those conditions held and you were looking in the right place. I've only seen it in a Pretty Big Telescope. With a telescope and a good finding chart it is reasonably easy to see. It had been spotted a number of times before Herschel's discovery, but not recognized as anything but another star. Similarly, Galileo sighted Neptune with his telescope when it was in conjunction with Jupiter in 1612 -- it is convincingly present as a star in some of his drawings of Jupiter and the starfield it was in at the time -- but he did not recognize it as a planet (his telescope couldn't resolve the disk of the planet). My telescope isn't a large one, but it's pretty good (or was, until I accidentally damaged it). It's an older model, though, so they don't make replacement parts. It normally wouldn't see much use anyway, as my neighbors are really boring. Quote Link to comment Share on other sites More sharing options...
death tribble Posted March 31, 2012 Report Share Posted March 31, 2012 Re: Musings on Random Musings If you watch it for several minutes continuously' date=' does it move?[/quote'] I am using the naked eye and it appears along with Venus and Jupiter with no other stars visible. And np I did not stand around looking up at it and the other two. What I can say is that when I can see the other two clearly, I then look to my left or west and you see this object which is faint. But it is a bit of a way over. Quote Link to comment Share on other sites More sharing options...
James Gillen Posted April 1, 2012 Report Share Posted April 1, 2012 Re: Musings on Random Musings I am using the naked eye and it appears along with Venus and Jupiter with no other stars visible. And np I did not stand around looking up at it and the other two. What I can say is that when I can see the other two clearly, I then look to my left or west and you see this object which is faint. But it is a bit of a way over. The visibility of Uranus depends greatly on one's angle. JG Quote Link to comment Share on other sites More sharing options...
Old Man Posted April 1, 2012 Report Share Posted April 1, 2012 Re: Musings on Random Musings I am using the naked eye and it appears along with Venus and Jupiter with no other stars visible. And np I did not stand around looking up at it and the other two. What I can say is that when I can see the other two clearly, I then look to my left or west and you see this object which is faint. But it is a bit of a way over. You are definitely not seeing Uranus, which would be below and to the right of the sun, and so close to it that I don't see any way you could actually observe it. Depending on how far over 'a way over' is, I suspect you're seeing Aldebaran, Betelgeuse, or Sirius. I think the latter is most likely--almost a direct line leftward of Venus right now, and slightly higher up in the sky. Alternatively, it's possible you saw the ISS or Hubble, either of which can be quite visible to the naked eye under the right conditions. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted April 1, 2012 Report Share Posted April 1, 2012 Re: Musings on Random Musings You are definitely not seeing Uranus, which would be below and to the right of the sun, and so close to it that I don't see any way you could actually observe it. Depending on how far over 'a way over' is, I suspect you're seeing Aldebaran, Betelgeuse, or Sirius. I think the latter is most likely--almost a direct line leftward of Venus right now, and slightly higher up in the sky. Alternatively, it's possible you saw the ISS or Hubble, either of which can be quite visible to the naked eye under the right conditions. But clearly not a planet as they practically zip across the sky. Didn't know Hubble was visible, but I have seen the ISS. Quote Link to comment Share on other sites More sharing options...
SteveZilla Posted April 1, 2012 Report Share Posted April 1, 2012 Re: Musings on Random Musings My acting department head just popped in and says she is thinking of going to Emerald City Comic Con tomorrow in costume as Poison Ivy. I didn't know you were in charge of a whole department of thespians. And if she goes, you *have* to take pictures! Quote Link to comment Share on other sites More sharing options...
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