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Valiant Dancer
Forum Goalie
USA
4826 Posts |
 Posted - 01/07/2002 : 08:29:14 [Permalink]
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Well, I'll try to answer everything that I remember. (Some of this stuff I never knew.) Bear in mind, I'm a computer geek first.
A) One night Lisa and I were talking about the stars, as usuall, and she was trying to explain to me why the stars don't really move. But the thing is is that I still don't get it. So here's my question: Why, from the humans eye, it seems like the stars don't move? And if they do, how come we can't tell??
We can't visually tell than stars move because they are so far away. If you've ever been out in a plains state, you'll notice that cars near the horizon don't appear to be moving fast at all. When it whizzes past you, it's speed becomes apparent. This is true of stars.
B) What are luxons, muouns, and tachyons, and what is the difference between them?
C) What is a dwarf star, and what different types of them exist?
A dwarf star is smaller than most stars. The ones I know of are brown and white.
Brown dwarfs are very small about 40 jovian masses. (I could be wrong about how many masses but it's less than 100.) They have enough mass to start nuclear reactions in its core through gravitation but never burns very bright.
White dwarfs burn much hotter than brown dwarfs.
D) How do stars form?
Clouds of gas gather by gravity until enough matter falls into the center and becomes compressed enough for nuclear fusion to start.
E) What is the differecne between the goecentric and heliocentric theories?
Geocentric places the Earth at the senter of the universe. (later proven wrong)
Heliocentric places the sun in the center of the solar system/universe. It is more accurate than the geocentric model.
F) Where does the sun get its energy?
From the nuclear fusion in it's core. It is making helium out of hydrogen currently.
G) What is the inversesquare law?
H) What are Kepler's Laws?
These are laws of planetary motion proposed by Johnannes Keppler based on his own observations and observations made by Tycho Brahe.
I) What are blue and red shifts, and what is the difference between them?
Has to do with motion how light rays become compressed. It is sort of like the laws of doppler shift. When a freight train is moving toward you and it blows it's horn, the horn has a higher perceived pitch because the sound waves are bunched up. Once it passes, the horn has a lower percieved pitch because the waves are more stretched out. It is the same way withht. Light is wavelength based for color. Red shift is when the object is moving towards you as the light wavelength becomes compressed. Red has a higher frequency than blue. The faster an object moves towards you, the higher the red shift. Converse for blue.
J) What are cosmic rays?
K) What is a singularity?
The theoretical center of a black hole. It is matter compressed so densely that it prevents light from escaping.
L) What is an elliptical galaxy?
It is a galaxy which looks like an elipse. It is one of the standard galaxy types.
M) What is an irregular galaxy?
A galaxy which does not look like a spiral or eliptical galaxy. Usually due to a close encounter with a much more massive galaxy which started to tear it apart.
N) What is a spiral galaxy?
A galaxy that looks like our own. It usually has arms that slowly circle. It almost looks like water going down a drain.
O) What is magnitude? And what is it in astonomical terms?
P) What is the difference between the photosphere and the chromosphere?
Q) What is the difference between periapsis and apoapsis?
R) What is a neutrino?
S) How are stars classified?
T) What is the ergosphere?
U) What are interstellar dust grains?
V) What is a pulsar?
When a star goes supernova, the core is exposed. Pulsars have a section of themselves which give off x-rays. as the core spins, the pulsar sends out it's x-rays like a searchlight. The younger the pulsar, the faster it's spin.
W) What is the Hubble Constant?
X) What is the sun made of?
Hydrogen and helium. When the sun runs out of hydrogen in about 3 billion years, it will start converting heilum to a heavier element. (this will start the death cycle for our star.)
Y) What is a supernova?
When a large star (at least 5 solar masses) reaches the end of it's life, it can no longer support it's outer shell by the fusion reactions going on in it's core (The energy from the fusion reactions prevents the star from collapsing. As the elements being fused become heavier, the less force is exerted outward.), it collapses. When the star collapses, it gets to a point where the core is able to push back enough and it violently explodes.
Z) What is a nova?
A car made by Chevrolet. See rustbucket.
Seriously, I've seen nova and supernova used interchangably. I'm not sure about this one.
1) What is the difference between a meteroroid, a meteor, and a meterorite?
They are all terms for space rocks.
A meteroid is a rock in space.
A meteor is one entering the earth's atmosphere.
A meteorite is a meteor which survives long enought to hit the ground.
2) What is Doppler shift?
See my answer to red/blue shift. Doppler refers to sound.
3) What are inner and outer planents, and how do they differ?
The inner planets are rocky. They are closest to the sun. The outer planets are gassy. They start at Saturn and go out from there. In this case, Pluto is not a true outer planet because it doesn't meet this criteria.
4) What are planetary atmospheres?
they are gasses near the planet's surface. The thickness varies. Mercury and (probably) Pluto don't have atmospheres.
5) Why do stars appear to "twinkle"?
The atmosphere is very turbulent. The waves of atmosphere cause very distant objects to appear to get brighter or dimmer.
6) What is half-life?
The amount of time that passes before half of a radioactive element decays towards a less radioactive element.
7) What is a coma?
The "head" of a comet.
8) What is the difference between Apparent Time, Mean Time, Sidereal Time, and Universal Time?
9) What is an aurora, and what are the names of some of the famous ones?
An arorae is radiation in the magentic sphere around our planets. When a solar storm blows out high energy radiation toward our planet, for some reason, it collects near the poles and becomes visible. There are only two. The Arora Borealis for the northern hemisphere and the Arora Australious (sp) for the southern hemisphere.
10) What is a binary star?
Two stars orbiting one another.
11) What is the event horizon?
The part around the black hole where light can no longer escape.
12) What is a Cepheid?
13) What is a nebula?
Clouds of gas. These often times will be where stars form. Or this is where they have died.
Hope this helps. You keep this up, and you'll learn something. (maybe me, too)
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Trish
SFN Addict
USA
2102 Posts |
Posted - 01/07/2002 : 14:37:34 [Permalink]
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quote:
Megan, I may take a swing at some of your other questions later. Sorry to step on your toes, Trish, but I thought it was better to correct the errors; it's so easy to get a misconception stuck in one's head (I should know, I have a bunch of them in there!)
Donnie, I would be glad that you would correct me.
You are of course correct that loud was the improper term when dealing with doppler effect. Understood regarding sound and light - but the concept of the train I think is the easiest explanation, since we can actually go out and experience it for ourselves. It's not that far - once you understand frequency in sound to the conecption of frequency in light.
I don't know how I could forget dear little Pluto and Charron sitting way out there.
Thank you for the correction on stars and twinkling. However, I would ask how come the reflected light of planets then does not twinkle if it's atmospheric disturbances. It would seem that this would also affect this type of light. I would really appreciate an answer. (I'm not trying to be sarcastic or rude - I would really like to know why.)
Now Donnie - can you help me fix my little diagram showing about measuring frequency? Please?
See Megan, this is why you should verify information for yourself from somewhere that has qualified people to answer these questiongs. 
There is no better demonstration of the folly of human conceits than this distant image of our tiny world. It underscores our responsibility to deal more kindly with one another, to preserve and cherish the pale blue dot, the only home we've known. Sagan |
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Donnie B.
Skeptic Friend
417 Posts |
Posted - 01/07/2002 : 14:50:52 [Permalink]
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quote:
Thank you for the correction on stars and twinkling. However, I would ask how come the reflected light of planets then does not twinkle if it's atmospheric disturbances. It would seem that this would also affect this type of light. I would really appreciate an answer. (I'm not trying to be sarcastic or rude - I would really like to know why.)
Planets don't twinkle because they're relatively close by, so they show a disk rather than a point source of light. That means that they are less affected by the atmospheric disturbances... not totally unaffected, just less so.
quote:
Now Donnie - can you help me fix my little diagram showing about measuring frequency? Please?
Sad to say, I don't have a perfect solution. Oddly enough, though, when I opened your original post in a reply-with-quote window, there was your diagram, pretty much the way you wanted it to be!
I think the software that displays our posts is trying to be "helpful" by removing the leading spaces, or perhaps by replacing multiple spaces-in-a-row with a single space. Maybe you need to put in some other character instead of a space, but that might look pretty ugly.
By the way, I noticed quite a few good replies to Megan's questions over on the BABB; so I'm not going to duplicate the effort by answering them again here.
-- Donnie B.
Brian: "No, no! You have to think for yourselves!" Crowd: "Yes! We have to think for ourselves!" |
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Trish
SFN Addict
USA
2102 Posts |
Posted - 01/07/2002 : 15:04:27 [Permalink]
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quote:
Planets don't twinkle because they're relatively close by, so they show a disk rather than a point source of light. That means that they are less affected by the atmospheric disturbances... not totally unaffected, just less so.
Yeesh! You say this and the entire lecture on why stars twinkle came right back to me. Everything, down to the hill we were sitting on and freezing while we sat there. Point source v disc. Damn.
Figured she get better answers at BA.
There is no better demonstration of the folly of human conceits than this distant image of our tiny world. It underscores our responsibility to deal more kindly with one another, to preserve and cherish the pale blue dot, the only home we've known. Sagan |
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Donnie B.
Skeptic Friend
417 Posts |
Posted - 01/07/2002 : 17:28:44 [Permalink]
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LOL!
Memory is a funny thing sometimes... 
-- Donnie B.
Brian: "No, no! You have to think for yourselves!" Crowd: "Yes! We have to think for ourselves!" |
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Lisa
SFN Regular
USA
1223 Posts |
Posted - 01/07/2002 : 19:52:40 [Permalink]
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Great night tonight!! Clear sky and the milky way is beautiful. Megan and I found Jupiter (w/moons), Saturn, and the Orion Nebula. We had a few problems after that. We live in a place called "Pine Cliff", so as the name implies, we can also see lots of trees. Ed and I have lots of camping trips planned with Megan's family this summer, so we'll probably do better on a mountaintop somewhere.
Lisa
If you're not living on the edge, you're taking up too much room. |
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Stygma
New Member
36 Posts |
Posted - 01/07/2002 : 23:48:08 [Permalink]
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| Wow, that's a nice find. Bet she was thrilled at the nebula. Best of luck on any other gazes. RFTS |
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Donnie B.
Skeptic Friend
417 Posts |
Posted - 01/10/2002 : 20:46:13 [Permalink]
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Hmmm... the BABB seems to be down... guess I'll go to bed.
-- Donnie B.
Brian: "No, no! You have to think for yourselves!" Crowd: "Yes! We have to think for ourselves!" |
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Donnie B.
Skeptic Friend
417 Posts |
Posted - 01/12/2002 : 11:16:10 [Permalink]
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Hoo boy...
What is it about the BA site that attracts them?
Once Phil disposed of P*p*r and various other morons (yes, Gorgo, I used the word moron), I thought we could enjoy a nice quiet bulletin board. But alas, the peace was not to last...
Can anybody make out what "Emperor" is saying? Other than "buy my e-book"?
General question: how come every one of these bozos says, at some point and in some words, "You're all a bunch of jerks and I'm going away and never coming back!", then proceeds to start another half-dozen incomprehensible threads? Including, of course, one that says "everybody here is a feeble-minded, brainwashed dupe of the establishment who doesn't deserve to know the Great Truth I've discovered while smoking crack in my garage".
Oh Lard, spare us!
-- Donnie B.
Brian: "No, no! You have to think for yourselves!" Crowd: "Yes! We have to think for ourselves!" |
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Chippewa
SFN Regular
USA
1496 Posts |
Posted - 01/12/2002 : 12:30:10 [Permalink]
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quote:
Hoo boy...
What is it about the BA site that attracts them?...
I've sailed trough the various threads launched by Emperor, and resisted an urge to answer - (though I'm cheering for Grapes of Wrath.) He has asked repeatedly if Emperor also wrote the positive "review" on his website of his own "book." The review is certainly in the same style of run-on sentences and excessive rhetoric.
In my opinion, from Emperor's first rude reply to a question, he seems to be in the "fill in monikers of your favorite former banned posters here" camp, who's mentality seems to be: "all scientists are conspiring - I have the absolute truth - questioning me is an attack on me."
The main characteristic is the "just explain it to me - if you dare" syndrome. Various folks then attempt to explain a theory and if it's in an analogy, it's mocked and taken literally, if it's technical, it's also mocked and implied to be part of a secret society of math endowed scientists ploting against "common sense." If a book is recommended by someone, an irrational resonse follows along the lines of: "I don't have time to read books!" (Emperor seems to have cornered the market here.) Its clear he's there to try to sell his own book and doesn't want to discover anything, though he's not quite a troll in that he answers back but often rudely.
See how many words I've wasted on this guy? I could put these words to better use elsewhere! :-) That's why I don't think I'll answer him on the BABB. (I wish he'd stay in the "Against the Mainstream" side of the board instead of posting his "nagging questions" also on the "General Astronomy" side - very silly - but at least there's symmetry.) :-)
"I'd never join an organization that would have a man like me as a member." |
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Donnie B.
Skeptic Friend
417 Posts |
Posted - 01/12/2002 : 17:01:01 [Permalink]
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Hi, Chippewa,
I agree with your analysis. I guess my question was mostly rhetorical; I was just feeling frustrated.
The "Emperor" type is so annoying and irritating to me that I end up sending wiseass replies and doing nobody any good. So I came over here to let off steam.
By the way, it seems Phil has moved all his "nagging" threads to "ATM" where they belong, and send him a stern warning to boot.
-- Donnie B.
Brian: "No, no! You have to think for yourselves!" Crowd: "Yes! We have to think for ourselves!" |
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Chippewa
SFN Regular
USA
1496 Posts |
Posted - 01/12/2002 : 20:48:33 [Permalink]
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Well Donnie,
Looks like Emperor has left the building! He signed off (01/12/02) in a post calling Phil's website "fantasy land," and claiming that he will be remembered when all theoretical and applied physics is proved wrong. What an ego! Unfortunately egos like that sometimes say "good bye!" - (slamming door) and then come back tomorrow with "and furthermore..."
Fortunately, his approach to various astronomy topics negates any interest I have in responding, though the topics themselves - black holes, GR, etc...are fascinating without his opinions.
"I'd never join an organization that would have a man like me as a member." |
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James
SFN Regular
USA
754 Posts |
Posted - 01/13/2002 : 16:49:10 [Permalink]
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quote:
Looks like Emperor has left the building! He signed off (01/12/02) in a post calling Phil's website "fantasy land," and claiming that he will be remembered when all theoretical and applied physics is proved wrong.
I know that we won't remember him when Phil has deleted his threads.
I, personally, cannot wait until Phil bans him, like he did with Mifletz. 
"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your common sense." -Buddha |
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Dog_Ed
Skeptic Friend
USA
126 Posts |
Posted - 01/13/2002 : 17:15:30 [Permalink]
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Ho ho, I agree with Chip...came to the same conclusion about "Emperor," who is of course John Reyes. I started another topic dealing specifically with Reyes before I caught up on this thread. I do encourage those with the bile to vent to visit the forum on Reyes' site and post comments (I put a link in the other thread).
--Don
"Even Einstein put his foot in it sometimes" |
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Piltdown
Skeptic Friend
USA
312 Posts |
Posted - 01/14/2002 : 02:14:11 [Permalink]
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quote:
Ho ho, I agree with Chip...came to the same conclusion about "Emperor," who is of course John Reyes. I started another topic dealing specifically with Reyes before I caught up on this thread. I do encourage those with the bile to vent to visit the forum on Reyes' site and post comments (I put a link in the other thread).
--Don
"Even Einstein put his foot in it sometimes"
I need to get back to posting at the BABB. I just went over there and caught up a little. Yikes! This Reyes/Emperor person makes even P*p*r seem the soul of reason, not to mention literary technique.
My knowledge of astronomy, cosmology in particular, is pretty limited, so my earlier participation at BABB was mostly concerned with the moon hoax. No great astronomical knowledge is required to demonstrate that the landings really happened and the hoax is impossible. I'm out of my element with quacks like Emperor. My main reason for doubting them is really my knowledge of how science works, and the impossibility of 300 year's worth of astronomers conspiring to hide each other's errors.
Abducting UFOs and conspiring against conspiracy theorists since 1980. |
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