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Date: 19 Aug 2006 17:06:20
From:
Subject: Two Questions...
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Ok, These two questions are totally unrelated but I didn't want to take up two topics so...: 1. When a teacher at school was talking about how perfect the placing of earth was, the nerdy guy in the class said "ya, if it were a few inches closer to the sun, the glaciers would melt and destroy the earth, and if it were a few inches away, then we would freeze to death" I, actually knowing more and not usually showing it, pointed out that the earth alternated from ~90-96 million miles away from the sun every year and summer is actually further away than fall but... he said "no, if the orbit was a few inches off" and i didn't want to start a huge debate which would make me look like him but... I know that a tiny deviation like 6 inches in orbit must happen all the time... such as earthquakes and considering the mass of the moon, its orbit must move the earth a few miles every month so... how much deviation from orbit would it take for something catastrophic like a huge flood? 2. I have been interested in astronomy lately and I wondered what are the price ranges for telescopes? And are there any that you can sync with your computer and see digital images/ type in long. and lat. and it shows that part of the sky? Thank you ;-D
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Date: 19 Aug 2006 17:42:43
From: Starlord
Subject: Re: Two Questions...
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For the 2nd question, before thinking about buying one, read this first: Telescope Buyers FAQ http://home.inreach.com/starlord <wiiwiillwiin@gmail.com > wrote in message news:1156032380.292747.114700@75g2000cwc.googlegroups.com... > Ok, These two questions are totally unrelated but I didn't want to take > up two topics so...: > > 1. When a teacher at school was talking about how perfect the placing > of earth was, the nerdy guy in the class said "ya, if it were a few > inches closer to the sun, the glaciers would melt and destroy the > earth, and if it were a few inches away, then we would freeze to death" > I, actually knowing more and not usually showing it, pointed out that > the earth alternated from ~90-96 million miles away from the sun every > year and summer is actually further away than fall but... he said "no, > if the orbit was a few inches off" and i didn't want to start a huge > debate which would make me look like him but... I know that a tiny > deviation like 6 inches in orbit must happen all the time... such as > earthquakes and considering the mass of the moon, its orbit must move > the earth a few miles every month so... how much deviation from orbit > would it take for something catastrophic like a huge flood? > > 2. I have been interested in astronomy lately and I wondered what are > the price ranges for telescopes? And are there any that you can sync > with your computer and see digital images/ type in long. and lat. and > it shows that part of the sky? > > Thank you ;-D >
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Date: 20 Aug 2006 01:02:26
From: Sam Wormley
Subject: Re: Two Questions...
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wiiwiillwiin@gmail.com wrote: > Ok, These two questions are totally unrelated but I didn't want to take > up two topics so...: > > 1. When a teacher at school was talking about how perfect the placing > of earth was, the nerdy guy in the class said "ya, if it were a few > inches closer to the sun, the glaciers would melt and destroy the > earth, and if it were a few inches away, then we would freeze to death" There is a young assistant professor of physics at Iowa State University, Guillermo Gonzalez and with Jay Richards of The Discovery Institute, coauthored a book titled, "The Privileged Planet: How Our Place in the Cosmos is Designed for Discovery". The book devotes a whole chapter trying to knock off the Copernican Principle. I gave my copy of the book to Fritz Franzen--cautioning that he should not read it if he didn't want to raise his blood pressure. Some weeks later Fritz wrote a scathing "book report" to me by email. He was disgusted! Concerning the chapter on the Copernican Principle, he wrote, "The authors set up a straw man imbuing the Copernican Principle with a number of ridiculous attributes that they then disparage and in so doing imply that they are destroying a scientific theory. Irritating rubbish!" Vic Stenger--gives a review of "The Privileged Planet" for "Reality Check" in Skeptical Briefs, September 2005. http://www.colorado.edu/philosophy/vstenger/Briefs/Priv.htm "Of course, Gonzalez and Richards are entitled to their views, but this tale provides yet another illustration of the stealthy nature of the strategy behind the Discovery campaign to "renew science and culture." The Privileged Planet represents a new, cosmic wedge in the Discovery arsenal (why can\u2019t one have an arsenal of wedges?). It joins with intelligent design as another form of stealth creationism, claiming to be science but motivated by religion. We can only wonder why a group of people who claim a special pipeline to the source of truth and morality feel they can't be honest with the rest of us".
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Date: 20 Aug 2006 00:33:41
From: Sam Wormley
Subject: Re: Two Questions...
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wiiwiillwiin@gmail.com wrote: > Ok, These two questions are totally unrelated but I didn't want to take > up two topics so...: > > 1. When a teacher at school was talking about how perfect the placing > of earth was, the nerdy guy in the class said "ya, if it were a few > inches closer to the sun, the glaciers would melt and destroy the > earth, and if it were a few inches away, then we would freeze to death" > I, actually knowing more and not usually showing it, pointed out that > the earth alternated from ~90-96 million miles away from the sun every > year and summer is actually further away than fall but... he said "no, > if the orbit was a few inches off" and i didn't want to start a huge > debate which would make me look like him but... I know that a tiny > deviation like 6 inches in orbit must happen all the time... such as > earthquakes and considering the mass of the moon, its orbit must move > the earth a few miles every month so... how much deviation from orbit > would it take for something catastrophic like a huge flood? Aphelion 152,097,701 km (1.016 710 333 5 AU) Perihelion 147,098,074 km (0.983 289 891 2 AU) ============== difference 4,999,627 km (1.96835709 × 10^11 inches) We don't know how close or far would upset the Earth system, but as you know it handles a percent or two quite easily.
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Date: 21 Aug 2006 11:06:54
From: oriel36
Subject: Re: Two Questions...
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This should be familiar to you - "Gerald Kelleher (aka oriel36) is a celestial mechanics nut who thinks that astronomy should have stopped with Kepler, and never gone on to the analytical universe of forces and accelerations put forth by Newton." http://astro.isi.edu/reference/faq.html If you are going to make a pathetic attempt to be technical then be sure to get it right.I do not mind you subhuman grasp of astronomical matters or what amounts to the same thing - your adherence to celestial sphere geometry,I do mind that you cannot even compete with Newton. Astronomy stopped at Roemer,after that Newton bundled the Keplerian insight on orbital geometry with Roemerian insight on finite light speed for his silly terrestial ballistics agenda - "For to the earth planetary motions appear sometimes direct, sometimes stationary, nay, and sometimes retrograde. But from the sun they are always seen direct, and to proceed with a motion nearly uniform, that is to say, a little swifter in the perihelion and a little slower in the aphelion distances, so as to maintain an equality in the description of the areas. This a noted proposition among astronomers, and particularly demonstrable in Jupiter, from the eclipses of his satellites; by the help of which eclipses, as we have said, the heliocentric longitudes of that planet, and its distances from the sun, are determined." Newton Do you know what the above paragraph means as an accurate description of Ptolemaic,Copernican,Keplerian and Roemerian reasoning ?, it means absolutely nothing,it is junk and particularly that festering sore of a first sentence. I could not care less if you put my name on your site or not but if you do so and try to squeek out a technical statement then be sure to get it right. Brian Tung wrote: > > 1. When a teacher at school was talking about how perfect the placing > > of earth was, the nerdy guy in the class said "ya, if it were a few > > inches closer to the sun, the glaciers would melt and destroy the > > earth, and if it were a few inches away, then we would freeze to death" > > I, actually knowing more and not usually showing it, pointed out that > > the earth alternated from ~90-96 million miles away from the sun every > > year and summer is actually further away than fall but... he said "no, > > if the orbit was a few inches off" and i didn't want to start a huge > > debate which would make me look like him but... I know that a tiny > > deviation like 6 inches in orbit must happen all the time... such as > > earthquakes and considering the mass of the moon, its orbit must move > > the earth a few miles every month so... how much deviation from orbit > > would it take for something catastrophic like a huge flood? > > It would depend on how quickly the shift happened, but of course, six > inches would not make any kind of difference at all. > > As you noted, the Earth's distance from the Sun varies by a few million > miles throughout the year, so at least that deviation, at that rate of > change, is noticeable, but hardly catastrophic. Some studies suggest > that the Earth could have formed within a fairly wide range of distances > from the Sun (typically from 0.9 AU to 1.4 AU) and still have permitted > liquid water, which is required for the kind of life we're familiar > with. > > That doesn't mean, though, that the Earth's orbit could vary that much > *in a single year* and still support life. The Earth evidently has some > systems that act as a kind of buffer--systems such as the greenhouse > gases in the atmosphere (naturally as well as artificially). > > If the Earth were further from the Sun, there is some feedback that > would liberate extra greenhouse gases and keep the planet warmer than it > would have been otherwise; if it were closer, some of the greenhouse > gases would go back into solution. Some of this is indicated by the fact > that life that depends on liquid water existed at a time when we know > the Sun to have been much cooler than it is today. Much more greenhouse > gas content was needed in order to sustain that life, and it must have > gradually been absorbed by rocks or ocean water as the Sun got warmer. > > There's a limit, of course; you can't remove more greenhouse gases from > the atmosphere than there are to begin with. As the Sun continues to > warm, greenhouse gases will continue to depart the atmosphere in order > to maintain a reasonably comfortable equilibrium, but once they're all > gone, the increasing heat of the Sun will continue undeflected. It is > expected that within a billion years, our oceans will have completely > evaporated. Fortunately, a billion years is a very long time; we have > no reason to believe that human beings will still be around in any > event. The same kind of reasoning leads us to suggest that the Earth > couldn't be too much closer (about 0.9 AU) without overheating. > > All these systems work as well as they do, however, because the changes > are relatively slow. They operate on geological time scales. They > couldn't work on time scales of a few months, which they would have to > if the Earth swung from between 0.9 AU to 1.4 AU within a single year! > It is even unclear whether the climate on the Earth can be held equable > when human influences are added in; these effects appear to operate on > the scale of several decades. We'll see. > > > 2. I have been interested in astronomy lately and I wondered what are > > the price ranges for telescopes? And are there any that you can sync > > with your computer and see digital images/ type in long. and lat. and > > it shows that part of the sky? > > If you only want to observe visually, and don't need to involve a > computer/camera in the mix, they can be pretty inexpensive--maybe $200 > U.S. will get you a decent six-inch telescope on a simple Dobsonian > mount. It's the steadiness and sky-following ability needed for > magnified photography and imaging that requires the mount to be > exceptionally stable and drives the price up. Computerizing the scope > so that it goes where you ask it to is relatively inexpensive, with > anywhere from one to a few hundred dollars being added to the price, > depending on how sophisticated the system is. By comparison, a steady > mount capable of doing single-shot long exposure imaging may be a > couple of thousand dollars on its own. > > But yes, they're all available. One place to start is Orion: > > http://www.telescope.com/ > > Their prices tend to be just a tad higher than competitors, but their > customer service is highly reputed. > > -- > Brian Tung <brian@isi.edu> > The Astronomy Corner at http://astro.isi.edu/ > Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/ > The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/ > My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
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Date: 21 Aug 2006 10:40:19
From: Brian Tung
Subject: Re: Two Questions...
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> 1. When a teacher at school was talking about how perfect the placing > of earth was, the nerdy guy in the class said "ya, if it were a few > inches closer to the sun, the glaciers would melt and destroy the > earth, and if it were a few inches away, then we would freeze to death" > I, actually knowing more and not usually showing it, pointed out that > the earth alternated from ~90-96 million miles away from the sun every > year and summer is actually further away than fall but... he said "no, > if the orbit was a few inches off" and i didn't want to start a huge > debate which would make me look like him but... I know that a tiny > deviation like 6 inches in orbit must happen all the time... such as > earthquakes and considering the mass of the moon, its orbit must move > the earth a few miles every month so... how much deviation from orbit > would it take for something catastrophic like a huge flood? It would depend on how quickly the shift happened, but of course, six inches would not make any kind of difference at all. As you noted, the Earth's distance from the Sun varies by a few million miles throughout the year, so at least that deviation, at that rate of change, is noticeable, but hardly catastrophic. Some studies suggest that the Earth could have formed within a fairly wide range of distances from the Sun (typically from 0.9 AU to 1.4 AU) and still have permitted liquid water, which is required for the kind of life we're familiar with. That doesn't mean, though, that the Earth's orbit could vary that much *in a single year* and still support life. The Earth evidently has some systems that act as a kind of buffer--systems such as the greenhouse gases in the atmosphere (naturally as well as artificially). If the Earth were further from the Sun, there is some feedback that would liberate extra greenhouse gases and keep the planet warmer than it would have been otherwise; if it were closer, some of the greenhouse gases would go back into solution. Some of this is indicated by the fact that life that depends on liquid water existed at a time when we know the Sun to have been much cooler than it is today. Much more greenhouse gas content was needed in order to sustain that life, and it must have gradually been absorbed by rocks or ocean water as the Sun got warmer. There's a limit, of course; you can't remove more greenhouse gases from the atmosphere than there are to begin with. As the Sun continues to warm, greenhouse gases will continue to depart the atmosphere in order to maintain a reasonably comfortable equilibrium, but once they're all gone, the increasing heat of the Sun will continue undeflected. It is expected that within a billion years, our oceans will have completely evaporated. Fortunately, a billion years is a very long time; we have no reason to believe that human beings will still be around in any event. The same kind of reasoning leads us to suggest that the Earth couldn't be too much closer (about 0.9 AU) without overheating. All these systems work as well as they do, however, because the changes are relatively slow. They operate on geological time scales. They couldn't work on time scales of a few months, which they would have to if the Earth swung from between 0.9 AU to 1.4 AU within a single year! It is even unclear whether the climate on the Earth can be held equable when human influences are added in; these effects appear to operate on the scale of several decades. We'll see. > 2. I have been interested in astronomy lately and I wondered what are > the price ranges for telescopes? And are there any that you can sync > with your computer and see digital images/ type in long. and lat. and > it shows that part of the sky? If you only want to observe visually, and don't need to involve a computer/camera in the mix, they can be pretty inexpensive--maybe $200 U.S. will get you a decent six-inch telescope on a simple Dobsonian mount. It's the steadiness and sky-following ability needed for magnified photography and imaging that requires the mount to be exceptionally stable and drives the price up. Computerizing the scope so that it goes where you ask it to is relatively inexpensive, with anywhere from one to a few hundred dollars being added to the price, depending on how sophisticated the system is. By comparison, a steady mount capable of doing single-shot long exposure imaging may be a couple of thousand dollars on its own. But yes, they're all available. One place to start is Orion: http://www.telescope.com/ Their prices tend to be just a tad higher than competitors, but their customer service is highly reputed. -- Brian Tung <brian@isi.edu > The Astronomy Corner at http://astro.isi.edu/ Unofficial C5+ Home Page at http://astro.isi.edu/c5plus/ The PleiadAtlas Home Page at http://astro.isi.edu/pleiadatlas/ My Own Personal FAQ (SAA) at http://astro.isi.edu/reference/faq.html
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Date: 21 Aug 2006 17:25:52
From: Craig M. Bobchin
Subject: Re: Two Questions...
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Item 1: Google planetary habital zone (HZ) and you will find a wealth of information on it. It is estimated based on the Earth/Sol system that the HZ is between .95 - 1.15 AUs in size. That is quite a range of distance (~88,330,000 - 106,000,000 miles) so deviations would have to be in millions of miles to be noticeable. Item 2: Price ranges for good telescopes are ~$300.00 for a 6" dobsonian on up. The more computerization you add the higher the prices go, and most of the cost is in the computer not the optics. So you would get less apature for the same money. What do you mean see digital images? You look through a scope, (unless you are taking images) if you want to see digital images go to the web. Now there are scopes that you can hook up to a PC/laptop and use the computer to move the scope to diff. objects. But most of those come with a built in computer that you use to select what you want to view. You don't type in Lat/Long. That is just to set your observing site. You can however enter RA and Dec coordinates and slew that way. In article <1156032380.292747.114700@75g2000cwc.googlegroups.com >, wiiwiillwiin@gmail.com says... > Ok, These two questions are totally unrelated but I didn't want to take > up two topics so...: > > 1. When a teacher at school was talking about how perfect the placing > of earth was, the nerdy guy in the class said "ya, if it were a few > inches closer to the sun, the glaciers would melt and destroy the > earth, and if it were a few inches away, then we would freeze to death" > I, actually knowing more and not usually showing it, pointed out that > the earth alternated from ~90-96 million miles away from the sun every > year and summer is actually further away than fall but... he said "no, > if the orbit was a few inches off" and i didn't want to start a huge > debate which would make me look like him but... I know that a tiny > deviation like 6 inches in orbit must happen all the time... such as > earthquakes and considering the mass of the moon, its orbit must move > the earth a few miles every month so... how much deviation from orbit > would it take for something catastrophic like a huge flood? > > 2. I have been interested in astronomy lately and I wondered what are > the price ranges for telescopes? And are there any that you can sync > with your computer and see digital images/ type in long. and lat. and > it shows that part of the sky? > > Thank you ;-D > >
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