can i get a detailed explanation of the physics behind telescopes?
409995
There are two basic kinds, refracting telescopes and refleting telescopes. Refracting telescopes depend on light bending through transparent materials (glass). Have you ever put a pencil in a glass of water? Try it. See how it seems to bend? That's because the light travels at a different (slower) speed through the water, which makes it bend. \n\nA telescope lens is circular, so that all the light rays refract in the same direction, focusing to a point, and the image appears larger (closer.)\n\nThe reflecting telescope works differently. It has a curved mirror to reflect all the light rays to a point. So more light is gathered, across the area of the mirror. You see an image that is larger (closer.)
370841
The telescope has a built-in computer to find and track objects in the sky. There are ports for other Meade modules, but not for hooking the telescope up to another computer, as far as I could tell from a quick read through of the manual. If you don't have the manual: http://www.meade.com/manuals/TelescopeManuals/LXseries/LX90-LNT.pdf#search='LX90%20telescope'\n\nIf you were expecting to see stars on your computer, you did not read much about this telescope before you bought or got it.
524609
What you see depends partially on the kind of telescope, the quality of its optics, the aperture you have, and the particular eyepiece used. For example, with my 10" aperture Dobsonian (Newtonian) telescope, the images are not as good as they are when using my smaller aperture 8" Schmidt-Cassegrain.  Larger is not necessarily better if you're looking for detail.  Also, the eyepiece used determines the magnification largely. If you use a higher numbered eyepiece like 32 mm the image will be smaller and less detailed.  If you use a smaller numbered eyepiece like 10 mm the image will be larger and more detailed.  If you have a refractor with a 60 mm (2.4") aperture, you should be able to see the solar system objects like the planets and the moon quite well.  For more detail when viewing the moon, use a greater magnification eyepiece. The same applies to the planets, but since the planets are farther away, atmospheric distortion can interfere with high power eyepiece viewing because it also magnifies all the imperfections in the atmosphere.  There's a lot more to this than I have mentioned, but basically the eyepiece you use and its compatibility with your telescope determines the amount of detail you see on either the planets or the moon.  You should be able to see lots of detail on the moon with even the smallest telescope, using its highest powered eyepiece (lowest numbered). Also, you can double the magnification of any eyepiece by getting 2X Barlow eyepiece and using it with any eyepiece.  Be sure that you get one that is compatible with your telescope, though.
860328
No,\nI wouldn't say that's entirely impossible but it'd be a small technical challange.\n\nIf you can't afford a telescope you should contact your local astronomical society. Many will let members borrow telescopes for free or they may be able to tell you of a star party where you can go and others will let you look through their telescopes.
823026
Being so far away, telescopes don't have the resolution needed to see the equipment. It's a bit like trying to use Google Earth and figuring out what the make and model of each car is. We can see the area of the moon where they touched down, but the equipment is just too small.\n\nBeing so far away, the light reflected off the metal facets of the hardware will rarely be reflected at just the right angle to be seen. The moon orbits Earth at a 5 degree inclination. Plus, the landers aren't at the moon's equator, which complicates things even more. The equipment will need to be at the right place at the right time, and our telescopes will need to be looking in the right place at the right time, just for a chance flash of something. It's a lot of variables that almost never come together right.
665860
http://www.ehow.com/how_17057_make-simple-telescope.html
336605
Greetings,\n\nWe astronomers study many different aspects of the universe.\n\nThere are radio astronomers who study the radio waves emanating from many different objects in the universe from black holes to listening for ET.\n\nThere are astronomers who specialize in using X-rays to view different objects in the sky, such as the Chandra X-ray observatory.\n\nThere are astronomers such as myself who are amateurs that simply enjoy pointing our telescopes at objects and viewing them.\n\nCheck out the links at the bottom.\n\n-matt
756102
Yes, almost all serious research telescopes are controlled this way.  There are a handful of amateur telescopes which are internet controllable. \n\nbut most require a user name and password, and are for authorized  users only.  The ones that don't are usually very very busy. \n\nYou can see an example of one at \n\nhttp://observatory.space.edu/f4_facilities/f3_internet%20telescope/index.php\n\nand a description of the technology at \n\nhttp://www.atnf.csiro.au/pasa/17_2/mckinnon/
1185030
For most operations, the telescope uses reaction wheels.  These are gyroscopes on motors.  If the telescope wants to pan in one direction, it speeds up a reaction wheel in the opposite direction, and conservation of angular momentum ensures that if the wheel spins faster counter-clockwise, the telescope spins faster clockwise to compensate.  Once the correct angle has been achieved, the reaction wheel is spun back to its normal speed, and the telescope stops panning.  This method is much more precise than rockets which would usually have to burn continuously to hold a stable attitude, polluting the vicinity with burned materials which can interfere with imaging or degrade the mirror by accumulating on it.\n\nOver time, external torques can pull the telescope out of alignment, requiring the reaction wheels to spin faster and faster to keep it steady.  Eventually they reach their maximum rotation rate, and something has to be done.  This is done by "reaction wheel desaturation".  Only at this point do the rockets on the telescope fire up and apply a torque which lets the reaction wheels be spun back down to their normal operating range.  The telescope can't do any science while the rockets are firing.\n\nThe pointing accuracy and stability of the telescope are controlled by locking onto guide stars.  It has specialized instruments that let it control its orientation by measuring the location of known bright stars.
1085025
An optical maser. Now there's an obscure reference. How many know that without looking it up?
32162
C is true. The others don't really make sense.\nThey are also inherently chromatic, more efficient. Even small ones are cheaper for the size than refracting. \nHubble Space Telescope is reflector also it will work with Ultra violet light, and more precisely focuses than glass can.
268357
option 4. coz a telescope helps us see images of gigantic objects, so a diminished image wrt object forms. also, the final image formed is upside down(though it is virtual) coz the ist image formed is real and inverted.\ntrust me, i just gave my phyics board exams.
190587
Refraction bent the light when passing in angle throught glass or other material, it can be use in a optical telescope. But the lens used must become thicker when diameter grow, and that make bigger lens really expensive.\n\nreflection can also be use to build telescope. Big mirror can be build at lower cost than lens.
982426
That depends what consideration you have.  Reflecting have the advantage of having less chromatic aberration than refractor, and tend to be larger for a given weight.  The most important aspect for a telescope is the size of the primary mirror, because it defines the light gathering capability, so this is a case where bigger is better (as long as the quality is there, evidently)\nCassegrain is a variation of the reflector, where a secondary mirror sends the light back through the center of the primary; the other style is Newtonian where a diagonal mirror sends the light t the side.  For moderate size telescope Newtonian is more comfortable.\nA very important aspect to consider is also the mounting.  If you only want to do optical observation, then a Dobsnian mounting is very cheap, as it forgoes the tracking mechanism.  If you would want to do astophotography with long exposure, then you would need an equatorial mount with a drive that can track a star.  Recent models rely on computerized motorization, which as most electronics, have allowed the advanced capabilities for an relatively acceptable price.\nMy suggestion is that you document yourself, perhaps buy a couple of issues of astronomy magazine, like Astronomy or Star & Telescope, and get acquinted with the market.  You will be able to decide what you want, and what you can afford.\nAnd I hope you have access to clear sky and dark night.\nHappy observations!
39097
Check out the sites below for in-depth explanations.  \nThe first one is from NASA.
1090100
This can be answered very, very simply.\n\nRelativity works well in  in it's area of expertise, astronomy and space science.  Basically, the scientists took the answers (how the planets revolve around the Sun, the Mass of the planets and stars, how the stars and galaxies move) and created an elegant series of equations to explain them all.  They believed their equations to be correct because this is what they were observing, so it must be true right?\n\nWell no, as we built better telescopes we began witnessing objects and entire galaxies moving far too fast for their observed mass, defying the equations and defying gravity!  It wasn't light pressure robbing these celestial objects of a few arc seconds, which is what sprung Einstein to whop up Relativity.  Venus was so much of a mystery, but Einstein cracked it, right?\n\nWRONG!  If the atom doesn't fit, you must aquit!  Electromagnetic forces have been known to cause these very same effects we witness the galaxies doing.  If the astronomers can't explain something they see, they blame it on magnetics.  Double-helix galaxies, just like our DNA, are floating around out there.  That should tell you where you should start looking to explain the molecular and Universal connection.\n\nVenus' orbit is nearly a perfect circle, and it spins the other direction very slowly.  It used to be called the hairy planet, the smoky planet, and bearded planet.  It's latin name means morning star.  It was literally glowing!  I'm sure some electromagnetic stuff was going on with it, and that would help explain it's brand spanking new surface.\n\nhttp://answers.yahoo.com/question/index;_ylt=AuzSsKSIJO_WapqWQB7tQcPsy6IX?qid=20060612222952AAFdmeo\n\nMars got blown the hell up.  That's a start on finding out about it right there, google should take you the rest of the way.  Hope this helped you understand why those two theories will never be united.  One of them, relativity, was based on a few wrong assumptions.
1143611
Well, first off avoid the TASCO ones 'cos they have a reputation for using cheap optics with overly powered eyepieces (according to those in the know) - I bought one myself off Ebay a couple of years ago.\nIt ain't exactly bad (apart from the wobbly stand, cheap eyepieces, hopeless spotting scope)...... more stupid but savable than bad. Couple weeks ago I finally got round to buying a better quality "Orion Explorer II 7-21mm Zoom" eyepiece, which is a good investment, but the usual New Telescope/Accessory + sky gone cloudy once it's dark enough outside to use it jinx has been occuring ever since I got the blinkin' thing!\n\nLooking @ Telescopes.com, within your budget I'd suggest...... *drum roll*....... \nthe \nCelestron - FirstScope 114 EQ Short Newtonian Reflector  @ $159 (knocked down from $377)  http://www.telescopes.com/products/Celestron_FirstScope_114_EQ_Short_Newtonian_Reflector_5936.html\nor the Meade - 114EQ-A Short Tube EQ Reflector @ $179.95 (knocked down from $249)  http://www.telescopes.com/products/Meade_114EQ-A_Short_Tube_EQ_Reflector_-_Deluxe_Mount_42684.html\n\nAnother alternative is to scour the adverts in the back of Astronomy magazines for ones people are selling off..... or of course good old Ebay\n http://photography.listings.ebay.com/Binoculars-Telescopes_Telescopes_W0QQfromZR4QQsacatZ74927QQsocmdZListingItemList\n\nFor more advice, check out:\nhttp://skyandtelescope.com/howto/scopes/