how does hubble space telescope steer itself?
99926
In some cases, it uses small manuvering thrusters to steer it, but mostly uses it gyroscopes to steer in and keep it 'locked' on to the portion of the sky it is studying.
840206
It points straight down (if it is mounted so that it can do this) at the magnetic pole. The magnetic and geogrpahical poles do not coincide.
220640
A theodolite measures horizontal and vertical angles. It consists of a mounted telescope that rotates 360 degrees, and can be moved up and down. Inside there are a couple of circular plates marked off in degrees, minutes and seconds.\n\nThe theodolite is fixed to the top of a tripod (just like a camera tripod). By aiming the telescope at an object, the surveyor can 'read' the circle to determine the horizontal angle and the angle above or below the horizon - the vertical angle.\n\nBy combining these angular readings with measured distances, the coordinates of the objects we are measuring can be calculated using the mathematics of trigonometry.
941839
Make sure you don't have a lens cap blocking the other end.  Try aiming at distant objects, not close ones.  It may be that it is focussed for eyes that have a different tolerance than yours, so trying working the focus knob.  Failing to accomplish anything, I suggest you contact the nearest planetarium or science center and ask for help.  If they can't help, they should know members of a local astronomy club who can.
464463
Just set your reference point by yourself. Everywhere can be North in space.
709800
As they said, they use gravity to "slingshot" around the greatest gravity well there is nearby, the sun.  The Voyager probe had to slingshot around the sun to be able to get speeds great enough to leave the Solar System.  Also, by slinging around the sun, we have been able to reach Jupiter and Mars, and further on out.  So, humans have taken lessons from comets on this matter!
719477
I would have to say yes. As an avid amateur astronomer the search for knowledge is always a good thing. After all, the Hubble still has a few good years left in it, but they won't upgrade it (I think it's a mirror, that was made specifically for it, and it's still sitting on earth because NASA wants to scrap the Hubble). Mind you, I could be wrong about NASA's decision, since I heard it was going to change and they would be upgrading after all. As for us willing to spend the money, sure. After all, our tax dollars are being wasted elsewhere. I honestly believe the individual should decide where the majority of their own tax dollars are spent.
54730
Not clear what you mean?  How does it stay up in space? It does that because it is going very fast, which would take it away from earth, but gravity is pulling it back, causing it to curve, and go around the earth, just like a string on a yo-yo if you just whip it around your head. \n\nIf you mean, what does it do, there are different kinds, but most of them get power from solar panels, and have radio receivers and transmitters to communicate back to earth.
1022265
There is no sideways in space, either.\n\nDirections are relative to perspective. The direction that is down to me is the same direction as up is to people on the other side of this round world.\n\nMaybe the earth is inside-out?
901312
b) is the correct answer, as others have said. You know, telescopes are a lot easier to understand if you look at a diagram.\n\nYou can find some here: http://en.wikipedia.org/wiki/Reflector_telescope
209338
Space telescopes are not prone neither to difraction due to the atmosphere; besides, the air flow in the atmosphere introduces distorsion in the light path. \nThese two things (distortion and loss of light power) limit the effective seeing capability of a telescope.\nOne solution has been space telescopes, just like the Hubble. But another solution has been to construct "virtual" large diameter telescopes: they set an array of smaller telescopes which are far apart from each other (the array spans a few kilometers). Then, first, the total amount of light collected is equal to the sum of the light collected in each telescope. The distortion gets "compensated" among the several telescopes.\nAs far as I know, one such telescope, already operational, is being constructed in Chile. The location was selected for being the dryest on earth.
62786
made using easy-to-find materials. The components of this telescope are: \n\n\nring to secure the eyepiece lens from behind \nring for centering the eyepiece lens \neyepiece: lens with focal length of 20-50 mm. You can buy one in an optical or photographic shop, or you can get one free by using the lens of a disposable camera. \nring to secure the eyepiece lens from the front \na cardboard tube for the eyepiece. You can use the tube from a roll of plastic food wrap or paper towels. You can also use short sections of this tube to make rings 1, 2, and 4 which you need to hold the eyepiece lens in place \ncoupling between the eyepiece tube and the main tube. This is a hollow cylinder with an outer diameter that fits snugly into the end of the main tube and an inner diameter that provides a snug but movable fit to the outside of the eyepiece tube. You can make the coupling using several plywood disks glued together or using a polystyrene cylinder with a hole bored through it. If you use polystyrene, you will need to add an opaque covering at each end. \nmain tube. Use a cardboard or plastic tube about as long as the focal length of the objective lens and with an outside diameter of 50-60 mm about. Suitable sources include map mailing tubes and core tubes for carpets, drawing paper, or wrapping paper. \nobjective lens. You can use a common eyeglass lens with a focal length of 500-1000 mm. You can buy it in a optical shop. Ask the optician to reduce the lens diameter in order to fit it precisely into the tube cap \ndiaphragm. Cut it from a black card, then open a hole of about 15 mm in diameter in the center of the disk \nCap of the tube. If you buy a tube for drawing sheets, you should have a cap which will be useful for retaining the objective and the diaphragm. Otherwise, you can made it with a disk of cardboard. Make a series of radial cuts around the edge of the disk to make a set of tabs, Moisten the tabs; then place the tube cap on one end of the principal tube and bend the tabs around the outside of the tube. Glue the tabs together where they overlap, but be careful not to glue the cap to the principal tube yet. When the glue is dry, slip the cap off and cut in the cap a hole a few mm less in diameter than the outside diameter of principal tube. \nThe distance between objective and eyepiece lenses must be equal to the sum of their focal lengths. The eyepiece tube must stick out a few centimeters so you can move it to focus the telescope. Make the length of the principal tube short enough to allow you to grip the protruding part of the eyepiece tube with your fingers as you adjust the focus.\nThe eyepiece tube must slide smoothly in its channel, but it should not be loose enough to fall out if you hold the telescope vertically. Paint the inside of the tubes with black opaque paint (matte finish) or India ink . Secure the cap of the main tube to keep it from pulling away from the tube.
204509
Yes, through wormhole and warp drive. A wormhole should be able to connect distant locations in the universe by bending spacetime, allowing travel between them that is faster than it would take light to make the journey through normal space. \n\nA warp drive would be a mechanism for warping space-time in such a way that an object could move faster than light.\n\nIf you would like to learn more about wormhole, follow this link http://en.wikipedia.org/wiki/Wormhole
790489
Make sure the lens cover is off the tube of the telescope and nothing is blocking the eyepiece.  Once that's done, you're probably just WAY out of focus.  There should be a focusing knob near the eyepiece.  Start turning it in one direction - it might take a while before an image appears.  If it doesn't work after about a minute, start going back in the other direction.  This might be easier to do at night - if you point the out-of-focus telescope at a star, you should see a big fuzzy donut where the star should be (and a few lines through it if you have a reflector).  Once that big donut is reduced to a point source, you're in focus.
153023
hubbel space telescope
988242
well, its not exactly round, its spherical. but yeah, since you can only see it from one side at a time, if you saw it from space it would appear round. kinda like how the sun appears to us. it looks like its moving, but its not, WE ARE. lol.
874946
Hi. This is how NASA does it : http://science.nasa.gov/headlines/y2000/ast02nov_1.htm