Windows on the Universe: Refracting Telescopes

The telescope is an optical instrument designed to make distant objects appear nearer. It contains an arrangement of lenses or mirrors or both that gathers visible light, permitting direct observation or photographic recording of distant objects. (Lacki, B. C. 2011). With the use of telescopes we have been able to learn a lot more about the planets in our universe. It has helped us understand about some of the history of everything around us. Also it has been able to track asteroids and comets or any randomly flying objet in outer space that might become threatening to our planet.

surface of a glass. With concave mirrors, the reflection would appear to be out in front of a

FIGURE 1.7- A magnified view of a single lenslet shows a portion of an aberrated wavefront (red curve) passing through. If the wavefront had been flat (aberration-free), it would have focused to a point on the video sensor (CCD) on the lenslet's optic axis (yellow dot). Refractive errors distort the wavefront out of a plane, so a wavefront portion (red curve) enters the lenslet curved and tilted. The light will therefore be focused to another part (red dot). The dot will be shifted by an amount that is in direct proportion to the wavefront tilt.

Meridian has been manufacturing fine telescopes for 80 years and has developed a well-earned reputation for quality craftsmanship. The company itself produces and sells two distinct lines of telescopes, which are produced in its 200,000 square feet facility. Furthermore, both lines have been developed to appeal to distinct target audiences who have an interest in the company’s products. The older line, for which there has been steady demand, consists of small professional telescopes that ultimately have laid the foundation for Meridian’s strong reputation. Following the success of

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6.  A common problem with refracting telescopes is a fringe of false color around the image, caused by the inability of a large lens to refract all colors of the spectrum to a common focus. This is known as ______.

A convex lens (with an index of refraction greater than the surrounding medium) causes the light from a given source on one side of the lens and passing through the lens to converge on the other side of the lens, forming an image at the focus. A concave lens with the same properties would cause that light to diverge, or spread out.

It makes use of Index Matched Lenses. They are lead free and the edges are blackened. This gives you a very bright, vivid clarity, which will be noticed immediately after you hold the scope up to your eye.

WHY, THERE IS EVEN A PAIR OF SPECTACLES WITH A MYRIAD OF ADVANCED LENSES THAT WORKS AS BOTH A SIGHT ENHANCING DEVICE AND MORE! WITH EACH LENS THAT IS SLID INTO PLACE JUST ABOVE THE FIRST RING OF GLASS, MORE AND MORE IS ABLE TO BE SEEN.. UNTIL THE STARS COME INTO VIEW. IT IS STILL AN ADVANCING PROJECT, AS IT IS NOT AS POWERFUL AS A TELESCOPE ITSELF, BUT WHO KNOWS WHEN THE BOUNDARY WILL BE BROKEN AND A SCIENTIFIC DISCOVERY WILL BE MADE TO PERFECT THIS GADGET.

By looking at the different wavelengths or the spectrum of light from a celestial object, you can tell many of its properties and features. To do this, the Hubble Telescope is equipped with various scientific instruments. Each instrument used

As proposed in an article posted on amazing space.org, “The telescope, a basic reflector with a 94.5 in (2.4 meters) mirror.” While also having being a second mirror that the light bounces to to. Within that mirror, many instruments were compacted together that allowed for clear and visible views in infrared and ultraviolet light. It was different compared to any other ground based telescope whereas it allowed astronomers to observe and witness details that had never been seen before due to Earth being in the way for those other telescopes. The telescope revolves around the earth completely every ninety-seven minutes at the speed of five miles per second, allowing for many observations in space. The observations occur when light hits the main mirror and then bounces towards the second mirror in which the second one focuses the light. The telescope began to be created in 1977 and was originally supposed to launch during the year of 1985. Unfortunately an accident had occurred when a space shuttle challenger exploded and flights into space took a halt. It was finally launched on April 4th of 1990 once the halt had stopped. The improved observations had begun and the history of astronomy had changed. Unfortunately there were some minor setbacks that had to be dealt with. One setback was that the primary mirror was ground incorrectly in which the curve of it was too flat. It was off just

Optical astronomers have the sun to deal with. Because our sun is closer to us than other stars, a greater amount of light reaches us. When the sun is out, it effectively blocks visible light waves emitted by a distant star from reaching us. At night there is no interference. Radio Astronomers have the advantage in that they are able to observe at any time of the day. Since the sun does not produce radio waves, there is no interference received by the telescope from the sun.

Catadioptric telescopes are those that use both mirrors and lenses to produce an image. The most common or popular type of catadioptric telescope is the Schmidt-Cassegrain telescope. Schmidt-Cassegrain telescopes (SCT) are a catadioptric design, meaning they use both lenses and mirrors. SCTs are primarily reflecting telescopes, but they use a corrector lens to eliminate aberrations that would result from the mirror design alone. In an SCT the incoming light passes through the Schmidt corrector lens (also called a corrector plate) at the front of telescope. It is reflected from a concave primary mirror at the back of the scope which focuses the light to the front of the telescope where it is reflected again by a smaller, convex secondary mirror. Finally, the light travels back through a hole in the primary mirror to the rear of the scope where an eyepiece is located for visual observing. (Starizona.com, 2015)

Resolution is related to the numerical aperture of the objective lens – the higher the numerical aperture, the better the resolution; and the wavelength of light passing through the lens – the shorter the wavelength, the better the resolution.

The light enters through the objective lense and meets at a focal point. That is then magnified through an eyepiece where we see the image. The effects of light passing through lenses are different depending on which lense it is passed through. Double convex lenses works by refracting light rays that are travelling parallel to the principal axis towards the normal surface. When it hits the boundary the light is passing to a more dense medium which is usually glass or plastic. Since the light rays are passing from a medium that it travels fast in to a medium that they travel slow in, it will bend towards the normal line. Which is shown on this diagram. An image is formed in a refracting telescope because the first lense (objective lense) is convex and when the light travels through the lense because the surface is transparent the light travels through the lense and meets a focal point on the other side to create an image that is real, magnified(compared to when viewing with the naked eye) and inverted because the image is formed by real rays that refract and go through the lense instead of reflecting like a mirror. For example if an astronomer is looking at the moon through a refractor telescope the image he will see is real but smaller. The eyepiece lense is also inverted (convex) because this allows the image to be ‘inverted’ again so it is the right way up for our eyes to see. This formula lets us find the distance of image1/f=1/do+1/di. An example of using this formula is if a 4 cm object is placed 12 cm in front with a focal length of 8cm. 1/f=1/do+1/di, ⅛=1/12+1/di, ⅛-1/12 =1/di, 1/24=1/di, di = 24 this equation allows us to find the distance of