Definition Telescopes – are instruments used to observe remote, distant objects. It collects and focuses light coming from the observed object, resulting to a clearer, magnified image of it.* We need magnification for our eyes don’t have enough space to see distant things. Pixel example.
A Bit of History• Coming from the word “tele” – far and “skopein” – As of now, far seeing. from the simple• Since its invention in 1608 by Hans Lippershy, it lens ancestor, it has has been widely used in Astrophysics. Galileo was evolved into considered the father of telescopes. gamma ray,• Galileo first used a telescope for astronomical infrared telescopes, purposes. basically the types• Kepler improved the design further using two of electromagnetic convex lenses. waves available.
• Properties – Aperture – how well it can collect light. • Larger diameter = more light = clearer view – Magnification• Factors affecting the performance of telescopes in magnifying objects vary depending on the following: – Availability of Light in the Environment – Combination of Lenses/Mirrors Used • Thickness and focal length
Parts of a Telescope• Objective Lens – collects lots of lights and focuses it into avery small image at the focus.•Eyepiece Lens – magnifies the focused image into a size thatperfectly fits into the viewer’s eyes.
Two Basic Types• Reflecting • Refracting – An optical telescope. – Also an optical • Increases apparent telescope. brightness of object, and – Primarily uses lenses. its angular size. – Invented earlier. – Invented in the 17th Century. – More used nowadays in astronomical labs. – Mirror based.
RefractingTelescope• Uses concave objectiveand convex ocular lens.•Bends parallel lightsinto a focal point tocreate a clearer image.•Angular magnification isequal to the ratio ofobjective focal length overeyepiece focal length.•Used in binoculars.
•Pros: •Low Maintenance •Clear and contrasting Images •Ease of Usage•Cons: • Chromatic Aberration • Fringes or Rainbow like appearances at the points of the images where dark and light colors appear. • Because of the different wavelengths in a white light. •Costs more. •Not developed for Astronomical Purposes. • Light loss.
ReflectingTelescope•Commonly uses parabolicprimary mirror and angledflat secondary mirror to focuslight into the eyepiece.• Famous models areGregorian First model built in 1688 by Newton.and Newtonian telescopes.•Easier to manufacture, Its popularity increased with thecheaper materials and less advent in silverspherical abberations. coating, parabolic mirror manufacturing, seg mented mirrors, etc.
•Pros •Cheaper to manufacture •More capable to detect faint astronomical objects. • Tends to have more compact design.•Cons • The tube body can get easily destroyed = high maintenance. • Bulkier Design •Spherical Abberation •Higher magnification = smaller field of view
CatadioptricTelescopes•Uses both lenses andmirrors.•Used widely in takinghighly accuratemagnifications/lighting .I.e.: microscopes,headlamps, etc.
Here are other types of Telescopes Radio Telescopes
Gemini N Mauna Kea (4213 m), HawaiiGemini S Cerro Pachon (2722 m), Chile
William Herschel telescope 4.2 m, La Palma (2400 m), Canary Islands, SpainOptical and IR