The Telescope

by Pavitthra Pandurangan

What is the telescope?

An object used to make distant objects appear closer using a series of curved mirrors or lenses.

• 2,000 years ago - evidence of lenses.• 1608 - Hans Lippershey invents the first

refracting telescope.• 1609 - Galileo invents an improved model.• 1670 - Isaac Newton invents the modern

reflecting telescope.

A Basic Overview

• 1470: Born in Wesel, in western Germany

o A German - Dutch lens-maker• 1508: Filed for patent for his telescope, but

was denied.o Magnification was three times.o Compensated by Dutch government for

providing binocular telescopes.

Hans Lippershey

• February 15, 1564: Born in Pisa, Italy.o Italian physicist and astronomer.

• 1592: Taught mathematics at University of Padua.o Studied Ptolemy.o Convince that Nicolaus Copernicus' theory

(planets revolve around the sun) is correct.• 1609: Heard about the telescope. Learned

more about it, and created an improved model by himself.o Thought of pointing this invention to the skies,

rather than using it in war. o “The Father of Modern Astronomy”

Galileo Galilei

What he saw:

Mountains and craters on the moon. Moons of Jupiter (four largest). Milky Way is a collection of stars. Dark spots on the surface of the Sun.

Published discoveries in March 1610 in The Starry Messenger.

Galileo’s Findings

Known as the refracting telescope. Magnification of twenty times. Parts:

Objective Lens – collects light from a distant object and focuses it into one point.

Small Lens – the eyepiece, brings image to your eye.

This version is not used in modern day astronomy because the lenses are too expensive to reproduce.

Galileo’s Telescope

Convex lens collects and bends light to a focus point.

A concave lens magnifies the image.

Galileo’s Telescope

January 4, 1643: Born in Woolsthorpe. 1661: Attended Cambridge University.

Read about optics and light. Investigated the refraction of light.

1688: Developed the reflecting telescope

Isaac Newton

Idea was from Scottish mathematician James

Gregory, who came up with the design in 1663.

Used two mirrors instead of glass lenses. Primary Mirror: Curved, metal mirror Secondary Mirror: Small, flat mirror

Less chromatic aberration (fringes of color against the boundaries between light and dark) since wavelengths focus at one point.

Helpful for viewing dark objects.

Newtonian Reflector

A large, concave mirror collects and reflects the incoming light. Then a flat mirror focuses the light and reflects it to the eye piece. The eye piece then magnifies the image.

Newtonian Reflector

• Scientists accepted that the Earth was not the center of

the galaxy. • The Sun and Moon aren’t perfect cellestial objects.• Examine stars, planets, galaxies, space, etc.• Look at our universe in different wavelengths (gamma,

infrared, radio).• See beyond what we can now, and understand the

universe.• Creation of famous telescopes like the Keck Telescope,

the Kitt Peak Observatory, and the Hubble Space Telescope.

Impact

"Galilei, Galileo." World Book's Biographical Encyclopedia of Scientists. Vol. 3. Illinois: World Book, 2006. 117-

19. Print. ^“Rigden, John S.” Macmillan Encyclopedia of Physics. Vol. 2. New York: Simon & Schuster Macmillan, 1996.

647-49. Print. Strano, Giorgio. "Galileo’S Telescope: History, Scientific Analysis, And Replicated Observations."

Experimental Astronomy25.1-3 (2009): 17-31. Academic Search Premier. Web. 27 Nov. 2012. "Galileo." (n.d.): Funk & Wagnalls New World Encyclopedia. Web. 27 Nov. 2012. Shubinski, Raymond. "How The Telescope Remade The Universe. (Cover Story)." Astronomy 37.5

(2009): 30.MasterFILE Premier. Web. 27 Nov. 2012.

http://www.biography.com/people/galileo-9305220 http://csep10.phys.utk.edu/astr162/lect/light/refracting.html http://www.history-of-the-microscope.org/hans-lippershey-invented-the-telescope.php http://www.robinsonlibrary.com/science/astronomy/instruments/lippershey.htm http://www.egglescliffe.org.uk/physics/astronomy/telescope/newtontele.html http://www.newton.ac.uk/newtlife.html https://www.google.com/#hl=en&sugexp=les

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Sources