Have you ever looked through a telescope at the night sky? Stars, moons, and planets become even more brilliant and distinct. Glancing up at the sky with our own eyes, we see only the tiniest fraction of the light that blazes from other stars and galaxies. Telescopes help us to focus that light and allow us to see more than we ever imagined was out there.

The first optical telescope was invented in the 1570's and consisted of one concave lens and one convex lens fitted inside a tube. The lenses refracted light and magnified objects two to four times. By 1609, the astronomer Galileo had developed a better model of the refracting telescope that magnified by about 20 times. With this instrument he saw that the moon, which many people thought was perfectly smooth, was actually covered with craters, peaks, and valleys! He also dicovered four of Jupiter's moons. Astronomy would never be the same.

The magnification of refracting telescopes could only be increased by lengthening the tube that contained the lenses. Thus, the father into space people wanted to see, the longer the telescope had to be. In 1671, Sir Isaac Newton invented a reflecting telescope, a vast improvement over the refracting model. Reflecting telescopes contain a parabolic mirror that reflects all the light that hits it back through a single point, the focal point. From the focal point, the concentrated light travels up the tube to a flat mirror that deflects it into the eyepiece. The length of the tube can be considerably shorter than that of a refracting telescope.

This reflecting technology has been incorporated into amazing machines like the Hubble Space Telescope. Hubble orbits the Earth on a satellite, and the view it gives us is undistorted by the Earth's atmosphere. The telescope weighs 12 tons, and its parabolic mirror is eight feet in diameter. Hubble has given us pictures of comets, galaxies, black holes, and of the birth of stars. Yet our wonder at these sights could not surpass the wonder Galileo must have felt when he looked through his own small telescope at the moon for the first time in human history.

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Thanksgiving is just around the corner! It's (Thursday) November 26, this year. Use videos, lessons, and worksheets to teach the history and cultural significance of the holiday. Then, enjoy our crafts to celebrate and decorate!

December Calendar of Events
December is full of events that you can incorporate into your standard curriculum. Our Educators' Calendar outlines activities for each event, including: World AIDS Day (12/1), International Volunteer Day (12/6), Hanukkah (begins at sundown 12/6), Handwashing Awareness Week (12/6-12), Computer Science Education Week (12/7-13), Human Rights Day (12/10), Winter Solstice (12/22), Christmas (12/25), Kwanzaa (begins 12/26), Visit the Zoo Day (12/27), and New Year's Eve (12/31). Plus, celebrate Bingo's Birthday Month, Universal Human Rights Month, and Write to a Friend Month all December long!

Hour of Code
Introduce your students to basic coding and computer science! Celebrate Computer Science Education Week from December 7-13, 2015 with our Top 5 Free Coding Tools for Kids, Top 5 Free Coding Tools for Teens, or the Hour of Code resources provided by Code.org®

Interested in using different types of media in your classroom? We have a growing collection of videos, with related activities, for holidays and events, including: slavery & the Civil War, American History, U.S. Presidents, handwashing awareness, the Common Core, women's history, Memorial Day, the American Revolution, and the environment. Enjoy!

Teaching with Comics: Galactic Hot Dogs
Reach reluctant readers and English-language learners with comics! Our original teaching guides to the Galactic Hot Dogs comic series (chapters 1-4 and 5-8), as found on Funbrain.com (and now in print!), will take students on a cosmic adventure while engaging their creative minds. Plus, find even more activities for teaching with comics, featuring many other classic stories.