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We now offer the Cool It! card game in our Science Store. Cool It! is the new card game from UCS that teaches kids about the choices we have when it comes to climate change.
Art and science combine to show an ancient view of the Sun and Earth. Look closely to see the Sun in the center. Four images of Earth surround the Sun. Each Earth represents the different seasons, spring, summer, autumn and winter. Original art by Andreas Cellarius (1596-1665).
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(c)1995 Visual Language, All Rights Reserved

The Changing Night Sky

If you look at the night sky different times of the year you see different constellations. This change is due to the motion of the Earth in its orbit around the Sun. Each day a few stars are visible in the east that were not visible the night before. If you were to measure how much the sky "shifted" from one day to the next you would discover that it "shifts" approximately one degree per day. This should not be surprising because, if you think about it there are 365 days per year and 360 degrees in a circle. Anyway, the sky doesn't shift, it is another case of apparent motion. The "shift" of the sky is really the motion of the earth around the sun.

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The Fall 2009 issue of The Earth Scientist, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store.

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Science, Evolution, and Creationism

How did life evolve on Earth? The answer to this question can help us understand our past and prepare for our future. Although evolution provides credible and reliable answers, polls show that many people turn away from science, seeking other explanations with which they are more comfortable....more

Andromeda

Andromeda is a "V" shaped constellation best viewed in the fall if you live in the Northern Hemisphere. Andromeda lies close to the north pole, so only a few in the Southern Hemisphere can see this strangely...more

Aquarius

Aquarius is a member of the Zodiac, a group of constellations that the Sun travels through each year. It is best viewed in the fall in the southern sky, although much of the northern hemisphere can see...more

Cancer

Cancer, the Crab, is a member of the Zodiac, a group of constellations that the Sun travels through each year. Cancer is best seen during the month of March, but is visible from December through June....more

Canis Major

Canis Major is known as the Great Dog. In Greek myth, it is said that this constellation, along with Canis Minor, are Orion's hunting dogs. Canis Major was one of the most important constellations in...more

Capricornus

The constellation Capricornus represents the figure of either a goat or a sea-goat in the sky. Capricornus is also a member of the Zodiac, a special group of constellations that the Sun travels through...more

Cetus

The constellation Cetus represents the Sea Monster. It is one of the largest constellations known. In classical civilizations, the figure was the giant sea monster that almost ate Andromeda. King Cepheus...more

The Unchanging Sky

The unvarying aspect of the relationships of the stars' positions may have suggested to the ancients something that was analogous to their beliefs about the universe. It is not surprising that they chose...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF