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Our Glaciers: Then and Now activity kit helps you see the changes taking place in glaciers around the world. See all our activity kits and classroom activities.

Sun Reference Data

Diameter: 1.4 million km
(870,000 miles)

Age: 4.5 billion years
Mass: 330,000 x Earth Distance from Earth: 149.6 million km (93 million miles)
Density: 1.41 (water=1) Distance to Nearest Star: 4.3 light years
Solar Wind Speed: 3 million km/hr. Luminosity: 390 billion billion megawatts
Solar Cycle: 8 - 11 years Temperature at surface: 5,500o C (9,932o F)
Temperature at Core: 14 milliono C (22.5 milliono F) Temperature of Sunspots: 4,000o C (7,232o F)
Rotation Period at Equator: 25 Earth days Rotation Period at Poles: 35 Earth days

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Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA