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This hands-on science video explains Einstein’s light-bending concept using nothing more than a wine glass and an LED light representing a star. In this video, Exploratorium Senior Scientist Paul Doherty explains why you rarely see a true scale model of the Earth, sun, and moon. Understanding the true scale of the solar system helps us appreciate the rarity of total solar eclipses: it’s unusual when objects at such distances line up perfectly. Únete a la astrónoma del Exploratorium Isabel Hawkins quien junto a la educadora del Exploratorium Liliana Blanco explican los movimientos de los astros durante un eclipse total de sol. A través de demostraciones, ellas muestran cómo la luna, el sol y la Tierra se alinean para crear la coincidencia cósmica que llamamos un eclipse total de sol.
Learn how the mix of saltwater and freshwater in the San Francisco Bay affects its diverse ecosystems with John Largier, professor of coastal oceanography at the University of California, Davis. Essential, explosive sodium is a soft, silvery alkali metal that roils in water, releasing clouds of hydrogen gas that fan its yellow flames. It reacts with most elements, and is naturally found only in compounds, such as sodium chloride, or common salt. Ancient Egyptians knew sodium from natron, a mix of salts prized for cleaning, personal hygiene, and preservation, particularly in mummification. Humphry Davy first isolated the element from caustic soda in 1807, naming it sodium; Jakob Berzelius preferred natrium, hence its symbol (Na). As a metal, liquid sodium cools nuclear reactors, and sodium-vapor lamps bathe streets at night in yellow, monochromatic light. In this video, Exploratorium Senior Scientist Paul Doherty explains why we don't have a total solar eclipse every month. A total solar eclipse happens when the moon crosses between the sun and Earth and casts its shadow onto our planet. But the orbit of the moon is tilted relative to the orbit of the Earth around the sun, so the moon often passes below or above Earth. At those times, it does not cross the line between the sun and the Earth, and therefore does not create a solar eclipse. There are just two times a year in the Earth's orbit when there is a possibility of a total solar eclipse.
Join Exploratorium astronomer Isabel Hawkins, and Exploratorium educator Liliana Blanco as they explain the celestial mechanics of a total solar eclipse. Through demonstrations, they show how the moon, sun, and Earth align to create the cosmic coincidence that we see as a total solar eclipse. The Exploratorium is sending a production crew thousands of miles by plane and by boat to Woleai, Micronesia, to broadcast a solar eclipse live to the world. Many factors went into choosing a destination for the broadcast. Executive Producer Robyn Higdon looked along the path of totality for this eclipse, which will start in Indonesia and sweep across the Pacific Ocean, to find a location with good weather predictions and solid land for setting up the telescopes. The Woleai Atoll in Micronesia was the perfect choice. Tune in on March 8th at 5:00 p.m. PST to watch the live broadcast! Learn how to cast images of the sun using nothing more than a piece of paper and your hands! Check out this D.I.Y. video on how to build your own sun viewer using items that you may have lying around your house. All you need is a pair of binoculars, a tripod, and a large piece of white paper or fabric to project the solar image onto.
This is the method used by Galileo himself!