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00:20:07
Neon is normally odorless and colorless, reacting with no one, not even itself. Abundant in the universe, uncommon on Earth, it drifts aloof from any bond. When isolated by Sir William Ramsay and Morris Travers inside a vacuum tube in 1898, the noble gas betrayed its excitement in brilliant red. That excitement, glowing within Georges Claude’s ingeniously curved lamps since 1923, has captured our imaginations ever since.

00:23:05
At the center of each chlorophyll molecule sits one magnesium ion, a linchpin for photosynthesis. Our cells require magnesium for hundreds of enzymes and metabolic processes. Spawned from supernovae and scattered through interstellar dust, this life-giving alkaline earth metal readily reacts and is abundant in seawater and a host of minerals from dolomite to olivine.

00:38:13
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.

00:32:10
Neon is normally odorless and colorless, reacting with no one, not even itself. Abundant in the universe, uncommon on Earth, it drifts aloof from any bond. When isolated by Sir William Ramsay and Morris Travers inside a vacuum tube in 1898, the noble gas betrayed its excitement in brilliant red. That excitement, glowing within Georges Claude’s ingeniously curved lamps since 1923, has captured our imaginations ever since.

00:05:26
Join Exploratorium staff scientist Ron Hipschman as we visit Dan Werthimer, Director of the SETI Research Center at UC Berkeley. SETI conducts experiments searching for electromagnetic signatures of intelligent extraterrestrial civilizations, spanning wavelengths from radio to visible light, over ten orders of magnitude in characteristic time scale.

00:14:00
How can a bugle make so many notes even though it has no valves? We’ll find out about how waves can fit into pipes, strings and rods in this webcast.

00:08:20
Join Ron Hipschman at a live webcast where he’ll investigate sound waves, interference, beats, and harmonics. What is sound? How high a pitch can you hear? Can two sounds add up to no sound? Explore these questions and more in this resonant presentation.

00:10:00
What is sound? How high a pitch can you hear? Can two sounds add up to no sound? Explore these questions and more in this resonant presentation.

00:35:00
Listen as we demonstrate what all those sound jargon words mean. If you’ve ever wondered what frequency, wavelength, amplitude and other words of sound mean, we’ll explore them in this demo-packed webcast.