Secret Language: Cryptography & Secret Codes | Exploratorium
WEBThe algorithm or method used to encipher the original message (known as the plaintext). The key used with the algorithm to allow the plaintext to be both enciphered and deciphered. The period or time during which the key is valid. By way of analogy, to get into your home you would put a key in a lock to open the door.
Anatomy of an Egg - Exploratorium
WEBBumpy and grainy in texture, an eggshell is covered with as many as 17,000 tiny pores. Eggshell is made almost entirely of calcium carbonate (CaCO 3 ) crystals. It is a semipermeable membrane, which means that air and moisture can pass through its pores. The shell also has a thin outermost coating called the bloom or cuticle that helps keep out ...
A Brief History of Pi (π) - Exploratorium
WEBHere’s a brief history of finding π. The ancient Babylonians calculated the area of a circle by taking 3 times the square of its radius, which gave a value of pi = 3. One Babylonian tablet (ca. 1900–1680 BC) indicates a value of 3.125 for π, which is a closer approximation. The Rhind Papyrus (ca.1650 BC) gives us insight into the ...
Origins: CERN: Ideas: The Big Bang - Exploratorium
WEBThe universe began, scientists believe, with every speck of its energy jammed into a very tiny point. This extremely dense point exploded with unimaginable force, creating matter and propelling it outward to make the billions of galaxies of our vast universe. Astrophysicists dubbed this titanic explosion the Big Bang.
What Causes a Solar Eclipse? | Exploratorium
WEBA solar eclipse occurs when the moon passes between the Sun and Earth, casting the moon's shadow on Earth. This only happens occasionally, because the moon doesn't orbit in the exact same plane as the Sun and Earth do. Two things need to occur at once for you to see a solar eclipse: the Sun, moon, and Earth need to be in a straight line, with ...
Total Solar Eclipse 2024 Time & Path | Exploratorium
WEBBe ready. On April 8, 2024, a total solar eclipse will be visible in the continental United States. Glimpse the full glory of the Sun’s outer atmosphere, or corona, visible only when the Sun’s disc is completely covered by the moon. Credit: Romeo Durscher/NASA.
Build a Solar System Model | Exploratorium
WEBIf you build your solar system on a roll of toilet paper, you can make the Sun about .4 inches (10 mm) across and still fit the entire solar system on the roll. A standard roll of toilet paper has about 450 sheets that are about 4.375 inches long, hence the roll is about 164 feet long. You should check your toilet paper for length.
Naked Egg: Biology & Chemistry Science Activity | Exploratorium
WEBAdd vinegar to cover the eggs (see photo below), and cover the container. Allow the eggs to sit for 24 to 48 hours at room temperature. Note: Changing out the vinegar halfway through and replacing it with fresh vinegar will speed up the process. The eggshells will leave residue in the vinegar bath (see photo below).
What is Inquiry? - Exploratorium
WEBInquiry-based science is a teaching approach that encourages students to explore scientific concepts through hands-on investigations, questions, and critical thinking. This process is driven by the learner’s curiosity and sustained by their sense of ownership of the process. But curiosity and ownership alone are not enough to ensure a ...
Popping Popcorn - Exploratorium
WEBThe combination of a hard seed coat, starch, and water are critical to how popcorn gets its pop. As a popcorn kernel is heated, water and oil inside the seed heat up and soften the surrounding starch. The surrounding shell is so tough that the water can’t escape when it initially boils into steam. As the steam gets even hotter, the water ...