Notes Observing space

Early astronomy From Earth, you observe stars, some planets, the changes in the Moon, eclipses, and other events like comets and meteor showers just by looking up at the night sky. People have been tracking the changes and movements in the night sky for thousands of years.

Early astronomy Many cultures have noticed similar patterns and created different stories to explain those patterns.

In both Asian and Aztec folklore, a rabbit lives on the moon. Moon rabbit In both Asian and Aztec folklore, a rabbit lives on the moon. They both noticed a pattern that they thought looked like a rabbit on the Moon, which is where the legend came from.

In ancient Egypt, the Moon was seen as a god named Khonsu.

The term planet comes from the Greek word that means “wanderer.” Early astronomy The term planet comes from the Greek word that means “wanderer.” Greek astronomers named them because of how much they move compared to other objects in the sky.

Early astronomy Because the stars, planets, and Sun APPEAR to move around Earth, early astronomers assumed Earth was at the center of the universe (geocentric model).

Nicolas Copernicus (1473-1543) Early astronomy Nicolas Copernicus (1473-1543) First astronomer to propose that the Sun is the center of our solar system (Heliocentric model) Earth revolves around the Sun once per year and rotates once per day.

constellations Early astronomers recognized and named some familiar objects in the night sky. Ancient Greek astronomers named the 5 brightest planets after their gods, and also named many of the familiar patterns we see in the stars.

Constellation- a group of stars that form a pattern in the sky. constellations Constellation- a group of stars that form a pattern in the sky.

Some major constellations visible in the Northern Hemisphere are..

Named after Orion, a hunter in Greek mythology. constellations 1. Orion Named after Orion, a hunter in Greek mythology. Visible in AZ (Northern Hemisphere) in Winter

2. Ursa Major (Great Bear) constellations 2. Ursa Major (Great Bear) Best known for containing the Big Dipper Visible in the Northern Hemisphere all year long.

3. Cygnus constellations Name comes from the Latin for “swan.” Visible in AZ (Northern Hemisphere) in Summer

4. Scorpius constellations Zodiac constellation Its name is Latin for “scorpion.” Visible in AZ (Northern Hemisphere) in Summer

5. Cassiopeia constellations Named after Queen Cassiopeia in Greek mythology. Has a distinctive “M” shape. Visible in AZ (Northern Hemisphere) all year.

Areas of the night sky are named after constellations. An object is said to be “in” that constellation even if it is not one of the stars that make the shape.

constellations If you want to find a particular place in the U.S., it helps to know what state it’s in.

Scientists use a similar system for mapping objects in the sky. constellations Scientists use a similar system for mapping objects in the sky. The sky has been divided into 88 areas named for the constellations.

constellations This allows astronomers to locate newly discovered objects and “map” them in the sky so other astronomers can find them.

constellations Stars in a constellation may not be physically close to one another- they only look that way from our perspective.

earth rotation You cannot see all the constellations at once because Earth blocks half of space from your view at all times.

Each night, the stars seem to move across the sky. earth rotation Each night, the stars seem to move across the sky. This is because of Earth’s rotation. http://www.space.com/24324- breathtaking-night-sky-time- lapse-video.html

earth rotation Above the North Pole is a star called Polaris (North Star). Polaris seems to stay in the same spot as all the stars around it rotate, because it is directly “above” Earth as it spins.

Movement of space objects Stars are always moving, but they are so far away that you cannot see their movements. It takes thousands and thousands of years for stars to move enough to change the shape of a constellation.

Movement of space objects Constellations allow us to observe the movement of objects that are close to Earth, like the Moon and other planets of our solar system.