STAR SYSTEMS AND GALAXIES

SPACE SCIENCE

Star Systems and Planets

Our solar system has a medium sized star, the sun. More than half of all stars are members of groups of two or more stars, called star systems. Stars systems with 2 stars are called binary stars.

Alpha Centauri A and Alpha Centauri B

Proxima Centauri is a triple star system close to our sun. To see a planet directly, astronomers will have to shield their view from the glare of the star that the planet revolves around.

Galaxies

Our solar system is located in the Milky Way Galaxy

A galaxy contains single and double stars, star systems, and lots of gas and dust.

The dark blotches in the Milky Way are clouds of dust that block light coming from stars behind them

Astronomers have classified most galaxies into 3 main categories: spiral, elliptical and irregular

Milky Way

Spiral Galaxies

Appear to have arms that spiral outward, like pinwheels

Milky Way galaxy is a spiral galaxy The center of our

galaxy is about 25,000 light-years from the sun

The center is hidden from our view by massive clouds of stars, gas, and dust between the sun and the center.

Elliptical Galaxies

Appear like flattened balls. Contain billions of stars but have little gas and dust between the stars New stars cannot form in elliptical galaxies because of the lack of gas and dust

Irregular Galaxies

Some galaxies do not have regular shapes

The Large Magellanic Cloud is an irregular galaxy about 160,000 light-years away from our galaxy.

Exit Ticket

Describe the three main types of galaxies.