HOU Workshop

Spiral Galaxies have spiral arms that reach out from the center, or the nucleus, and wind around the galaxy. Spiral galaxies contain stars, gas, and dust. Often times large clumps of hot hydrogen gas, called HII (pronounced H2) regions, lie within the arms and are sites of new star formation. Our galaxy, the Milky Way, is a spiral galaxy.

Edge-On Spiral Galaxies and Face-On Spiral Galaxies are the same type of galaxy but the name depends on their orientation in the sky. If we see them from the side, then we call them edge-on...if we see them looking down from one of the poles then we call them face-on. Many spiral galaxies are neither exactly face-on or edge-on but rather somewhere in between.

Elliptical Galaxies have no spiral arms structure, but rather an elliptical or spherical shape. Elliptical galaxies contain many stars and clusters of stars, but have very little gas and dust.

Below are examples of an edge-on spiral galaxy, a face-on spiral galaxy, and an elliptical galaxy. The images here include foreground stars, which are part of our own galaxy. The examples provide the name, type, and the constellation where the galaxy can be found. On the following pages you will be asked to determine the types of several other galaxies based on these examples.

	Name: M51, NGC5194, The Whirlpool Galaxy Type: Face-On Spiral Constellation: Canes Venatici
	Name: M104, NGC4594, The Sombrero Galaxy Type: Edge-On Spiral Constellation: Virgo
	Name: NGC4636 Type: Elliptical Constellation: Virgo

Classify some more galaxies

Gorgeous Galaxies Activities

HOU ISE Activities

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