Welcome to http://www.handsonuniverse.org/activities/Explorations/Galaxies

We see Milky Way Galaxy from the inside! When we look toward our galactic center, we see a "milky way" made of billions of stars. The center of the Milky Way is in the direction of the constellations, Sagittarius and Scorpius. Dust clouds block our view of the very bright galaxy core.  We don't see the Milky Way's spiral shape because our view is from the inside! Our Sun and thus our Solar System are located about two thirds of the way away out from the center of the galaxy.  We live in on the inside edge of a spiral arm called the Orion Arm.

Spiral Galaxies  Looking with telescopes, we see beautiful spiral galaxies. Our view lets us see some galaxies "face-on". We think our Milky Way has a spiral shape similar to these galaxies.

The Andromeda Galaxy is a close spiral neighbor. Andromeda is a spiral galaxy in our local neighborhood in space. It is 'only' 2.2 million light years away! You can find it with binoculars in the constellation of Andromeda. In dark skies, you can even see it as a fuzzy patch without binoculars!   It is the only object we can see with our unaided eyes from the Northern Hemisphere that is outside our own Milky Way Galaxy.

We see dust lanes when we view spiral galaxies 'edge on'.  Notice the dust lanes in these two spiral galaxies. The bright parts are the central galaxy cores. We are looking at the Sombrero Galaxy from the side or edge, rather than from above or below.

Elliptical galaxies have spherical shapes.   Irregular galaxies have odd shapes. M87 is an elliptical galaxy with a jet coming out the side.    Neither of these galaxies have a spiral shape.  Elliptical galaxies are shaped like spheres.  Irregular galaxies have odd shapes and are probably the result of galaxy collisions.  M82 is an irregular galaxy, sometimes called the Starburst Galaxy.

• The Galaxy Mystery Folder  contains .fts images of these galaxies numbered rather than named so you could try a matching game.  Open each numbered galaxy.  Pick out your favorites, write down the display parameters you like (color, min/max, etc.) and then figure out which ones they are by referring to this webpage. 

• ** HOU Educators:  Download .fts  images of the galaxies on this page. 

• Think about the spiral arms of spiral galaxies as Spiral Waves.  Images of three beautiful spiral galaxies were taken by CARA Space Explorers at Yerkes Observatory in the summer of 1999.  Use the slice tool to investigate the spiral arms as density waves.  

01/08/2000

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