1 / 7

Chapter 21

Chapter 21. 21.4 Star Systems and Galaxies. Double and Triple Stars. Most solar systems have more than one star. Solar systems with 2 stars are called binary systems. Solar systems with 3 stars are called triple stars

valmai
Télécharger la présentation

Chapter 21

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 21 21.4 Star Systems and Galaxies

  2. Double and Triple Stars • Most solar systems have more than one star. • Solar systems with 2 stars are called binary systems. Solar systems with 3 stars are called triple stars • The stars orbit each other, and when one star passes in front of another star it is called an eclipsing binary system • The effects of gravity often clue astronomers to the presence of the 2nd star by a distinct wobble the star has when it orbits.

  3. Extrasolar planets • The pull of gravity is one of the ways that astronomers have used to discover planets orbiting other stars. A different more subtle wobble indicates the presence of planets. • More than 400 planets have been found orbiting other stars. • Technology is not good enough to detect Earth like planets yet, but it is getting better all the time.

  4. Galaxies • A galaxy is a collection of stars, dust, and gas that usually orbits a supermassive black hole and contains billions of stars. • There are 3 kinds of galaxies: • Spiral • Elliptical • Irregular

  5. Spiral Galaxies • Have a pinwheel shape. Our galaxy, the Milky Way, is a spiral galaxy

  6. Elliptical Galaxies • They are older galaxies that lack a lot of dust and gas. • Star formation has virtually ceased as a result.

  7. Irregular Galaxies • Galaxies that have odd shapes are called irregular galaxies. • The odd shapes come from collisions with other galaxies.

More Related