1 / 10

Miscellaneous announcements…

Learn about the measurement of angles in the sky, the motion of the sun, and how it affects the seasons. Get started on your project and join an astrophotography session. Questions on motion are welcome!

bruben
Download Presentation

Miscellaneous announcements…

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. Miscellaneous announcements… • Homework 1 due today by 5:00. • Pick up Homework 2; solutions are on the web. • Get started on a project soon, if you haven’t already! • Astrophotographers: please see me after class. • Questions on motion of the stars? • Try out Sky View Café and/or Sky Chart III…

  2. The Sun and the Seasons 6 September 2006

  3. Today: • Measuring angles in the sky • How the sun moves through our sky • Seasons

  4. Measuring Angles

  5. A sunset photo (July)

  6. Equinox sunset

  7. Motion of the Sun • On any given day, the sun’s motion is essentially the same as that of a star (rises in the east, sets in the west). • The sun’s motion doesn’t quite keep up with the stars: It completes a 360º circle in 24 hours. • With respect to the stars, the sun appears to move once a year around a great circle, tipped 23.5º with respect to the celestial equator. • In late June (summer solstice), the sun is farthest north; in late December (winter solstice), the sun is farthest south. In late March and September (equinoxes), it’s on the celestial equator.

  8. Motion of the Sun Facing south

  9. Motion of the Sun Sun’s apparent path among the stars is called the ecliptic

  10. Seasons Summer Winter (A one-square-meter surface, directly facing the sun, receives about 1000 watts of power.)

More Related