1 / 5

Celestial Navigation I

Celestial Navigation I. Calculating Latitude By Observing Heavenly Bodies. Geographical Position (GP). Imaging a line linking a heavenly body and the center of the earth. The point where this line cuts through the earth is the body’s Geographical Position (GP).

felix
Download Presentation

Celestial Navigation I

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. Celestial Navigation I Calculating Latitude By Observing Heavenly Bodies

  2. Geographical Position (GP) Imaging a line linking a heavenly body and the center of the earth The point where this line cuts through the earth is the body’s Geographical Position (GP)

  3. Geographical Position (GP) If you are not at the GP when you look up you only see your own zenith, and not the body in question To you the body is at a different elevation in the sky. The angle between the body and your own zenith is the zenith distance A person who stands at the GP of a body would look straight up to see that body.

  4. Altitude & Declination You are at a point due North of the GP. To see the star you look to the SOUTH The horizon line is a tangent to the earth that passes through your position Ad Astra → You are HERE Z P The altitude is the angle of elevation you measure for the star above the horizon ALT GP DEC The declination of a heavenly body is simply the latitude of its GP. This information is available to Navigators in published logs. E

  5. P Z E Altitude & Declination We must also consider the fact that the tilt of the Earth changes seasonally as the Earth orbits the sun…… Ad Astra → GP The GP (and so the declination) of a star thus changes throughout the year. It is important that any navigator has up to date charts that give declinations on a daily basis.

More Related