AST101Lab3 - Name_Nate Christensen Astronomy 101 Online...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Name: ____Nate Christensen ___ Astronomy 101 Online - Seasons Lab Objective : When you have completed this lab, you should be able to describe the seasons of the year and explain the reasons for those seasons. Normally, we would use globes and spotlights to study the seasons on the Earth. If you have a flashlight and a ball, you are encouraged to reproduce what you will see in the web simulations and Starry Night. Vocabulary: : Terms used in this exercise include: Summer Solstice Winter Solstice Vernal Equinox Autumnal Equinox Horizon Latitude Longitude Zenith North Pole South Pole Tropic of Cancer Tropic of Capricorn Equator Arctic Circle Antarctic Circle Also: the word "seasons" suggests a change in the average weather from one time of year to another. Procedure : A. The Altitude of the Sun at Noon in Champaign: We know that there are four important days of the year when it comes to seasons. Here in the northern hemisphere, the first day of fall occurs around September 22nd (called the autumnal equinox). The first day of winter occurs around December 22nd (called the winter solstice). The first day of spring occurs around March 22nd (called the vernal equinox). The first day of summer occurs around June 22nd (called the summer solstice). We'll start by observing the sun using Starry Night. Start the program and set up the following initial conditions: Date: 9/22/2005 Daylight Savings Time: Off Time: 12:00:00PM Location: 40N, 88W (Champaign, Illinois) Time flow: Stopped Time Step: 001 days View Direction: south Go into the view menu and select "Hide Daylight" and "Celestial Grid". Use the slider bar to zoom in to 81° x 55° (or close to it). You should see the Sun high up in the southern sky. Click and drag the sky to ensure that the Sun is near the top center of the screen. You will see the sun at the intersection of two
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
grid lines, one running east-west (roughly left to right) and one running north-south (roughly top to bottom). 1 . What is the name of the east-west line on which the sun is currently located? __Celestial Equator 2 . What is the name of the north-south line on which the sun is currently located? __Celestial Meridian Recall that the celestial equator is just the extension of the Earth's equator into the night sky. What we will want to do next is to find out how high the sun is from the horizon. Zoom back out as far as you can. Put your cursor over the sun until it becomes an arrow. Click on the sun and hold the left mouse button down. While holding the mouse button down, drag the cursor along the celestial meridian, down toward the horizon. You should be drawing a line and Starry Night should be telling you the 'Angular Separation' or the length of the line in terms of an angle. Use the line to follow the Celestial Meridian until it strikes the horizon. You have just measured the altitude (angle above the horizon) of the sun. 3
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/06/2008 for the course ASTRO 100 taught by Professor Kaler during the Fall '08 term at University of Illinois at Urbana–Champaign.

Page1 / 7

AST101Lab3 - Name_Nate Christensen Astronomy 101 Online...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online