Journey North Mystery Class Spring 2005

Mystery Class Update: February 25, 2005

Today's Report Includes:

Locations in Line after the Fourth Time?
Counting Down to the Longitude Clues--Two Weeks to Go
Teacher Tips for the Longitude Clues
Try This! Eggstraordinary Equinox Experiment
Untilt-a-World: Response to CQ #2
This Week's Sunrise/Sunset Times
Have You Marked Your Calendars?

Locations in Line after the Fourth Time?
The fourth set of sunrise/sunset data has arrived, once again, right on time. Now are your graphs revealing which locations are the farthest north? The farthest south? The closest to the equator? Are you able to list the locations in a north-south order? Where does your hometown fit in that order? The ten secret sites wish they could tell you more!

Counting Down to the Longitude Clues--Two Weeks to Go
Last week, we introduced you to mapping with Latitude and Longitude (the "global grid"). This week, we offer two more lessons to help prepare for the March 11 Longitude Clues.

The lessons below will you understand two important central concepts for the Longitude Clues:

(1) GMT or Universal time keeping:

What is GMT Time Keeping?

(2) And that "sunrise" and "sunset" don't result from sun movement. Instead, Earth spins one complete rotation (360 degrees) on its axis every 24 hours, which brings an area of Earth into the light of the sun in the morning and then out of it in the evening.

Does the Sun Really Rise and Set?

Teacher Tips for the Longitude Clues
Three Mystery Class veterans suggest that some other advance preparations for the Longitude Clues is time well spent:

Teacher Tip #1: Washington, D.C. Teacher Kathleen Isaacs recommends two books to get students orientated to longitude before the clues arrive:

Longitude & Literature

Teacher Tip #2: Texas Teacher Jo Leland has her students practice on the Longitude Clues for some of last year's Mystery Classes, and suggests that students mark a "longitude place marker" on their maps:

Longitude Place Marker

Teacher Tip #3: Florida Teacher Allison Bailey shares tips for "Rappin'" your way to understanding Longitude:

Rappin' and Rhyming With Longitude

Try This! Eggstraordinary Equinox Experiment
The upcoming Longitude Clues will coincide with the Vernal Equinox, March 20, a day when Astronomers (and our calendars) tell us it's Spring! On the Equinox, the amounts of day and night are of roughly equal length--approximately 12 hours each. There's a "balance" of light and dark at almost all locations on Earth.

Some people believe that there is another kind of "balance" on the Equinoxes, a special kind of force that will make a raw egg balance on its own end! Do you think this is true? Is there some sort of cosmic "balance" that makes eggs stand on their own on the Equinoxes, but not on other days? Is there a scientific way for you to test this?

Try this Eggceptional experiment before, during and after the Equinox!
The "Powers" of the Equinox

Untilt-a-World: Response to Challenge Question #2
Last week we asked "What do you think your climate and seasons would be like if the Earth wasn't tilted on its axis?" The tilted axis is shown on this drawing:

Congratulations to all of you who wrote in to explain that if the Earth were not tilted on its axis, we would not experience any seasonal changes.

There would still be different climates in different areas on earth (e.g., always cold at the poles and always hot at the equator); but each area's climate would remain constant throughout the year.

Luke from Vermont explained this very well:
"The tilt of the earth in comparison to the Sun causes there to be different seasons. As Earth circles the Sun, the earth's tilt causes the angle of the Sun's rays to be different at different places on the Earth. Where the Sun's rays strike the Earth's surface less directly, this causes winter there. The opposite effect occurs on the other side of the equator. If there was no tilt, the angle of Sun's rays would never change at a location, and there would be no seasons."

This Week's Sunrise/Sunset Times
Remember, the secret Mystery sites recorded their times last Monday, the same day you collected your own local sunrise/sunset data.

Link to This Week's Sunrise/Sunset Data

Have You Marked Your Calendars?
Here's the 2005 Mystery Class Schedule so you know what to expect from Journey North. Please be sure to plan ahead.

February 4- April 15:	Each Friday, Sunrise/Sunset Times are posted for the ten Mystery Sites.
March 11:	The "Longitude Clue" is posted.
March 18, 25, April 1, 8 & 15:	Interdisciplinary clues from the Mystery Sites are posted each week. (Please Note--out of fairness to all participants, we will only post the clues on their scheduled dates.)
April 22: Deadline for Your Answers!	No late entries will be accepted (out of fairness to all participants, no exceptions.)
April 29:	Mystery Sites Revealed!
May 6:	Meet Your Mystery Friends!

Questions? See Mystery Class FAQ's

The Next Mystery Class Update Will Be Posted on March 4, 2005