The Unofficial Student Activity for
Bob Ryan's 1999 Almanac & Guide for the Weatherwise

by Walter Sanford
Planetarium Teacher, Sandburg Center for Sky Awareness
Fairfax County Public Schools

(Teacher's Answer Key available upon request.)

Increase your sky awareness by answering the following activity questions.

Personal Almanac Data

Duration of Insolation (Number Hours Daylight)
versus Average Temperature

  1. In the following data table, record the duration of insolation (number of hours of daylight) in Washington, D.C. for the 21st of each month. To calculate the number of hours of daylight, subtract the time of sunrise from the time of sunset. (Hint: Before subtracting, times should be expressed in 24-hour format. Be careful--times are tricky to subtract!) Construct a line graph.

    Data Table - Duration of Insolation

    Month | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC 
------|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----
# Hrs |     |     |     |     |     |     |     |     |     |     |     |

    Line Graph: Duration of Insolation & Average High Temperature
    Washington, D.C.

    H  16 --|
O      -|
U  15 --|
R      -|
S  14 --|                                               |-- 90  T
       -|                                               |-      E
D  13 --|                                               |-- 80  M
A      -|                                               |-      P
Y  12 --|                                               |-- 70  E
L      -|                                               |-      R
I  11 --|                                               |-- 60  A
G      -|                                               |-      T
H  10 --|                                               |-- 50  U
T      -|                                               |-      R
   09 --|-----------------------------------------------|-- 40  E
        | J | F | M | A | M | J | J | A | S | O | N | D |
                          MONTHS OF YEAR

  2. In the data table below, record the average high temperature in Washington, D.C. for the 21st of each month. Construct a line graph (using the graph in Question #1, Temperature & Precipitation - What's Average and What's Unusual).

    Data Table - Average High Temperature

    Month | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC
------|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----|-----
Temp. |     |     |     |     |     |     |     |     |     |     |     |

  3. In the northern mid-latitudes, the Winter Solstice occurs on the day with the fewest hours of daylight. Based upon the Duration of Insolation Data Table, what is the approximate date of the Winter Solstice?

  4. The word equinox literally means "equal nights." Explain why the Spring and Fall Equinoxes (MAR 21 and SEP 21 respectively) are named appropriately. (Refer to the Duration of Insolation Data Table.)

  5. In Washington, D.C., on average, which month is the COLDEST? The HOTTEST?

  6. The point at which the Earth is farthest from the Sun is known as aphelion.
    1. In 1999, when is the Earth at aphelion? (Refer to The Night Sky in 1999.)

    2. When the Earth is at aphelion, why is it Summer in the Northern Hemisphere? (Refer to the line graph of Duration of Insolation & Average High Temperature in Washington, D.C.)

Sky Awareness (including Astronomy)

  1. For the MONTH IN WHICH YOU WERE BORN (e.g., August), list THREE astronomical phenomena that you may observe in the night sky in 1999.
    1. MONTH ____________________


  2. Have you ever seen a "shooting star?" Shooting stars are actually meteors--small pieces of solar system debris, usually sand-sized particles, which vaporize while colliding at great speed (up to 40 miles per second) with the Earth's atmosphere. Annual "meteor showers" (up to several meteors per minute) occur when the Earth's orbit crosses the orbits of comets. Most annual meteor showers are named for the constellation from which the meteors appear to radiate. In the following data table, record the dates of several of the more productive annual meteor showers.

    METEOR SHOWER NAME DATE (Month/Day)
    Perseid
    Leonid
    Geminid

  3. "Once in a Blue Moon" a "Blue Moon" occurs. What is a Blue Moon? (Refer to The Night Sky in 1999, specifically January and again in March.) How old will you be the next time there are two Blue Moons during the same year?

  4. For the month of FEBRUARY, record the dates of the phases of the moon. Why is there no Full Moon in February?

  5. What is the difference in appearance between the First and Last Quarter Moon?

  6. The "Harvest" Moon is the first Full Moon after the Fall (or Autumnal) Equinox (September 23rd). In 1999, what is the date of the Harvest Moon?

  7. Did you know that the Full Moon each month has its own name? In the following data table, enter the date and name of the Full Moon for each month. [Hint: Refer to PHASES OF THE MOON (listed at the bottom of each month) for the date of the Full Moon; for that date, look under Strange Weather, Events, and Happenings for the name of the Full Moon. Also note the typographical error for the date of the August Full Moon.]

    MONTH DATE FULL MOON NAME MONTH DATE FULL MOON NAME
    JAN

    		JUL

    FEB None "Snow" Moon AUG

    MAR
    		"Sap" or "Lenten" Moon SEP
    		"Harvest" Moon
    APR

    		OCT

    MAY

    		NOV

    JUN

    		DEC

  8. Almost every year, Easter occurs on the first Sunday after the first Full Moon after the Spring (or Vernal) Equinox.
    1. What date is the Spring Equinox?

    2. On what date is the NEXT Full Moon AFTER the Spring Equinox?

    3. What date is Easter Sunday? (If necessary, refer to a calendar.)

  9. What is astronomically significant about June 21st, 1999 at 3:49 p.m.?

  10. If the distance around the Capital Beltway (I-495/95) is 66 miles, and the distance to the moon is approximately 240,000 miles, then how many times would you have to go around the beltway to "travel to" the moon?

  11. Most days, how many high tides occur? Approximately how many hours apart?

  12. Most days, how many low tides occur? Approximately how many hours apart?

  13. Approximately how many hours pass between one high tide and the next low tide?

  14. The greatest tidal range (difference between high and low tide) occurs during the New and Full Moon phases. For the month of May, on which dates should the tidal range be greatest?

  15. Assume that you would like to go fossil shark tooth collecting along the Potomac River near Colonial Beach, VA, and you know that the best time to go collecting is during low tide. Use the "Tide Correction Table" on page 2 of the almanac to find the best times to go collecting on 4 July 1999. There are two times. As a practical matter, which time would be better?

Left Your Watch Behind?
by Dr. Michael C. MacCracken

  1. How can you tell when it is midday (apparent local noon)?

  2. Describe the "star-hopping" trick which can be used to find Polaris, the North Star.

  3. To tell time by star-gazing, what three pieces of information are needed?

Tom Kierein's Top 10 "Fast" Facts

  1. In miles per hour (mph), what is the Earth's speed as it orbits the Sun?

  2. In miles per hour (mph), what is the moon's speed as it orbits the Earth?

  3. In miles per hour (mph), what is the Space Shuttle's speed as it orbits the Earth?

  4. In miles per hour (mph), what is the speed of the Solar System as it orbits the center of the Milky Way galaxy?

Copyright © 1999 by Walter Sanford. All rights reserved.
AMS Education Initiatives | Printing Tips | Teacher's Answer Key | Comments/Suggestions?
WeatherNet4 | Online Geoscience-Related Activities | Geosystems in FCPS