Month
Day of Year
Day of Month
Sunrise
Sunset
Moonrise
Moonset
High Tide(s)
Low Tide(s)
Average High Temperature
Average Low Temperature
Record High Temperature/Year in which record occurred
Record Low Temperature/Year in which record occurred

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. Calculate the number of hours of daylight by subtracting the time of sunrise from the time of sunset. Construct a line graph. [Hint: Before subtracting, times should be expressed in 24-hour format. Be careful--times are tricky to subtract!]

   Data Table - Duration of Insolation

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

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 same graph as in Question #1, Insolation (Incoming Solar Radiation) Versus Temperature].

   Data Table - Average High Temperature

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

   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
   

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

   
   
   

4. Refer to the preceding graph of hours of daylight and temperature versus time. In general, what is the relationship between number of hours of daylight and average high temperature?

   
   
   

1. In 1995, scientists discovered that reflected sunlight off a Full Moon causes the Earth to warm slightly. How many degrees warmer is the Earth during a Full Moon? [Hint: Refer to Strange Weather, Events, and Happenings for MAR 09.]

   
   
   

2. Did you know that the Full Moon each month has its own name? In the following data table, list 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.]

   Month	Date	Full Moon Name	Month	Date	Full Moon Name
   JAN	18		JUL
   FEB			AUG
   MAR			SEP		Full "Harvest" Moon
   APR			OCT
   MAY			NOV
   JUN			DEC

3. The Full "Harvest" Moon, named for the Full Moon occurring closest to the September Equinox, rises in the east soon after the Sun sets in the west. The additional light late into the evening allows farmers time to harvest their crops after sunset. The Harvest Moon usually occurs in September, but occasionally falls in October. In 2003, what is the date of the Harvest Moon?

   
   
   

4. The side of the Moon that faces the Sun is always lighted; as the Moon revolves around (orbits) the Earth, we are able to see more or less of the lighted side of the Moon. As a result, the Moon appears to change shape (i.e., phase) in a predictable cycle.
   1. For the month of JANUARY, record the dates of the phases of the Moon, as well as the times of moonrise and moonset:

      Moon Phase	Date	Moon Rise	Moon Set
      New Moon
      First Quarter
      Full Moon
      Last Quarter

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

      
      
      

   3. A simple model of the Sun-Earth-Moon system suggests that each Moon phase is visible from the side of the Earth that faces the Moon. Approximately how many hours is every Moon phase visible? Verify your answer by looking at the preceding data table--liberal rounding is encouraged!

      
      
      

   4. Approximately how many days does it take for the Moon to go through a cycle of phases, i.e., how many days pass from one New Moon to the next? [Hint: Refer to the preceding data table as well as the almanac page for February.]

      
      
      

5. Every year, Easter occurs on the first Sunday after the first Full Moon after the March (or Spring) Equinox.
   1. What date is the March Equinox?

      
      
      

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

      
      
      

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

   
   
   

6. 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?

   
   
   

Ocean tides are caused by the Moon's gravitational pull on the Earth.

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

   
   
   

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

   
   
   

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

   
   
   

4. As the Moon revolves around (orbits) the Earth, the time that tides occur is later by approximately how many minutes per day? [Hint: Carefully examine several consecutive days of tide predictions to look for a pattern.]

   
   
   

5. The greatest tidal range (the difference in height between consecutive high and low tides) occurs during the New Moon and Full Moon phases. For the month of MAY, on which dates will the tidal range be greatest?

   
   
   

6. Suppose 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 04 July 2003. There are two times; logically, which time would be better for shark tooth collecting? Explain why one of the times would be impractical.

   
   
   

1. You've probably heard the old saying, "March comes in like a lion (see MAR 01, page 18, almanac) and goes out like a lamb." Usually, this saying is used to describe typical March weather: in the beginning of March, the weather is often wild; by the end of March, the weather is usually mild. But this modern weather proverb actually originates from astronomy: in the late-February/early-March night skies, one well-known constellation (named after a lion) is rising in the east ("coming in") at the same time that another well-known constellation (named after a sheep or ram) is setting in the west ("going out"). Name these two constellations. [Hint: Part of one of the constellations (the "sickle") appears in the color plate for FEB 15-16, shown on page 56. Both constellations are signs of the Zodiac.]

   
   
   

2. Remember the mnemonic, Spring forward; Fall back? List the dates when Daylight Saving Time begins and ends. [Hint: Refer to the almanac for the months of April and October.]

   
   
   

3. The subsolar point is the point on the Earth's surface at which the Sun is at the zenith at local solar noon. On any given day, the subsolar point moves east-west along a single line of latitude as the Earth rotates counterclockwise. The latitude of the subsolar point varies between zero degrees (0°) at the equinoxes and ±23.5° at the solstices. The annual north-south migration of the subsolar point (caused by the tilt of the Earth's axis of rotation and the revolution of the Earth around the Sun) is one of the real reasons for the seasons. The endpoints of the migration route are marked by the solstices; the midpoint by the equinoxes. In the following data table, list the date and time of the equinoxes and solstices for 2003:

   Astronomical Event	Date	Time
   March Equinox
   June Solstice
   September Equinox
   December Solstice	22 DEC 2003

4. The word equinox literally means "equal nights," referring to either of two times during the year when the Sun crosses the plane of the Earth's Equator and day and night are of nearly equal length. List the number of hours of daylight & darkness on the dates of the equinoxes.

   
   
   

5. Groundhog Day is February 2nd. According to legend, if the groundhog sees his shadow on February 2nd, then there will be six more weeks of winter weather; if he doesn't see his shadow, then there will be an early spring. If astronomical spring begins on the March Equinox (in the Northern Hemisphere), then how many weeks after Groundhog Day is the official beginning of spring (regardless of whether the groundhog sees his shadow)?

   
   
   

6. Close examination of an almanac reveals that the latest sunrise and earliest sunset do not occur--as one would expect--on the December Solstice, the day with the fewest hours of daylight in the Northern Hemisphere. As it turns out, the earliest sunsets occur in early December (DEC 01-12, 2003) and the latest sunrises occur in late December/early January (JAN 01-10, 2003). [A similar situation occurs before/after the June Solstice.] Complete the following data table:

   Astronomical Event	Date	Sunrise (EST)	Sunset (EST)	Duration of Insolation (hh:mm)
   Earliest Sunset	12 DEC '03
   "Shortest" Day	22 DEC '03
   Latest Sunrise	01 JAN '03

7. Twilight (a.k.a. dawn & dusk) is the time period when the sky is lighted before/after the Sun rises/sets above/below the horizon. Civil Twilight usually lasts for approximately one-half hour. On 07 DEC 2003, approximately what time will dusk begin/end?

   
   
   

8. Twilight is a good time for planet-watching. Planets are among the brightest objects in the sky; in the evening, they are often the first objects to appear as the light of day fades to darkness (and vice versa in the morning). Five planets are visible in the sky with the unaided eye: Mercury; Venus; Mars; Jupiter; and Saturn. The planet Mercury is often difficult to see in the real sky because it always appears relatively close to the brightest object in the sky--the Sun. When would be a good date and time (approximately) to look for Mercury during 2003? [Hint: Mercury is visible either just before sunrise or just after sunset, depending upon where Mercury is located in its orbit around the Sun.]

   
   
   

9. Interactive sky charts are available online from Sky & Telescope magazine. What is the Universal Resource Locator (URL) for the Sky & Telescope Web site?