PURPOSE: to learn about the methods and tools used by astronomers to map the night sky

MATERIALS: calculator, SC001 Star Chart, planisphere patterns, scissors, tape/glue

INSTRUCTIONS: complete your prelab, print out these pages and complete the activities below

2.1. (6 pts) For each terrestrial grid line listed below, record the letter associated with its correct location
on the earth diagram :

Equator	0° latitude
Prime Meridian	0° longitude
Artic Circle	66.5° N latitude
Antarctic Circle	66.5° S latitude
Tropic of Cancer	23.5° N latitude
Tropic of Capricorn	23.5° S latitude

2.2. (6 pts) For each celestial sphere component listed below, record the letter associated with its correct
location on the celestial sphere diagram:

Earth's axis
celestial equator
North Celestial Pole
South Celestial Pole
ecliptic
Vernal Equinox

2.3. (1 pt) The ecliptic is defined as which of the following?

 a)   axis of Earth
 b)   location of celestial equator
 c)   where the vernal equinox is
 d)   plane of Sun

2.4. (1 pt) How many degrees separate the celestial equator and ecliptic?

 a)   25.8°
 b)   0°
 c)   23.5°
 d)   90°

2.5. (1 pt) The zenith is :

 a)   the direction of the equator
 b)   the point directly overhead the observer
 c)   a line drawn from the northern to southern horizon
 d)   the point directly north of the observer

2.6. (1 pt) In which two directions must you look to locate the meridian:

 a)   east and west
 b)   north and south
 c)   north and east
 d)   west and south

2.7. (3 pts) Print out this page of celestial spheres. On each, mark the observer's zenith with a letter 'Z'.
and draw in the observer's horizon on each. Be sure to turn this page in along with your lab activities.




SECTION 3 ACTIVITIES :

3.1. (2 pts) Write the following local EST times in military style:

a) 8:33 PM   ________________       b) 10:14 AM   ________________

3.2. (2 pts) Convert the following local EST times to Universal time (UT):

a) 16:51 PM   =  _______________ UT       b) 10:14 AM   =   _______________ UT

3.3. (2 pts) Convert the following UT times into local EST time (miltary style):

a) 03:42 UT   =   _______________ EST        b) 16:25 UT   =   _______________ EST

3.4. (1 pt) Declination and right ascension are analogous to ____________ and ____________.

 a)   azimuth/altitude; latitude/longitude
 b)   altitude/azimuth; universal time/sidereal time
 c)   altitude/azimuth; latitude/longitude
 d)   azimuth/altitude; universal time/sidereal time

3.5. (1 pt) A star has a position of RA: 16h 45m and DEC: -35° 25'. In which two directions (with
respect to the celestial equator and vernal equinox) is it located?

 a)   south and east
 b)   north and west
 c)   south and west
 d)   north and east

3.6. (3 pts) The star Vega was observed in Miami (L = +25.8°) when it was at its highest. It's hour angle
was h = 300°. Its coordinates are DEC = +38.8° and RA = 18.6h. What was Vega's altitude?

3.7. (3 pts) Convert the DEC coordinate 84° 47' 30" into units of time (hours). (HINT: convert the
smallest unit into the next smallest and add them, and so on until you have just units of xx.xx degrees
... then convert that result into x.xx hours). Show all your work.

3.8. (3 pts) Convert the RA coordinate 05h 06m 08s into units of angular distance. (HINT: convert the
smallest unit into the next smallest and add them, etc. until you have just units of x.xxx hours ... then
convert that into xx.x degrees).

-------------------------------------------------
**EXPERIMENT**
Now let's visualize the celestial sphere with the "Apparent Movement of A Star" applet, © W. Fendt.

3.9. (1 pt) Open the applet and press 'Reset'. Enter the terrestrial coordinates for Miami (longitude =
80.2° west, latitude (L) = 25.8° north) and press 'Enter'. Then enter today's date and a time of 00:00 h
UT (7 PM EST) and press 'Enter'. Notice the position of the marked star (ST). Record its data below:

Declination:
Altitude:

3.10. (1 pt) Now press 'Rotation/Pause' and watch as the star rises and crosses the sky throughout the
night. Towards which direction does the star appear to rise? set?

3.12. (1 pt) Now press 'Reset'. Notice that the latitude has been changed to L = 50° north which is
almost near the city of Calgary, Canada. Notice the starting position of the star (ST) is different.
Record the data:

Declination:
Altitude:

3.13. (1 pt) Restart the simulation and let the star cross the sky. Stop the simulation when the star sets.
Record the time:

3.14. (2 pts) Based on this experiment, is the apparent path of the star longer or shorter at higher
latitudes? Give a physical reason for this.

3.15. (2 pts) Experiment with the applet. Based on this, do you think that observers in the southern
hemisphere observe the same celestial objects on a given night as observers in the northern
hemisphere? Why or why not?

4.1. (6 pts) Use the SC001 Star Chart provided to name the object and constellation corresponding
to the data.

a) RA: 06h 45m   DEC: = -16°   _______________________    _______________________

b) RA: 19h 51m   DEC: = +08°   _______________________    _______________________

c) RA: 11h 02m   DEC: = +56°   _______________________    _______________________

d) RA: 03h 08m   DEC: = +40°   _______________________    _______________________

e) RA: 16h 30m   DEC: = -26°   _______________________    _______________________

f) RA: 22h 58m   DEC: = -29°   _______________________    _______________________

4.2. (1 pt) Notice the thick arched line that extends across the whole star chart. Notice the dates on it.
What does this line represent?

4.3. (1 pt) Using the arched line, what is the approx. RA / DEC of the Vernal Equinox (~ March 20^th)?

4.4. (2 pts) Estimate the RA and DEC of the Sun for today's date.

4.5. (2 pts) Look at the SC001 Star Chart closely. Other than object coordinates and location, list two
other pieces of information you can obtain from a star chart.

4.6. (5 pts) Print out the blank star chart grid here. On it, plot and label the following objects. Be sure to
turn this page in along with your lab activities.

OBJECT		RA	DEC
a) Betelguese - a star in Orion		05h 55m	+07° 24'
b) Regulus - a star in Leo		10h 08m	+11° 58'
c) NGC 2683 - a spiral galaxy in Lynx		08h 53m	+33° 25'
d) M1 - a nebula near Taurus		05h 35m	+22° 01'
e) NGC 2392 - a nebula in Gemini		07h 29m	+20° 55'

-------------------------------------------------
**EXPERIMENT**
Now you will construct a planisphere using patterns supplied by your TA. Follow the instructions below:

Step 1: Cut out star wheel along solid black line.
Step 2: Cut out star finder pattern along solid black line. Be sure NOT to cut off the tabs.
Step 3: Cut out the circular region in the center of the star finder pattern carefully.
Step 4: Fold pattern along dotted lines and tape or glue the tabs down.

To use your planisphere, all you need to do is turn the star wheel until the observing date lines up with
the correct local (EST) time. (If Daylight Savings Time is in effect - April to October - then you must
subtract an hour when using your planisphere). Hold the planisphere in front of you with the 'north'
corner pointing towards your body if you are facing north; the 'east' corner if you are facing east, etc.
The 'corners' represent the horizon in that direction. (When doing outdoor observing, you need to
flip the planisphere and hold it over your head so you can read it properly). Now locate objects:

4.7. (1 pt) In which direction (clockwise or counter-clockwise) must you turn the star wheel in order to
make constellations appear to rise in the east and set in the west over time?

4.8. (1 pt) If you observe at 2:00 AM EST on Sept. 25^th, is the constellation Draco near the northern or
southern horizon?

4.9. (1 pt) If you observe at 06:00 UT on July 15^th, what constellation almost directly at the zenith
and containing a VERY bright star could be used as a reference point?

4.10. (1 pt) During what month will the constellation Andromeda be on the meridian at 8:00 PM EST?

4.11. (1 pt) During what season is Orion found in the east around midnite EST?

4.12. (1 pt) At what approx. time on March 21^st does the bright star in the constellation Bootes rise?

4.13. (1 pt) Locate the zodiac constellations (see Table 1 in lab text) on your planisphere. What do
you notice about their relative positions and their path across the sky?

4.14. (2 pts) If you observe May 12th at 9 PM EST, name 2 constellations you can see in the north.

4.15. (2 pts) If it is Jan. 5^th at 4:00 UT, name 2 constellations you can observe in the west.

4.16. (2 pts) Find the star Polaris. It is the tail star of the constellation Ursa Minor. Watch it as you spin
the planisphere star wheel. What do you notice about it? Why is this important in celestial observing?

-------------------------------------------------
**EXPERIMENT**
Let's look at one final tool astronomers use : "Sky View Café" applet v. 3.0.10 © K. Shetline.

Open the the applet and familiarize yourself with it. You may need to enlarge your internet browser
window in order to see the entire applet successfully. Here are some major items to notice:

- At the top of the applet a window shows the date and time for which you would like to get data. You
can have the applet update itself while you work if you click the box labeled 'Track current time'.

- To the right of the image frame is your 'Location Settings.' These should already be set for Miami.
If not, enter them as follows:     LATITUDE : 24° 47' N,    LONGITUDE : 080° 19' W,   
TIME ZONE : UT - 5(EST),    DST rules for : North America

- The 'Sky' tab (which is the default view in the image frame) shows the sky that is visible for the date
and time selected. You can add in important features like the celestial equator, ecliptic, path of Moon
or Sun, and major constellations by checking the appropriate box or boxes in the 'Options' list to the
right of the image frame. 'Daylight/twilight' and 'Refraction effect' should already be checked by default
... do not change these. Any major Solar System objects visible are color and shape coded in the
applet as follows:

Sun - yellow circle    ; Moon - white/blue circle
Mercury - gray box    ; Venus - white box    ; Earth - turquoise box
Mars - red box    ; Jupiter - orange box    ; Saturn - yellow box
Uranus - green box    ; Neptune - blue box    ; Pluto - purple box

Notice that if you move your mouse cursor over any object in this image, relevant data for that object
appears in the black display box at the bottom of the frame.

- The 'Orbits' tab shows the planetary positions (Mercury thru Saturn) at the date/time selected as viewed
from above the Solar System. The 'Map' tab shows Earth and illustrates which parts are experiencing
daylight and which are experiencing night. The 'Calendar' tab shows a calendar for the current month and
marks the four major lunar phases (new, first, full, last) with the white part being that which we see. The
calendar can also be changed to others months if needed using the 'Options' menu to the right.

Experiment with this applet it to see how astronomers use computers and software to help them identify
and get basic information about common celestial objects and how to quickly locate them on the sky.

4.17.   Make sure the settings are correct for Miami and the class date you are scheduled to do this lab.
Press the 'Now' button in the upper lefthand corner of the applet. Make sure you are viewing the 'Sky'
tab image frame and turn on the 'Ecliptic', 'Celestial equator', and 'Constellations' options. Under the
'Show Names...' menu, select 'Constellations' as well.

a) (1 pt) Which Solar System objects (planets, Moon, Sun) are observable (if any)?



b) (1 pt) What do you notice about the positions/path of all the objects you listed in #4.15a ?



c) (1 pt) Move your cursor over one of the Solar System objects. What 8 items of data can you
determine about objects with this program?

4.18. Again, make sure the settings are correct for Miami, the date this lab is scheduled for, and the
start time of your class. Reset the date/time settings if you need. Then select the 'Calendar' tab.

a) (1 pt) What is the date and time of the full moon for this month?


b) (1 pt) What is the date and time of the new moon for this month?


c) (1 pt) Using the 'Options' pull-down menu, find the rise and set times for the Moon on your
scheduled class date.

4.19.   Finally, select the 'Tables' tab. A blank screen and menu bars should appear.

a) (1 pt) List the four MAJOR (excluding 'Galilean moons') types of tables that can be created by this applet.



b) (1 pt) Generate a table of today's ephemeris for all planets. When the table is generated and on screen,
print out a copy of this by pressing 'Print' in your browser. Be sure to turn in this page with the rest of
your lab activities.

4.20. (2 pts) List two advantages and two problems with using star charts and software like "Sky View Café".

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