Astronomy Rough Notes – Star Gaze
BRING:
Handouts
Flashlight with red filter (one cellophane)
Star wheel
Magazines
Earth Globe
Orrery
Curtain
STOP sign
DISCLAIMER: These notes do NOT cover everything you need to know. You may need to look up some
item or concept online or in a text. Test questions are not exact copies of the OBJECTIVES but if you
know the OBJECTIVES thoroughly, you should do well on the exams.
HANDOUTS:
Star Charts - For the most recent star chart, I use www.Skymaps.com
To print a star chart for different dates, times and locations, try www.Heavens-above.com
Another good star chart can be found at www.skyandtelescope.com
NOT HANDED OUT IN CLASS BUT NEEDED:
Observing Projects: Sunset Assignment
FALL SEMESTER STUDENTS USE THIS LINK: Sunset Observation – FALL SEMESTER
SPRING SEMESTER STUDENTS USE THIS LINK: Sunset Observation – SPRING SEMESTER
Observing Projects: Star Gazing assignment
Observing Projects: Telescope assignment
OBJECTIVES:
Identify and use the correct color light to maintain dark adaptation when stargazing.
Observe and record the position of the sun at sunset.
*Describe positions of stars, Moon, Sun on the sky using direction and altitude.
*Measure altitudes using the fist method.
Define and use horizon and zenith.
Correctly hold and orient a star chart and use it to find stars and constellations.
Practice star hopping to locate stars and constellations.
*Explain why the date and time are included on star charts
State the magnitude scale for stars. Given a star’s magnitude, identify if it is bright or faint.
Identify the first four Greek letters. For what do astronomers use them?
Define rotation and revolution as used by astronomers. Use them correctly when describing the motion of
Earth, other planets, Sun and Moon.
CLASSROOM:
Dark adaptation
Exercise with bright/dim lights
When star gazing, eye pupil needs to open up (~15 minutes)
It shuts down quickly in response to white light but not to red light.
Show prepared flashlight
For star gazing, cover the lens with red plastic or red cellophane.
Describing positions on the sky (Give direction and altitude)
Direction – Find N, S, E, W as described in class
Altitude Use horizon and zenith
Use elevation
About 45 degrees (half way between zenith and horizon)
Extended fist is about 10 degrees across knuckles
Use extended fist to measure “heights” above horizon (Use eye level as the horizon.)
Use extended fist to measure the angle between two objects
Exercise (Right angle in classroom)
Exercise (Height of building from lobby)
Ex: Moon is toward the SE and 30o above the horizon.
Ex: I saw a bright object in the North about 60o above the horizon.
Ex: Around August 15 at 10 pm, Vega will be located near the zenith.
Review Sunset assignment
Review Star Gazing assignment
Review Telescope assignment
Star Charts
Find N, S, E, W
Orient the star chart –
Face one direction, e.g. west.
Put west horizon of star chart toward your belly.
West portion of star chart matches west portion of sky.
Zenith, horizon and in between (Angles)
Zenith at 90 degrees, horizon at 0 degrees
Note where constellation is on map (direction and altitude)
Find it on the sky.
Star hopping – Use one constellation to find others.
Ex: Ursa Major, Big Dipper
Pointer stars to Polaris (hence north)
On to Cassiopeia, to Andromeda
Different cultures, Drinking Gourd
Ex: Orion
Belt to Sirius
Belt to Aldebaran (Taurus) and Pleiades
Greek alphabet
Alpha ( α ), beta ( β ), gamma (γ ), delta ( δ )
Brightest stars in that constellation
Why the Date and Time are on the star chart – Earth’s rotation and revolution
Time because Earth rotates
(Make sure you can explain this to someone else in more detail!)
Date because Earth revolves around Sun
(Again make sure you can explain this to someone else in more detail!)
Demo in class. Also see text or web
Magnitude scale
Hipparchus
6 faint  1 bright
Now extended to negative numbers (Ex. Sirius, brightest star in the sky, has magnitude -1.4)
Resources for star gazing
See “Star Gazing assignment” above.
HOMEWORK:
Begin working the sunset assignment. Turn it in on or before the due date.
Check the calendar for star gazing and telescope opportunities.
Plan when you will go star gazing and how you will get there.
Review these notes.
Make a flash card for each objective.
Form study groups, compare notes.
Revised 3 January 2016