Lecture #2
True
In the southern hemisphere, it is difficult, but not impossible, to find the location of the south celestial pole. (T/F)
From East to West
What direction do stars move?
Counterclockwise direction
What direction do the stars circle the poles in the northern hemisphere?
From West to East
What direction does the Earth rotate?
Ante-meridian
What does AM stand for?
Post-meridian
What does PM stand for?
Stars that circle the poles.
What does circumpolar mean?
Daily
What does diurnal mean?
Circles around the North Star
What does it mean when a star is circumpolar?
Celestial Coordinates
What does the celestial sphere have a system of?
60 arcseconds
What is 1 arcminute?
Size of a US quarter as seen from 5 km (3 miles) or a penny as seen from 2.2 miles.
What is 1 arcsecond the same as?...
60 arcminutes OR 3,600 arcseconds
What is 1 degree? (SEE SLIDE 10 on lecture 2 powerpoint)
The North Star
What is Polaris also known as?
Meridian
What is a line from due north to due south that passes straight overhead called?
All light reflects the same, but not all light refracts the same.
What is a rule about light dealing with reflection and refracting?
The north-south position of a star on the celestial sphere. Declination is measured in degrees, arcminutes, and arcseconds. The celestial equator is defined to have a declination of zero degrees.
What is declination?
Zenith
What is located straight up?
The east-west coordinates of an object on the celestial sphere. R.A. is measured in hours, minutes, and seconds of time. The vernal equinox is defined to be zero degrees.
What is right ascension?
The core is as hot as the sun, and as big as the moon.
What is soooooo special about Earth's core?
Venus
What is the 3rd brightest star in the night sky?
Vega Star
What is the 5th brightest star in the sky?
Polaris
What is the North Star called?
Azimuth
What is the direction to the star as measured from true north called?
Celestial Equator
What is the equator of the Earth projected onto the celestial sphere?
Altitude
What is the height of a star above the horizon called?
Where the dome meets the Earth?
What is the horizon?
North Celestial Pole
What is the point directly over the Earth's true north pole?
South Celestial Pole
What is the point directly over the Earth's true south pole?
The point directly over head.
What is the zenith?
The magnetic north pole is NOT located in the same place as the true North Pole
What is true about the magnetic north and the North Pole?
1 degree across
What is your finger held at arms length?
10 degrees
What is your fist at arms length?
20 degrees across
What is your outstretched hand at arms length?
Altitude & Azimuth
What part of a star changes during the course of night as the star rises and sets?
At due east and due west
Where does the celestial equator meet the horizon?
The Royal Observatory in Greenwich, England
Where is 0 degrees located?
-longitude: 78 degrees 52'08.4" West -latitude: 38 degrees 26' 56.4" N
Where is Harrisonburg, VA located?
Near the North Celestial Pole, but not exactly was the pole. It is currentlty 1 degree away from the pole.
Where is Polaris?
90 degrees North
Where is the North Pole?
Greenwich, England at the Royal Observatory
Where is the Prime Meridian located?
90 degrees South
Where is the South Pole?
Canada
Where is the magnetic pole currently located?
longitude
Your east-west position on Earth.
latitude
Your north-south position on Earth.
Using degrees, minutes of arcminutes, and arcseconds
How are angles measured in atronomy?
Drop straight down from the North Celestial Pole to the horizon
How do you find due north?
1/2 degree in size
How many degrees are the Sun and Moon each?
Every 200,000 years
How often does the magnetic field switch?
As a great dome over our heads.
How should we think of the sky?
0 degrees
The equator has a latitude of_______?
