What latitude is based upon?

Latitude horizon
• Altitude: Angular distance above the horizon

ZENITH
ZENITH – DIRECTLY OVERHEAD

Polaris
• Polaris – NORTH STAR,
Earth’s axis points to Polaris,
POSITION of Polaris STAYS THE SAME

HOW TO FIND
POLARIS?
POLARIS
Big Dipper
Little Dipper

Finding Polaris

• http://ecuip.lib.uchicago.edu/diglib/science/ cultural_astronomy/interactives/polaris/pol aris.swf

• http://www.astropix.com/HTML/C_SPRING
/URSAS.HTM

Observer Altitude of
Polaris
1
90 o
Latitude
90 o N
2 65 o
65 o N
3 35 o
4 0 o
35 o N
0 o

Polaris
• Polaris – is at Zenith at the North Pole and has an altitude of 90 o
Polaris is 430 light years away (or approximately 6 trillion miles)

What is this person’s latitude?
Latitude = 43 o N

0 o
30 o N
90 o N

• http://www.onr.navy.mil/focus/spacescienc es/skyobserve/constellations4.htm

Altitude of Polaris equals
in the Northern
Hemisphere

SOUTHERN HEMISPHERE
Very faint star

Southern Cross

Southern
Cross

• In your notes,
• For each location, determine the altitude of
Polaris.