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What is used to measure the angle of the North Star?
Use the sight line on the top of the aiming beam to align the beam with the North Star. Use the protractor to measure the angle between the beam and the horizon (which is 90° to the plumb line). This angle is your latitude.
How do you find the altitude of a star?
Formula for altitude of star
- alt = angle of altitude of star.
- lat = latitude of observer.
- d = declination of star.
- H = hour angle of star = (t – RA)(360/24)
- RA = right ascension of star.
- t = local sidereal time.
- RA and t are measured on a scale from 0 to 24; the formula above converts the angle H to degrees (0 to 360 scale)
What instrument is used to get the altitude of Polaris?
The mariner’s astrolabe was a brass ring used to observe the altitude of the North Star or the sun.
Is there a North Star in Australia?
The gravitational pulls of the Sun and Moon cause Earth’s axis to precess slowly. At that time, Polaris will be visible anywhere north of 45.95° south latitude (90°–44.62°+0.57°), and our current “North Star” will grace the skies above all of Africa and Australia.
What is the maximum altitude of a star?
90 degrees
A star on the horizon has an altitude of 0 degrees. A star straight overhead has the maximum altitude of 90 degrees.
How are the Stars used to determine latitude?
Determining Latitude. To find your latitude using the stars, you only need to find the North Star, called Polaris. The North Star is a star that is directly above the North Pole and appears not to be moving during the night. If you were standing at the North Pole, the North Star would be directly above you.
How is the altitude of a star measured?
The altitude of a star is the measurement in degrees of the angle of the star above the horizon. Flat out on the horizon is 0° and straight up in the sky is at 90°, which has a special name, the zenith. Thank you for your input. Go outside on a dark, clear, starry night.
How many degrees above the horizon is the North Star?
Using the North Star as a guide. From New York it stands 41 degrees above the northern horizon, which also corresponds to the latitude of New York. Since 10 degrees is roughly equal to your clenched fist held at arm’s length, from New York Polaris would appear to stand about “four fists” above the northern horizon.
How is the latitude of the North Pole determined?
Determining Latitude. If you measure the angle of the North Star above the horizon, that will be the same as your latitude. Think about it: the North Pole is a latitude of 90 degrees north, and the equator is 0 degrees north. At the North Pole, the North Star is above, which is 90 degrees above the horizon.