The numbers for latitude go up to 90 degrees. 90 degrees north is near the North Pole, while 90 degrees south is in Antarctica. The Equator is equidistant between the 2 poles, and is 0 degrees. The numbers for longitude go from 0 to 180 degrees. They start at 0 at the Prime Meridian. The Prime Meridian is an arbitrary line that runs from the North to South pole through Europe and Africa.

It helps to imagine the celestial sphere as a giant bubble around Earth. There are globes that you can buy that map out major constellations and stars on a projection of the celestial sphere. Buy one to make it easier to reference to cross-check a star’s location!

In other words, declination is a celestial version of latitude, and right ascension is the celestial version of longitude! The celestial poles and Equator are an extension of the Earth’s Equator and poles. Like coordinates on Earth, the celestial coordinates are fixed positions. In other words, a specific star will always be located at the same coordinates, regardless of when you’re trying to find it. The symbol for right ascension looks like a cursive lower-case A. The symbol for declination looks like a lower-case O with a bar on top.

The arbitrary starting point for RA is the location of the sun on the first day of spring. The location of this line changes every year, and it is called the vernal equinox. Think of this as the Prime Meridian on a celestial sphere. Right ascension is always measured going east. Each hour means that 1/24th of the Earth has been traveled. This corresponds to 15 degrees along the equator.

The + or – sign at the beginning of the declination number tells you whether the star is in the northern or southern hemisphere. The plus sign means that the star is in the northern hemisphere, while the minus sign means that the star is in the southern hemisphere. A star that has a declination starting in 0 sits directly above the equator. For example, Polaris has a DEC of +89° 15′ 50. 8. ″ This means that Polaris is 89 degrees north of the equator.

For example, Detroit, Michigan is roughly 85° west. This translates roughly to 5h 30m right ascension. This means, that if a star has a declination between +15 and +75 and an RA between 8h 30m and 2h 30m, it may be visible on a given night from Detroit. Generally speaking, you can see stars within a 3-hour window in either direction. This is because each hour translates to 15°, and your maximum range in either direction is 45 degrees.

Star maps have a compass that will help you reorient them based on whether you’re facing north, south, east, or west. Buy a celestial globe to cross-reference star locations in 3D. Imagining where a star is in relation to where you live can be tough, but a celestial globe will make it easier. Celestial globes contain a projection of the stars with an actual globe underneath.

One example of a digital database is http://www. sky-map. org.

Binoculars are a great way to find stars if you don’t want to jump right into stargazing with a telescope.

This is why you often see amateur stargazers getting on their roof or balcony to do some stargazing! Even a slight change in elevation can help make stargazing easier.

There are dark parks where lights aren’t allowed that are designed specifically for stargazing. Look online to see if you live near one and consider visiting it if you want to give yourself the best possible chance of finding a star.

For example, if you’re using Polaris as a reference point, you know that it is at +89° DEC. If you’re looking for the Big Dipper, which starts at +61° DEC, then you can place two fists next to each other to find the approximate location of the Big Dipper. The way that this changes measurements depends upon the direction that you’re facing. If you’re looking north away from the equator, the right side of your hand will be 10° lower in terms of RA. If you’re facing south towards the equator, it will be 10° higher. The same is true for declination. You can convert RA to angles by converting every hour to 15°. This means that each fist you make translates to roughly 45 minutes of right ascension.

This is a particularly helpful trick when making minor adjustments to a telescope without a compass or equatorial mount.