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Did you know that on a clear, dark night, you can count up to 4,000 separate stars without a telescope!? You are able to see stars that are billions and billions of miles away. The light given off by those stars have been traveling for thousands of years before they have even reached earth. Read on to learn how to find Constellations, how to use Star Charts, how to Find Directions in the Sky, and more.
Constellations came from the drawings of imaginary lines that connected bright stars by ancient stargazers. They name these drawings constellations and named the constellations after gods, people, animals and objects. These names were mostly based on Greek and Roman mythology.
But don't be looking for constellations that look like a recognizable person. Most constellations were named in honor of some mythical/legendary character. But getting to know the pictures of them and the legends behind them will make it easier for you to find the constellations and their main stars.
There are a total of 88 constellations. No one can see all of them at once. Some are in the southern skies and people in the northern hemisphere can't see these particular ones. And vice versa.
Also, the positions of the constellations change as the earth rovolves about the sun. The earth orbits the sun every 365.25 days and the constellations you can see during any month depend on the earth's position in relation to the sun. Because of this, the constellations appear to be moving through the sky throughout the year.
Some constellations can be see yearly. Most can be seen only during several months. Yet there is one month in which a constellation can be seen most readily. In this month, the constellation is either at its highest point or is shining most brightly. This is known as the culminating position.
Only about 30 constellations will be focused on this website. These are visible from nearly anywhere in the United States. Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpius, Sagittarius, Capricornus, Aquarius, Pisces, and Aries make up the Zodiac. The zodiac, which means "circle of animals," is an imaginary belt stretched across the sky throgh which the planets travel. The zodiac is divided into twelve equal sections; each section is named after the constellation found there.
Star charts are maps that plot the stars and constellations. They show the bright stars as though they were being projected on the inside of a giant, upside-down soup bowl. Each star chart shows only the stars that are visible in a single hemisphere. Because of earth's orbit, a star chart for May looks different from one for June, etc.
Not all stars in the charts are drawn the same. Mainly because the actual stars aren't the same. They are different in brightness. Stars' brightness depend on their size, surface temperature and distance from earth. The brightness of a star is called its magnitude. The brighter the stars is, the lower the magnitude is. For example, Sirius, the brightest star we can see, has a magnitude of -1.42. So, a star with a magnitude say, 6, is just barely visible with the unaided eye. In the charts, brighter stars(remember low magnitude) are denoted with an asterisk. The second brightes is a large dot. Fainter stars are small dots.
The star charts show you the shapes of the constellations and the brightness of the stars. To find them, you need to know your directions: north, south, east, west.
Firstly find north with a compass. If you don't have a compass, point your left shoulder to the setting sun late in the afternoon. The sun sets in the west. So, you'll being facing north, more or less.
The Big Dipper is made up of seven stars and looks like a cup with a long handle. The Big Dipper is well-known because it can be seen every clear night. Toward spring, look higher and to the northeast. During summer, it is still high and in the northwest sky. In fall, you can see it heading back to the lower part of the northern sky.
As the year goes by, the Big Dipper slowly changes its appearance. In the winter, the handle seems to be pointing down. Summertime finds the cup timming over. The position changes because the earth is constantly moving through its orbit.
The Big Dipper is an asterism, a group of stars that forms a shape in the sky. But it is not a constellation. The Big Dipper is part of a larger group of stars, Ursa Major (the Great Bear), which is a constellation.
Bright stars are given double names, the first part being a letter of the Greek alphabet, and the second the possessive name of the constellation to which it belongs. An example would be Alpha Centauri, the closest star to our Sun which is found in the constellation Centaurus. Generally the Alpha star of a constellation is the brightest, the Beta star the second brightest, etc. But this rule doesn't always apply because some of the stars were named inaccurately, some have changed in magnitude and some of the constellations have also been changed. Fainter stars may be given Roman letters or numbers.
Objects in the sky other than stars are given Messier (M) numbers, from the catalogue compiled by Messier in the 18th century or NGC numbers from the much more comprehensive New General Catalogue compiled in the 19th century.
Here are 10 constellations picked for you. If you need help, use the star charts.
- Aquila
- Lyra
- Ophiuchus
- Cassiopeia
- Perseus
- Pegasus
- Pisces
- Orion
- Auriga
- Eridanus
Spring Star Chart - Summer Star Chart - Fall Star Chart - Winter Star Chart
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STARGAZING
