What is astronomy?
Astronomy is the science of celestial objects, the space, and the universe as a whole. Astronomy studies the sun and the moon, along with the stars, comets, galaxies, dust, planets, gas, and all other bodies or phenomena that is non-Earthly. Astronomy has been around since the ancient times. For example, in 200 B.C. the Babylonians are known to of documented the positions of many stars and predicted events that would take place on earth. Astronomy is used in physics, mathematics, and chemistry, to help explain the evolution, origin, and phenomena of the object. Astronomy is split into two categories: observational and theoretical. Observational astronomy is when data is acquired from observing astronomical objects. Theoretical astronomy is the development of the computer models that describe astronomical phenomena. One cannot be used without the other due to the fact that one confirms the results of the other. In the beginning, astronomy was used to help predict that objects that could be seen moving. These observations are how we came about having seasons, when the right time is to plant a certain crop and understand the year and why some are longer. That also has explained the motion of the planets along with the Sun and Moon. At that time the Sun and Moon we believed to rotate around the Earth. Astronomy was used to estimate the size and the distance of the Sun and Moon.
What kind of astronomers study stars?
A stellar astronomer is an astronomer who studies the sun and stars. Stellar astronomers study how stars get their light and what they are made of. Stars are used to help determine the distance in the universe. They study novas and supernovas which are stars that just suddenly brighten. One problem stellar astronomers have a hard time in this field is the distance from Earth to the closest star. Many astronomers have helped in the documentation of stars throughout history. A well-known Polish astronomer is Nicolas Copernicus the reason is he discovered that the Sun is the center of the universe instead of the Earth. An astronomer named Hipparchus documented 1020 stars and almost all the constellations in the northern hemisphere. The number of stars in the universe will always change. The naked eye is thought to be able to see about 6,000 stars on an average night. The northern hemisphere the number dramatically drops to 3,000. The reason this is because of no matter where you are you are never going to see the whole sky. Another well-known astronomer is Nicolas-Louis de Lacaille he documented 9,766 stars in just eleven months. He invented fourteen constellations that are still recognized today but are made from very faint stars. One that is still seen in the sky today is the Air Pump that he created around 1750. This constellation is now known as Pump. Although believed to be the same stars and constellations are very different. Stars are balls of plasma that lets off light because of nuclear fusion and its gravity holds it together. A constellation is a group of stars that have a certain region in the sky and create an image if created by a line. A star moves, unlike a constellation.
What are constellations?
Constellations are a group of stars that are in a pattern. They usually represent mythological gods or creatures, animals, or manufactured devices. Over 2500 years ago the Greeks identified the first constellation. Constellations vary from night to night due to the rotation of Earth allowing them to be used to help determine a season. Constellations have changed in size and shapes through the years and others have disappeared while others are only used by certain cultures. There are eighty-eight constellations that are named and most known. The largest constellation is Hydra; it is named after the multi-headed sea serpent that Hercules encounters. The most known constellation is called the Ursa Major which contains the Big Dipper. The constellations are separated into the southern and northern sky. The constellations in the northern sky are from Classic Greek legends. The southern constellations are modern inventions. Each constellation is different in size and shape. After the telescope astronomers have documented so that they can be used to navigate in the 14th to 16th century by sea travelers. Around the Milky Way is a dark cloud constellation that looks to be an emu. There are twelve constellations that are known as the zodiac signs that date back to prehistory. Although believed to be the same stars and constellations are very different. Stars are balls of plasma that lets off light because of nuclear fusion and its gravity holds it together. A constellation is a group of stars that have a certain region in the sky and create an image if created by a line. A star moves, unlike a constellation.
What is the relationship between constellations and the zodiac signs?
The zodiac signs are the constellations that mark the path the sun travels throughout the year. The zodiac signs use to align with the sun. For example, Aries is the zodiac sign for March 21 through April 19 which would mean the sun would appear in this sign through these dates. This has changed because of the way that we have determined the time, such as a year is 364 days and not 364.25 days. Also, the signs are not equal signs and shape. Most of the today’s constellations are more known to the Greek culture. Although we only use twelve zodiac signs there are actually thirteen signs that the sun travels through. The thirteen signs are:
The thirteenth sign is known as the Ophiuchus, or the Serpent Bearer, it sits between Sagittarius and Scorpius. The zodiac signs are great to help understand the orbits of the Sun, Earth, and Moon. The zodiac signs are all based on of Earth bound elements such as air (Gemini, Libra, and Aquarius), fire (Aries, Leo, and Sagittarius), water (Cancer, Scorpio, and Pisces), and earth (Taurus, Virgo, and Capricorn).