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Astronomy, which etymologically means " law of the stars," (from Greek: αστρονομία = άστρον + nomos) is a science involving the observation and explanation of events occurring outside Earth and its atmosphere. It studies the origins, evolution, physical and chemical properties of objects that can be observed in the sky (and are outside the earth), as well as the processes involving them...Lunar astronomy: the large crater is Daedalus, photographed by the crew of Apollo 11The Apollo 11 mission was the first manned lunar landing. It was the fifth manned mission in the Apollo program. That's one small step for [a] man, one giant leap for mankind. Neil Armstrong Crew Neil Armstrong (2), commander (and first to walk on the moo as they circled the MoonFor other moons in the solar system see natural satellite. For other uses see Moon (disambiguation). The Moon is the only natural satellite of Earth. It has no formal name other than "The Moon" although it is occasionally called Luna ( Latin for moon to d in 1969. Located near the center of the far sideThis article concerns the far side of the Moon. For other uses of the expression see Far side (disambiguation). The Far side of the Moon is the lunar hemisphere that is permanently turned away from the Earth. This face is not visible because the rotation of Earth's Moon, its diameter is about 93 kilometers (58 miles).
Astronomy is one of the few sciences where amateursAmateur astronomy often called back yard astronomy is a hobby whose participants enjoy observing celestial objects. It is usually associated with viewing the night sky when most celestial objects and events are visible, but sometimes amateur astronomers a can still play an active role, especially in the discovery and monitoring of transient phenomena. Astronomy is not to be confused with astrologyastrological chart (or horoscope) Y2K Chart This particular chart is calculated for January 1st, 2000 at 12:01:00 A. Eastern Standard Time in New York City, New York, USA. Longitude: 074W00'23" Latitude: 40N42'51") Astrology (from Greek: , astron "star" +, which assumes that people's destiny and human affairs in general are correlated to the apparent positions of astronomical objects in the sky -- although the two fields share a common origin, they are quite different; astronomers embrace the scientific methodThe scientific method is a sequence or collection of processes that are considered characteristic of scientific investigation and the acquisition of new scientific knowledge based upon physical evidence. Science deals with assertions about the way the wor, while astrologers do not.
1 Divisions of astronomy
In its earliest days, going back to ancient GreeceAncient Greece is the term used to describe the Greek-speaking world in ancient times. It refers not only to the territory of the present Greek state, but also to those areas settled in ancient times by Greeks: Cyprus, the Aegean coast of Turkey (then kno and other ancient civilizations, astronomy consisted largely of astrometry, measuring positions of stars and planets in the sky. Later, the work of Kepler and Newton paved the way for celestial mechanics, mathematically predicting the motions of celestial bodies interacting under gravity, and solar system objects in particular. Much of the effort in these two areas, once done largely by hand, is highly automated nowadays, to the extent that they are rarely considered as independent disciplines anymore. Motions and positions of objects are now easily known, and modern astronomy concerns itself much more with trying to observe and understand the actual physical nature of celestial objects—what makes them "tick".
Ever since the twentieth century the field of professional astronomy has tended to split into observational astronomy and theoretical astrophysics. Although most astronomers incorporate elements of both into their research, because of the different skills involved, most professional astronomers tend to specialize in one or the other. Observational astronomy is concerned mostly with getting data, which involves building and maintaining instruments and processing the resulting data; this branch is at times referred to as "astrometry" or simply as "astronomy." Theoretical astrophysics is concerned mainly with figuring out the observational implications of different models, and involves working with computer or analytic models.
The fields of study are also categorized in another two ways: by "subject", usually according to the region of space (e.g. Galactic astronomy) or "problems addressed" (such as star formation or cosmology); or by the way used for obtaining information.
