An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either observational or theoretical astronomy. Examples of topics or fields astronomers study include planetary science, solar astronomy, the origin or evolution of stars, or the formation of galaxies. A related but distinct subject is physical cosmology, which studies the Universe as a whole.
Amateur astronomy is a hobby where participants enjoy observing or imaging celestial objects in the sky using the unaided eye, binoculars, or telescopes. Even though scientific research may not be their primary goal, some amateur astronomers make contributions in doing citizen science, such as by monitoring variable stars, double stars, sunspots, or occultations of stars by the Moon or asteroids, or by discovering transient astronomical events, such as comets, galactic novae or supernovae in other galaxies.
Astrophotography, also known as astronomical imaging, is the photography or imaging of astronomical objects, celestial events, or areas of the night sky. The first photograph of an astronomical object was taken in 1840, but it was not until the late 19th century that advances in technology allowed for detailed stellar photography. Besides being able to record the details of extended objects such as the Moon, Sun, and planets, modern astrophotography has the ability to image objects invisible to the human eye such as dim stars, nebulae, and galaxies. This is done by long time exposure since both film and digital cameras can accumulate and sum photons over these long periods of time.
Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying, light-collecting optical instrument, such as a telescope or microscope, or eye protection. Vision corrected to normal acuity using corrective lenses is still considered "naked".
A star party is a gathering of amateur astronomers for the purpose of observing objects and events in the sky. Local star parties may be one-night affairs, but larger events can last up to a week or longer and attract hundreds or even thousands of participants. Many clubs have monthly star parties during the warmer months. Large regional star parties are held annually and are an important part of the hobby of amateur astronomy. A naturally dark site away from light pollution is typical.
A Dobsonian telescope is an altazimuth-mounted Newtonian telescope design popularized by John Dobson in 1965 and credited with vastly increasing the size of telescopes available to amateur astronomers. Dobson's telescopes featured a simplified mechanical design that was easy to manufacture from readily available components to create a large, portable, low-cost telescope. The design is optimized for observing faint, deep-sky objects such as nebulae and galaxies. This type of observation requires a large objective diameter of relatively short focal length and portability for travel to less light-polluted locations.
Observational astronomy is a division of astronomy that is concerned with recording data about the observable universe, in contrast with theoretical astronomy, which is mainly concerned with calculating the measurable implications of physical models. It is the practice and study of observing celestial objects with the use of telescopes and other astronomical instruments.
A deep-sky object (DSO) is any astronomical object that is not an individual star or Solar System object. The classification is used for the most part by amateur astronomers to denote visually observed faint naked eye and telescopic objects such as star clusters, nebulae and galaxies. This distinction is practical and technical, implying a variety of instruments and techniques appropriate to observation, and does not distinguish the nature of the object itself.
The term night sky, usually associated with astronomy from Earth, refers to the nighttime appearance of celestial objects like stars, planets, and the Moon, which are visible in a clear sky between sunset and sunrise, when the Sun is below the horizon.
The RTMC Astronomy Expo was one of the major gatherings of amateur astronomers in the United States.
The Texas Star Party (TSP) is a large annual star party in the United States.
Astronomy is a monthly American magazine about astronomy. Targeting amateur astronomers, it contains columns on sky viewing, reader-submitted astrophotographs, and articles on astronomy and astrophysics for general readers.
Visible-light astronomy encompasses a wide variety of observations via telescopes that are sensitive in the range of visible light. Visible-light astronomy is part of optical astronomy, and differs from astronomies based on invisible types of light in the electromagnetic radiation spectrum, such as radio waves, infrared waves, ultraviolet waves, X-ray waves and gamma-ray waves. Visible light ranges from 380 to 750 nanometers in wavelength.
The Royal Astronomical Society of Canada (RASC) is a national, non-profit, charitable organization devoted to the advancement of astronomy and related sciences. At present, there are 28 local branches of the Society, called Centres, in towns and cities across the country from St. John's, Newfoundland, to Victoria, British Columbia, and as far north as Whitehorse, Yukon. There are about 5100 members from coast to coast to coast, and internationally. The membership is composed primarily of amateur astronomers and also includes numerous professional astronomers and astronomy educators. The RASC is the Canadian equivalent of the British Astronomical Association.
The International Year of Astronomy (IYA2009) was a year-long celebration of astronomy that took place in 2009 to coincide with the 400th anniversary of the first recorded astronomical observations with a telescope by Galileo Galilei and the publication of Johannes Kepler's Astronomia nova in the 17th century. The Year was declared by the 62nd General Assembly of the United Nations. A global scheme, laid out by the International Astronomical Union (IAU), was also endorsed by UNESCO, the UN body responsible for educational, scientific, and cultural matters.
Astronomy Now is a monthly British magazine on astronomy and space. According to the Royal Astronomical Society, Astronomy Now is the "principal amateur astronomy magazine in Britain" with a reputed circulation of 24,000.
The Escambia Amateur Astronomers Association (EAAA) is an amateur astronomy club in Northwest Florida.
L. L. "Stub" Stewart Memorial State Park is a 1,654-acre (669 ha) Oregon state park in Washington County near the community of Buxton. When the park opened in 2007 it was the first new full-service state park in Oregon since 1972. The park includes hiking trails, mountain bike trails, horseback riding, RV and tent campsites, and cabins among other amenities. Located off Oregon Route 47 in the foothills of the Northern Oregon Coast Range, the park connects to the Banks–Vernonia State Trail.
The Astronomical Society of Victoria (ASV) is an amateur astronomy club in the state of Victoria, Australia. It was founded in 1922, making it one of the oldest such clubs in the country, and with some 1500 members it claims to be one of the largest amateur astronomy organisations in the southern hemisphere. Membership is open to all with an interest in astronomy, and the society caters for people with a wide range of ages, backgrounds, abilities and interests.
The Astronomy Centre, also known as the Amateur Astronomy Centre, is an astronomical observatory located in northern England which is run by experienced amateur astronomers and is open to the public at certain times.
