Portal:Astronomy
Astronomy portal
Astronomy (from Greek: ἀστρονομία) is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets; the phenomena also includes supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, all phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject is physical cosmology, which is the study of the Universe as a whole.
Astronomy is one of the oldest of the natural sciences. The early civilizations in recorded history, such as the Babylonians, Greeks, Indians, Egyptians, Nubians, Iranians, Chinese, Maya, and many ancient indigenous peoples of the Americas, performed methodical observations of the night sky. Historically, astronomy has included disciplines as diverse as astrometry, celestial navigation, observational astronomy, and the making of calendars, but professional astronomy is now often considered to be synonymous with astrophysics.
Professional astronomy is split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects, which is then analyzed using basic principles of physics. Theoretical astronomy is oriented toward the development of computer or analytical models to describe astronomical objects and phenomena. The two fields complement each other, with theoretical astronomy seeking to explain observational results and observations being used to confirm theoretical results.
Astronomy is one of the few sciences in which amateurs still play an active role, especially in the discovery and observation of transient events. Amateur astronomers have made and contributed to many important astronomical discoveries, such as finding new comets.
Selected article
.jpg)
Triton is one of the few moons in the Solar System known to be geologically active. As a consequence, its surface is relatively young, with a complex geological history revealed in intricate and mysterious cryovolcanic and tectonic terrains. Part of its crust is dotted with geysers believed to erupt nitrogen.
The moon was discovered by British astronomer William Lassell just 17 days after Neptune itself was discovered by German astronomers Johann Gottfried Galle and Heinrich Louis d'Arrest, who were following co-ordinates given them by French astronomer and mathematician Urbain Le Verrier.
Did you know...
- ... that Caroline Moore was 14 years old when she discovered supernova 2008ha?
- ... that although Charles Messier discovered the galaxy M91 in 1781, it was added to his catalogue only two centuries later?
- ... that Beta Cassiopeiae is the brightest of the Delta Scuti variables in the sky?
- ... that the fall of the Neuschwanstein meteorite in 2002 was observed by the European Fireball Network and outdoor witnesses through most of Central Europe?
- ... that AG Pegasi has been described as the slowest nova ever recorded?
Subcategories
- Select [►] to view subcategories
Projects
Selected image
Mimas is a moon of Saturn. It was discovered in 1789 by William Herschel, after whom the large crater in the image is named. It is the twentieth-largest moon in the Solar System, and the smallest astronomical body that is known to be rounded in shape because of self-gravitation. This photograph of Mimas was taken by the unmanned spacecraft Cassini in 2010.
April anniversaries
- 3 April 2014 – NASA announces that the Cassini orbiter has found evidence of an underground body of water on Enceladus, a moon of Saturn
- 12 April 1961 – Cosmonaut Yuri Gagarin becomes the first human to enter outer space when he is launched into orbital flight in Vostok 1
- 19 April 1971 – The first space station, Salyut 1, is launched into orbit
- 24 April 1990 – The Hubble Space Telescope, a powerful research tool and public relations boon for astronomy, is launched into orbit
Things you can do
|
Here are some Open Tasks :
Astronomy featured article candidates:
Astronomy articles for which peer review has been requested: |
Wikibooks
These books may be in various stages of development. See also the related Science and Mathematics bookshelves.
- Astronomy
- GAT: A Glossary of Astronomical Terms
- Introduction to Astrophysics
- General relativity
- Observing the Sky from 30°S
- Observing the Sky from 40°N
Wikijunior
Astronomical events
All times UT unless otherwise specified.
| 1 April, 00:21 | Moon at apogee |
| 5 April, 08:51 | New moon |
| 11 April, 19:42 | Mercury at greatest western elongation |
| 16 April, 22:13 | Moon at perigee |
| 19 April, 11:12 | Full moon |
| 22 April | Uranus at conjunction |
| 23 April, 02:00 | Lyrids peak |
| 25 April, 14:27 | Moon occults Saturn |
| 25 April, 19:49 | Moon occults Pluto |
| 28 April, 18:23 | Moon at apogee |
2019: January | February | March | April
2018: January | February | March | April | May | June | July | August | September | October | November | December
2017: January | February | March | April | May | June | July | August | September | October | November | December
2016: January | February | March | April | May | June | July | August | September | October | November | December
2015: January | February | March | April | May | June | July | August | September | October | November | December
2014: January | February | March | April | May | June | July | August | September | October | November | December
2013: January | February | March | April | May | June | July | August | September | October | November | December
2012: January | February | March | April | May | June | July | August | September | October | November | December
2011: January | February | March | April | May | June | July | August | September | October | November | December
2010: January | February | March | April | May | June | July | August | September | October | November | December
2009: January | February | March | April | May | June | July | August | September | October | November | December
2008: January | February | March | April | May | June | July | August | September | October | November | December
2007: January | February | March | April | May | June | July | August | September | October | November | December
2006: January | February | March | April | May | June | July | August | September | October | November | December
2005: May | June | July | August | September | October | November | December
Basics
Associated Wikimedia
- Shortcuts to this page: Astronomy portal • P:ASTRO