Professional astronomy is split into observational and theoretical branches. Observational astronomy is focused on acquiring data from observations of astronomical objects. This data 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. These two fields complement each other. Theoretical astronomy seeks to explain observational results and observations are used to confirm theoretical results.
Astronomy is one of the few sciences in which amateurs play an active role. This is especially true for the discovery and observation of transient events. Amateur astronomers have helped with many important discoveries, such as finding new comets. (Full article...)
Image 7Places like Paranal Observatory offer crystal clear skies for observing astronomical objects with or without instruments. (from Amateur astronomy)
Image 8Amateur astronomer recording observations of the sun. (from Amateur astronomy)
Image 9Artist conception of the Big Bang cosmological model, the most widely accepted out of all in physical cosmology (neither time nor size to scale) (from Physical cosmology)
Image 14An image of the Cat's Paw Nebula created combining the work of professional and amateur astronomers. The image is the combination of the 2.2-metre MPG/ESO telescope of the La Silla Observatory in Chile and a 0.4-meter amateur telescope. (from Amateur astronomy)
Image 19Segment of the astronomical ceiling of Senenmut's Tomb (circa 1479–1458 BC), depicting constellations, protective deities, and twenty-four segmented wheels for the hours of the day and the months of the year (from History of astronomy)
Image 30Comparison of CMB (Cosmic microwave background) results from satellites COBE, WMAP and Planck documenting a progress in 1989–2013 (from History of astronomy)
Image 32ALMA is the world's most powerful telescope for studying the Universe at submillimeter and millimeter wavelengths. (from Observational astronomy)
Image 33Portrait of the Flemish astronomer Ferdinand Verbiest who became Head of the Mathematical Board and Director of the Observatory of the Chinese emperor in 1669 (from Astronomer)
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Artist's illustration showing the life of a massive star as nuclear fusion converts lighter elements into heavier ones. When fusion no longer generates enough pressure to counteract gravity, the star rapidly collapses to form a black hole. Theoretically, energy may be released during the collapse along the axis of rotation to form a GRB.
In gamma-ray astronomy, gamma-ray bursts (GRBs) are immensely energetic explosions that have been observed in distant galaxies, being the brightest and most extreme explosive events in the entire universe, as NASA describes the bursts as the "most powerful class of explosions in the universe". They are the most energetic and luminous electromagnetic events since the Big Bang. Gamma-ray bursts can last from ten milliseconds to several hours. After the initial flash of gamma rays, an "afterglow" is emitted, which is longer lived and usually emitted at longer wavelengths (X-ray, ultraviolet, optical, infrared, microwave and radio).
... that the Antlia Dwarf galaxy may have distorted the shape of its neighbour NGC 3109 one billion years ago?
... that AP Columbae, the closest young star known, formed after the dinosaurs became extinct?
... that a planet was discovered around the star MOA-2009-BLG-387L after it eclipsed a background star, refracting the star's light in a process called gravitational microlensing?
The Musket Ball Cluster (DLSCL J0916.2+2951) is a galaxy cluster that exhibits separation between its baryonic matter and dark matter components. The cluster is a recent merger of two galaxy clusters in Cancer constellation. This composite image shows the Chandra (red) and Hubble (yellow and white) observation data.
4 August 2007 – The Phoenix Mars Lander is launched from Cape Canaveral, carrying science instruments to analyze soil samples of the Martian northern polar region
21 August 2017 – NASA.gov conducts a broadcast of the total solar eclipse with more than 50 million views of the live broadcast, and almost 31 million unique views on Facebook before and after the eclipse