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SN 2003gd
SN 2003gd was a Type II-P supernova explosion in the spiral galaxy Messier 74, located in the constellation Pisces. SN 2003gd was discovered on 12 June 2003 by Robert Evans, using a 0.31m reflector, and its discovery was confirmed on 13 June 2003 by R. H. McNaught using the 1.0m telescope at the Siding Spring Observatory. This supernova was located along the outer edge of a spiral arm, from the galactic nucleus at an angular offset east and south of the core. It was discovered at the end of its "plateau phase", approximately 86 days after its estimated explosion date of 18 March 2003. Despite a lower tail luminosity in the light curve, this appears to be a normal Type II-p. A light echo from nearby dust was detected in archival images from 2004. Messier 74 had been observed approximately 200 days before the explosion with the Hubble Space Telescope, and about 300 days before using the Gemini Telescope. Astronomers were able to identify an object in these pre-supernova images th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spitzer Space Telescope
The Spitzer Space Telescope, formerly the Space Infrared Telescope Facility (SIRTF), was an infrared space telescope launched in 2003. Operations ended on 30 January 2020. Spitzer was the third space telescope dedicated to infrared astronomy, following IRAS (1983) and ISO (1995–1998). It was the first spacecraft to use an Earth-trailing orbit, later used by the Kepler planet-finder. The planned mission period was to be 2.5 years with a pre-launch expectation that the mission could extend to five or slightly more years until the onboard liquid helium supply was exhausted. This occurred on 15 May 2009. Without liquid helium to cool the telescope to the very low temperatures needed to operate, most of the instruments were no longer usable. However, the two shortest-wavelength modules of the IRAC camera continued to operate with the same sensitivity as before the helium was exhausted, and continued to be used into early 2020 in the Spitzer Warm Mission. During the warm mission, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Curve
In astronomy, a light curve is a graph of light intensity of a celestial object or region as a function of time, typically with the magnitude of light received on the y axis and with time on the x axis. The light is usually in a particular frequency interval or band. Light curves can be periodic, as in the case of eclipsing binaries, Cepheid variables, other periodic variables, and transiting extrasolar planets, or aperiodic, like the light curve of a nova, a cataclysmic variable star, a supernova or a microlensing event or binary as observed during occultation events. The study of the light curve, together with other observations, can yield considerable information about the physical process that produces it or constrain the physical theories about it. Variable stars Graphs of the apparent magnitude of a variable star over time are commonly used to visualise and analyse their behaviour. Although the categorisation of variable star types is increasingly done from their s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernovae
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. Supernovae are more energetic than novae. In Latin, ''nova'' means "new", referring astronomically to what appears to be a temporary new bright star. Adding the prefix "super-" distinguishes supernovae from ordinary novae, which are far less luminous. The word ''supernova'' was coined by Walter Baade and Fritz Zwicky in 1929. The last supernova to be directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Evolution
Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are formed from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star. Nuclear fusion powers a star for most of its existence. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing throug ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Supergiant
Red supergiants (RSGs) are stars with a supergiant luminosity class ( Yerkes class I) of spectral type K or M. They are the largest stars in the universe in terms of volume, although they are not the most massive or luminous. Betelgeuse and Antares are the brightest and best known red supergiants (RSGs), indeed the only first magnitude red supergiant stars. Classification Stars are classified as supergiants on the basis of their spectral luminosity class. This system uses certain diagnostic spectral lines to estimate the surface gravity of a star, hence determining its size relative to its mass. Larger stars are more luminous at a given temperature and can now be grouped into bands of differing luminosity. The luminosity differences between stars are most apparent at low temperatures, where giant stars are much brighter than main-sequence stars. Supergiants have the lowest surface gravities and hence are the largest and brightest at a particular temperature. The ''Yerkes'' o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemini Observatory
The Gemini Observatory is an astronomical observatory consisting of two 8.1-metre (26.6 ft) telescopes, Gemini North and Gemini South, which are located at two separate sites in Hawaii and Chile, respectively. The twin Gemini telescopes provide almost complete coverage of both the northern and southern skies. They are currently among the largest and most advanced optical/infrared telescopes available to astronomers. ''(See List of largest optical reflecting telescopes)''. The National Science Foundation (NSF) of the United States, the National Research Council of Canada, CONICYT of Chile, MCTI of Brazil, and MCTIP of Argentina own and operate the Gemini Observatory. The NSF is currently (2017) the majority partner, contributing approximately 70% of the funding needed to operate and maintain both telescopes. The operations and maintenance of the observatory is managed by the Association of Universities for Research in Astronomy (AURA), through a cooperative agreement with NSF. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories. The Space Telescope Science Institute (STScI) selects Hubble's targets and processes the resulting data, while the Goddard Space Flight Center (GSFC) controls the spacecraft. Hubble features a mirror, and its five main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detaile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Echo
309x309px, Reflected light following path B arrives shortly after the direct flash following path A but before light following path C. B and C have the same apparent distance from the star as seen from Earth.">Earth.html" ;"title="apparent distance from the star as seen from Earth">apparent distance from the star as seen from Earth. A light echo is a physical phenomenon caused by light reflection (physics), reflected off surfaces distant from the source, and arriving at the observer with a delay relative to this distance. The phenomenon is analogous to an echo (phenomenon), echo of sound, but due to the much faster speed of light, it mostly only manifests itself over astronomical distances. For example, a light echo is produced when a sudden flash from a nova is reflected off a cosmic dust cloud, and arrives at the viewer after a longer duration than it otherwise would have taken with a direct path. Because of their geometries, light echoes can produce the illusion of superlumin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiral Arm
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''Alt URL pp. 124–151) and, as such, form part of the . Most spiral galaxies consist of a flat, rotating containing s, gas and dust, and a central concentration of stars known as the |
Pisces (constellation)
Pisces is a constellation of the zodiac. Its vast bulk – and main asterism viewed in most European cultures per Greco-Roman antiquity as a distant pair of fishes connected by one cord each that join at an apex – are in the Northern celestial hemisphere. Its old astronomical symbol is (♓︎). Its name is Latin for "fishes". It is between Aquarius, of similar size, to the southwest and Aries, which is smaller, to the east. The ecliptic and the celestial equator intersect within this constellation and in Virgo. This means the sun passes directly overhead of the equator, on average, at approximately this point in the sky, at the March equinox. Features The March equinox is currently located in Pisces, due south of ω Psc, and, due to precession, slowly drifting due west, just below the western fish towards Aquarius. Stars * Alrescha ("the cord"), otherwise Alpha Piscium (α Psc), 309.8 lightyears, class A2, magnitude 3.62. Variable binary star. * Fumalsamakah ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siding Spring Observatory
Siding Spring Observatory near Coonabarabran, New South Wales, Australia, part of the Research School of Astronomy & Astrophysics (RSAA) at the Australian National University (ANU), incorporates the Anglo-Australian Telescope along with a collection of other telescopes owned by the Australian National University, the University of New South Wales, and other institutions. The observatory is situated above sea level in the Warrumbungle National Park on Mount Woorat, also known as Siding Spring Mountain. Siding Spring Observatory is owned by the Australian National University (ANU) and is part of the Mount Stromlo and Siding Spring Observatories research school. More than 100 million worth of research equipment is located at the observatory. There are over 60 telescopes on site, though not all are operational. History The original Mount Stromlo Observatory was set up by the Commonwealth Government in 1924. After duty supplying optical components to the military in World W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reflecting Telescope
A reflecting telescope (also called a reflector) is a telescope that uses a single or a combination of curved mirrors that reflect light and form an image. The reflecting telescope was invented in the 17th century by Isaac Newton as an alternative to the refracting telescope which, at that time, was a design that suffered from severe chromatic aberration. Although reflecting telescopes produce other types of optical aberrations, it is a design that allows for very large diameter objectives. Almost all of the major telescopes used in astronomy research are reflectors. Many variant forms are in use and some employ extra optical elements to improve image quality or place the image in a mechanically advantageous position. Since reflecting telescopes use mirrors, the design is sometimes referred to as a catoptrics, catoptric telescope. From the time of Newton to the 1800s, the mirror itself was made of metal usually speculum metal. This type included Newton's first designs and eve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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