|
| |
| | IK Pegasi(HR 8210) - Team 310 - Bulgaria |
 | | HR 8210 is a binary star with a normal star for a main component ( IK Pegasi A) and a hot white dwarf for a secondary component ( IK Pegasi B). | | | Also the merging of two white dwarfs assumes that the mass of the two merging dwarfs is lower than average, assuming a mass in their previous stages is even lower than the mass of the present A star. | | | The compact white dwarf, left after the red giant burst of IK Pegasi A, could not be affected by the blast of the older dwarf. |
|
http://eso.org/outreach/eduoff/edu-prog/catchastar/casreports-2004/rep-310
|
|
| |
| | Red dwarf stars within 10 parsecs |
| | At least 39 percent of the 250+ red dwarfs have been identified as flare and variable stars, and so are likely to be "young" enough to be rotating rapidly and generating a dynamic magnetic field. | | | Since this is older than the age of the universe (on the order of 10 billion years), these stars have yet to reach the white dwarf stage (University of Maryland definitions of a red dwarf and a white dwarf). | | | These flare stars are actually common because red dwarfs appear to make up more than two-thirds of all stars in our galaxy. |
|
http://www.solstation.com/stars/pc10rds.htm
|
|
| |
| | star (HyperDic hyper-dictionary) |
| | binary star, binary, double star; fixed star; giant star, giant; lodestar, loadstar; multiple star; neutron star; nova; red dwarf, red dwarf star; red giant, red giant star; sun; sun; supergiant; supernova; variable star, variable; white dwarf, white dwarf star | | | "The movie stars Dustin Hoffman as an autistic man" | | | Alpha Crucis; Beta Centauri; Beta Crucis; Deneb; Denebola; Pollux; Regulus; Spica; Sterope, Asterope |
|
http://www.hyperdic.net/dic/star.htm
|
|
| |
| | Red dwarf stars within 10 parsecs |
| | At least 39 percent of the 250+ red dwarfs have been identified as flare and variable stars, and so are likely to be "young" enough to be rotating rapidly and generating a dynamic magnetic field. | | | Since this is older than the age of the universe (on the order of 10 billion years), these stars have yet to reach the white dwarf stage (University of Maryland definitions of a red dwarf and a white dwarf). | | | At this point, it is no longer a main-sequence star (since it is no longer fusing hydrogen), but becomes a "white dwarf." The main sequence lifetime of a red dwarf is about 100 billion years, but some may last around a trillion years. |
|
http://www.solstation.com/stars/pc10rds.htm
|
|
| |
| | APOD Search Results for "Dwarf Star" |
| | The faint 9th magnitude red dwarf, currently 63 light-years away in the constellation Ophiucus, was recently discovered to be approaching our Solar System. | | | white dwarf stars in binary star systems are thought to draw enough mass from their companions to become unstable, triggering a nuclear detonation. | | | Trapezium is typical of young star clusters, then the survey results suggest that brown dwarfs and free-floating planets may be fairly common, but there are not enough to solve the mystery of dark matter in the Universe. |
|
http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search?Dwarf+Star
|
|
| |
| | red dwarf - Hutchinson encyclopedia article about red dwarf |
| | Two of the closest stars to the Sun, Proxima Centauri and Barnard's Star, are red dwarfs. | | | Red dwarfs burn slowly, and have estimated lifetimes of 100 billion years. | | | It concerns the plight of Dave Lister (Craig Charles), a 23rd-century reveller who, seeking to return home to Earth after a drinking binge, finds work on the spaceship Red Dwarf. |
|
http://encyclopedia.farlex.com/red+dwarf
(245 words)
|
|
| |
| | Known Space |
| | Ross 614: A double red dwarf (M4.5 and M?), 4.02 parsecs (13.1 light years) from us, and is not visible without a telescope. | | | Ross 154: This is a red dwarf (M4.5), 2.90 parsecs (9.3 light years) from us, and cannot be seen without a telescope. | | | Ross 128: A red dwarf (M5), 3.32 parsecs (11.1 light years) from us, and cannot be seen without a telescope. |
|
http://www.jimloy.com/astro/known.htm
(245 words)
|
|
| |
| | UV Ceti star |
| | UV Ceti itself is a faint M6eV dwarf that is part of a red dwarf binary system (the B component Luyten 726-8). | | | The flare activity is similar to that found on the Sun but appears comparatively more dramatic because of the normal faintness of red/ornage dwarfs. | | | Within seconds the star may brighten by up to 6 magnitudes, then decline, rapidly at first, then more gradually to a preflare level after several minutes or hours. |
|
http://www.daviddarling.info/encyclopedia/U/UV_Ceti_star.html
(245 words)
|
|
| |
| | Gemini, a February Constellation |
| | Both stars are spectroscopic binaries, and small telescopes show a 9th magnitude red dwarf companion, which is itself an eclipsing binary star. | | | (delta) Gem is a creamy-white star of magnitude 3.5 with a reddish magnitude 8.1 companion. | | | The primary star is a spectroscopic and occultation binary with a period of 8.17 years. |
|
http://www.faster.co.nz/~rasnz/Stars/Gemini.htm
(245 words)
|
|
| |
| | Constellation Mythology - Perseus the hero |
| | Castor is the alpha star and is made up of two blue-white spectroscopic double-stars and a red dwarf double, so Castor is actually a total of six stars, two of which can be seen by small telescopes! | | | Pollux, the beta star, is a magnitude 1.1 yellow giant, 10 times the size of our Sun, and is actually brighter than Castor, even though Castor, at magnitude 1.6, is listed as the alpha star. | | | Besides Castor, one of the best doubles in Gemini is Mu, containing a magnitude 2.9 star and a magnitude 9.8 companion. |
|
http://www.fvastro.org/articles/gemini.htm
(700 words)
|
|
| |
| | Capella 4 |
| | Capella D is a red dwarf star of spectral and luminosity type M4-5 V. It has about a tenth of Sol's mass, 25 to 30 percent of its diameter, and 0.05 percent of its luminosity. | | | For more information about stars including spectral and luminosity class codes, go to ChView's webpage on The Stars of the Milky Way. | | | (1931-93), this binary system was often designated as "Capella H" because the letters B through G were already used for faint field stars that are not gravitationally bound. |
|
http://www.solstation.com/stars2/capella4.htm
(1454 words)
|
|
| |
| | [sci.astro] Stars (Astronomy Frequently Asked Questions) (7/9) |
| | In the revised classification scheme, white dwarf designations still start with the letter D to indicate dwarf or "degenerate" stellar structure. | | | The coolest designation is open-ended; there is a star classified as DC13, for example, which is actually rather red, not white. | | | The upshot of all this is that we have "dwarf" stars of relatively high surface gravity, small radius, and low luminosity, and "giant" stars of low surface gravity, large radius, and high luminosity _and their spectra look different_. |
|
http://www.faqs.org/faqs/astronomy/faq/part7
(1454 words)
|
|
| |
| | The Brightest Red Dwarf by Ken Croswell |
| | Even though red dwarfs account for 80 percent of the galaxy's stars, no red dwarf is visible to the unaided eye. | | | It is also the brightest red dwarf (spectral class M) in the sky, with an apparent magnitude of 6.69, fainter than the conventional naked-eye threshold of 6.0. | | | Although red dwarfs outnumber all their brighter brethren put together, not a single one glows brightly enough to stir the unaided eye. |
|
http://www.kencroswell.com/thebrightestreddwarf.html
(1454 words)
|
|
| |
| | Gemini |
| | In fact, the entire system is comprised of six stars, including a red dwarf, Castor C, which slowly revolves around both Castor A and Castor B. This star is also a variable (and therefore catalogued as YY Gem). | | | This was the first binary system that was so recognised, in 1802 (or 1803, accounts vary) by William Herschel. | | | The star is a noted binary, discussed below. |
|
http://www.dibonsmith.com/gem_con.htm
(925 words)
|
|
| |
| | Citebase - Dwarf Cepheids in the Carina Dwarf Spheroidal Galaxy |
| | The thin red giant branch (RGB) of the Carina dwarf spheroidal galaxy appears at first sight quite puzzling and seemingly in contrast with the presence of several distinct bursts of star formation. | | | We have discovered 20 dwarf Cepheids (DC) in the Carina dSph galaxy from the analysis of individual CCD images obtained for a deep photometric study of the system. | | | The ratio of dwarf Cepheids to RR Lyr stars in Carina is 0.13 +/- 0.10, though this result is highly sensitive to the star-formation history of Carina and the evolution of the Horizontal Branch. |
|
http://citebase.eprints.org/cgi-bin/citations?id=oai%3AarXiv%2Eorg%3Aastro%2Dph%2F9807233
(925 words)
|
|
| |
| | Chandra :: Educational Materials :: Stellar Evolution :: Stellar Cycles Post Assessment Activity |
| | Dana Berry illustration of a red giant and white dwarf in a binary system. | | | Sirius B (dim object in the background) is a white dwarf in a binary system with Sirius A (bright object in the foreground) - a 2 solar mass main sequence star. | | | A Cepheid variable star light curve which is a stage that many lower high mass stars evolve through (Cepheid instability strip on the H-R diagram) on their way to the red supergiant branch of the H-R diagram. |
|
http://chandra.harvard.edu/edu/formal/stellar_cycle/image_desc.html
(508 words)
|
|
| |
| | Catalogue: J/AJ/110/2166 |
| | We have identified 44 variables: 36 RR Lyr star, 6 anomalous Cepheids, one long-period red variable, all probable members of Sextans, and one foreground contact binary. | | | We have used the pulsating stars to derive a true distance modulus of 19.67±0.15 for Sextans (or D=86±6kpc), where the error is primarily due to uncertainties in the luminosity-metallicity relation for RR Lyr stars. | | | This file × table2 65 161 Log of Sextans observations × table8 38 1038 B-band photometry of the Sextans variables × table9 38 560 V-band photometry of the Sextans variables × table10 72 2852 Photometry of non-variable stars in the deep Sextans images |
|
http://cdsweb.u-strasbg.fr/cgi-bin/Cat?J/AJ/110/2166
(508 words)
|
|
| |
| | Citebase - Dwarf Cepheids in the Carina Dwarf Spheroidal Galaxy |
| | The thin red giant branch (RGB) of the Carina dwarf spheroidal galaxy appears at first sight quite puzzling and seemingly in contrast with the presence of several distinct bursts of star formation. | | | We have discovered 20 dwarf Cepheids (DC) in the Carina dSph galaxy from the analysis of individual CCD images obtained for a deep photometric study of the system. | | | The ratio of dwarf Cepheids to RR Lyr stars in Carina is 0.13 +/- 0.10, though this result is highly sensitive to the star-formation history of Carina and the evolution of the Horizontal Branch. |
|
http://citebase.eprints.org/cgi-bin/citations?id=oai%3AarXiv%2Eorg%3Aastro%2Dph%2F9807233
(508 words)
|
|
| |
| | Gliese 876 / Ross 780 |
| | Since this red dwarf star is so cool and dim, its habitable zone may be located at around one to two tenths -- 0.112 to 0.221 AU -- of the Earth-Sun distance (Jones and Sleep, 2003), given a bolometric luminosity around 0.124. | | | Furthermore, past analyses with infrared speckle interferometry indicated that the star does not have large companions between one and 10 AU of the star (Henry and McCarthy, 1990; and Leinert et al, 1997). | | | For more information about stars including spectral and luminosity class codes, go to ChView's webpage on The Stars of the Milky Way. |
|
http://www.solstation.com/stars/gl876.htm
(508 words)
|
|
| |
| | Remote Sensing Tutorial Page Section20-2a |
| | Other opinions favor elliptical galaxies (with their pre-eminent old stars) were the primordial type, at least those which may constitute AGN's in spirals, but most of these subsequently captured gases that organized in the stars occupying the arms that characterize Spiral Galaxies. | | | These are created intermittently over short periods of time (for most of their history, dwarf galaxies tend to be quiescent in terms of new star production) at rates up to 100 times greater than spiral galaxies (in the latter, a new star is generated on average once a year over the entire system). | | | One way to illustrate this is shown in this Hubble Deep Field image, in which the numbers shown next to galactic bodies are their computed red shifts (see page 20-9 for a review of this topic). |
|
http://rst.gsfc.nasa.gov/sect20/A2a.html
(508 words)
|
|
| |
| | WFPC2 |
| | Much as a butterfly emerges when its chrysalis is ejected, planetary nebulae are formed when a red giant star ejectes its outer layers as clouds of luminescent gas, revealing the dense, hot, and tiny white dwarf star at its core. | | | The set of images below are of three nebulae known as "butterfly", "bow-tie", or bipolar nebulae. | | | A far better name for these objects would be "ejection nebulae". |
|
http://www.astro.washington.edu/balick/WFPC2
(508 words)
|
|
| |
| | AllRefer.com - spectral class (Astronomy, General) - Encyclopedia |
| | A bright supergiant is Ia, a faint supergiant is Ib, a bright giant is II, a normal giant is III, a subgiant is IV, and a normal dwarf or main-sequence star is V. For example, Sirius is classed as A1 V, a main-sequence white star. | | | According to a system introduced by W. Morgan and others, a Roman numeral is added to the spectral class to specify the luminosity, or intrinsic intensity, of a star. | | | This work culminated in the publication of the Henry Draper Catalogue (1924), which lists the spectral classes of 255,000 stars. |
|
http://reference.allrefer.com/encyclopedia/S/spectral.html
(394 words)
|
|
| |
| | R Aquarii |
| | At the centre of the nebula is a symbiotic star, an interacting pair consisting of a red giant and white dwarf. | | | The white dwarf itself is invisible and the light from the red dwarf is truly red, perhaps because the whole system is embedded in very dusty nebula which absorbs what blue light there is. | | | The dwarf draws in material from the giant, occasionally ejecting the surplus as the strange loops seen in the colour picture. |
|
http://www.aao.gov.au/images/captions/aat087.html
(145 words)
|
|
| |
| | Zoom Astronomy Glossary: R |
| | A red dwarf is a small, cool, very faint, main sequence star whose surface temperature is under about 4,000 K. Red dwarfs are the most common type of star. | | | This increase in wavelength makes the object appear to be redder than it actually is. For example, when a star is travelling away from Earth, its light appears redder (the light waves are elongated, lengthening the wavelength). | | | A red supergiant is a relatively old star whose diameter is about 100 times bigger than it was originally, and had become cooler (the surface temperature is under 6,500 K). |
|
http://www.enchantedlearning.com/subjects/astronomy/glossary/indexr.shtml
(2336 words)
|
|
| |
| | Red Dwarf References List |
| | The captain of the Red Dwarf was saddled with this name, made famous by Canadian-born American actor William Shatner (1931-) in the "Star Trek" series and movies via his portrayal of Captain James Tiberius Kirk. | | | The RED DWARF's shuttle crafts' names (excepting Starbug) are also types of stars. | | | A Who's Who, Where's Where, When was When and What's from What of RED DWARF. |
|
http://www.fortunecity.com/underworld/f22/161/rdrl.html
(2336 words)
|
|
| |
| | Lecture Notes |
| | Red dwarf stars are dim and have a low temperature. | | | A main sequence star may become a red giant or a supergiant. | | | A red giant is a star that expands and cools once it uses all of its hydrogen. |
|
http://www.usd.edu/~skfannin/lectureast7.htm
(1793 words)
|
|
| |
| | Aldebaran / Alpha Tauri 2 |
| | Star "B" is a red red sequence dwarf star of spectral and luminosity type M2 V. It may have 15 percent of Sol's mass, 36 percent of its diameter, and 14/10,000th of its luminosity. | | | According to the Yale Bright Star Catalogue, 1991 5th Revised Edition notes entry for HR 1457, two determinations of diameter were estimated (0.022" and 0.0237"), and Magnesium-II emissions indicate a cooler shell of gas and dust surrounding Star A (with an infrared emission determination of the envelope diameter to be 10"). | | | Aldebaran, or Alpha Tauri, is a binary star system located around 65.1 light-years (ly) from Sol. |
|
http://www.solstation.com/stars2/aldebaran.htm
(1793 words)
|
|
| |
| | 40 |
| | We derive the V luminosity profile, the surface density profile of resolved stars, and the structural parameters of Tucana, from which we confirm that Tucana participates to the general metallicity-surface brightness-absolute magnitude relations defined by the Galaxy and M31 dwarf spheroidal and dwarf elliptical companions. | | | From the I magnitude of the tip of the red giant branch we estimate a distance modulus (m-M)_0_=24.69+/-0.16, corresponding to 870+/-60Kpc, confirming that Tucana is an isolated dwarf spheroidal located almost at the border of the Local Group. | | | The color-magnitude diagram indicates that Tucana has had a single star formation burst at the epoch of the Galactic globular cluster star formation. |
|
http://xml.gsfc.nasa.gov/archive/journals/A+A/315/40
(1793 words)
|
|
| |
| | Zoom Astronomy Glossary: B |
| | This dark star is what remains after a red giant star loses its outer layers, forming a planetary nebula and then a white dwarf. | | | A brown dwarf is a "star" whose mass is too small to have nuclear fusion occur at its core (the temperature and pressure at its core are insufficient for fusion) - a failed star. | | | For another example, if two objects have magnitudes of 2 and 7 (a difference of 5), their brightness ratio is 2.512 raised to the 5th power, which is about 100. |
|
http://www.enchantedlearning.com/subjects/astronomy/glossary/indexb.shtml
(1793 words)
|
|
| |
| | Twenty-Four Young Earth Arguments Refuted |
| | Indeed, there are stars of all sizes, from miniscule red dwarf stars, through to immense supergiant stars, with our sun somewhere on between. | | | There are no binary stars in which the two are classified as being of different ages. | | | The Formation of Common Envelope, Pre Main Sequence Binary Stars |
|
http://www.tim-thompson.com/young-earth2.html
(1793 words)
|
|
|
