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Delta Cancri
Delta Cancri (δ Cancri, abbreviated Delta Cnc, δ Cnc) is a double star about 180 light-years from the Sun in the constellation of Cancer. Its two main constituents are designated Delta Cancri A and B. A is itself a binary star whose components are Delta Cancri Aa (formally named Asellus Australis , the traditional name of the entire system) and Ab. The star system is 0.08 degree north of the ecliptic, so it can be occulted by the Moon and more rarely by planets; it is occulted (eclipsed) by the sun from about 31 July to 2 August. Thus the star can be viewed the whole night, crossing the sky at the start of February. Nomenclature ''δ Cancri'' ( Latinised to ''Delta Cancri'') is the system's Bayer designation. The designations of the two constituents ''Delta Cancri A'' and ''B'', and those of ''A's'' components - ''Delta Cancri Aa'' and ''Ab'' - derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiple Star
A star system or stellar system is a small number of stars that orbit each other, bound by gravitational attraction. A large group of stars bound by gravitation is generally called a ''star cluster'' or ''galaxy'', although, broadly speaking, they are also star systems. Star systems are not to be confused with planetary systems, which include planets and similar bodies (such as comets). A star system of two stars is known as a ''binary star'', ''binary star system'' or ''physical double star''. If there are no tidal effects, no perturbation from other forces, and no transfer of mass from one star to the other, such a system is stable, and both stars will trace out an elliptical orbit around the barycenter of the system indefinitely. ''(See Two-body problem)''. Examples of binary systems are Sirius, Procyon and Cygnus X-1, the last of which probably consists of a star and a black hole. Multiple star systems A multiple star system consists of three or more stars that appear f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayer Objects
Bayer AG (, commonly pronounced ; ) is a German multinational pharmaceutical and biotechnology company and one of the largest pharmaceutical companies in the world. Headquartered in Leverkusen, Bayer's areas of business include pharmaceuticals; consumer healthcare products, agricultural chemicals, seeds and biotechnology products. The company is a component of the Euro Stoxx 50 stock market index. Bayer was founded in 1863 in Barmen as a partnership between dye salesman Friedrich Bayer and dyer Friedrich Weskott. As was common in this era, the company was established as a dyestuffs producer. The versatility of aniline chemistry led Bayer to expand their business into other areas, and in 1899 Bayer launched the compound acetylsalicylic acid under the trademarked name Aspirin. In 1904 Bayer received a trademark for the "Bayer Cross" logo, which was subsequently stamped onto each aspirin tablet, creating an iconic product that is still sold by Bayer. Other commonly known produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta Cancrids
The Delta Cancrids is a medium strength meteor shower lasting from December 14 to February 14, the main shower from January 1 to January 24. The radiant is located in the constellation of Cancer, near Delta Cancri Delta Cancri (δ Cancri, abbreviated Delta Cnc, δ Cnc) is a double star about 180 light-years from the Sun in the constellation of Cancer. Its two main constituents are designated Delta Cancri A and B. A is itself a binary star whose co .... It peaks on January 17 each year, with only four meteors per hour. It was first discovered in 1872, but the first solid evidence of this phenomenon came in 1971. The source of this meteor shower is unknown, it has been suggested that it is similar to the orbit of asteroid 2001 YB5. References Meteor showers December events January events February events {{meteoroid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beehive Cluster
The Beehive Cluster (also known as Praesepe (Latin for "manger" or "crib"), M44, NGC 2632, or Cr 189), is an open cluster in the constellation Cancer. One of the nearest open clusters to Earth, it contains a larger population of stars than other nearby bright open clusters holding around 1,000 stars. Under dark skies, the Beehive Cluster looks like a small nebulous object to the naked eye, and has been known since ancient times. Classical astronomer Ptolemy described it as a "nebulous mass in the breast of Cancer". It was among the first objects that Galileo studied with his telescope. Age and proper motion coincide with those of the Hyades, suggesting they may share similar origins. Both clusters also contain red giants and white dwarfs, which represent later stages of stellar evolution, along with many main sequence stars. Distance to M44 is often cited to be between 160 and 187 parsecs (520–610 light years), but the revised Hipparcos parallaxes (2009) for Praesepe membe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hong Kong Space Museum
The Hong Kong Space Museum is an astronomy and space science museum located in Tsim Sha Tsui, Hong Kong. Opened on 8 October 1980, it is managed by the Leisure and Cultural Services Department of the Hong Kong Government. The building is notable for its hemispherical shape, which contains a planetarium, the only one in Hong Kong. The main facilities of the museum are located in a building next to the planetarium, showcasing information about the Solar System, cosmology, and spaceflight. Accessible from Salisbury Road, it is adjacent to the Hong Kong Cultural Centre, the Hong Kong Museum of Art, and the Tsim Sha Tsui Clock Tower. The Hong Kong Science Museum and the Hong Kong Museum of History are also located in Tsim Sha Tsui. History The idea of a planetarium was originally proposed in 1961 by the Urban Council. Ten years later, the Urban Services Department (USD) set up a working group to study overseas experience in establishing planetariums. The study was aimed at layi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eta Cancri
Eta Cancri, Latinized from η Cancri, is a single, orange-hued star in the zodiac constellation of Cancer. It is a faint star but visible to the naked eye with an apparent visual magnitude of 5.34. The annual parallax shift of 10.93 mas as seen from Earth yields a distance estimate of 155 light years from the Sun. It is moving further away with a radial velocity of +22 km/s. A stellar classification of K3 III for Eta Cancri indicates that, at the estimated age of 3.9 billion years old, it has left the main sequence and become an evolved giant star. The spectrum shows unusually strong absorption lines of cyanogen. It has 1.5 times the mass of the Sun and has expanded to 17 times the Sun's radius. The star is radiating 87 times the Sun's luminosity from its photosphere at an effective temperature of around 4,415 K. In Chinese astronomy, ''Ghost'' () refers to an asterism consisting of Theta Cancri, Eta Cancri, Gamma Cancri and Delta Cancri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theta Cancri
Theta Cancri, Latinised from θ Cancri, is a multiple star system in the zodiac constellation of Cancer. It is visible to the naked eye as a dim point of light with an apparent visual magnitude of +5.32. The system is located at a distance of approximately 450 light-years away from the Sun, based on parallax, and is drifting further away with a radial velocity of +44 km/s. Since it is near the ecliptic, it can be occulted by the Moon and, very rarely, by planets. The primary, designated component A, is K-type giant star with a stellar classification of K5 III, having exhausted the supply of hydrogen at its core, then cooled and expanded. At present it has 40 times the girth of the Sun. It is radiating 353 times the luminosity of the Sun at an effective temperature of . In Chinese astronomy, ''Ghost'' () refers to an asterism consisting of Theta Cancri, Eta Cancri, Gamma Cancri and Delta Cancri Delta Cancri (δ Cancri, abbreviated Delta Cnc, δ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asterism (astronomy)
An asterism is an observed pattern or group of stars in the sky. Asterisms can be any identified pattern or group of stars, and therefore are a more general concept than the formally defined 88 constellations. Constellations are based on asterisms, but unlike asterisms, constellations outline and today completely divide the sky and all its celestial objects into regions around their central asterisms. For example, the asterism known as the Big Dipper comprises the seven brightest stars in the constellation Ursa Major. Another is the asterism of the Southern Cross, within the constellation of Crux. Asterisms range from simple shapes of just a few stars to more complex collections of many stars covering large portions of the sky. The stars themselves may be bright naked-eye objects or fainter, even telescopic, but they are generally all of a similar brightness to each other. The larger brighter asterisms are useful for people who are familiarizing themselves with the night sky. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ghost (Chinese Constellation)
The Ghost mansion () is one of the Twenty-eight mansions of the Chinese constellations. It is one of the southern mansions of the Vermilion Bird The Vermilion Bird ( zh, c=朱雀, p=Zhūquè) is one of the Four Symbols of the Chinese constellations. According to Wu Xing, the Taoist five elemental system, it represents the Fire element, the direction south, and the season summer correspo .... Asterisms {{DEFAULTSORT:Ghost (Chinese Constellation) Chinese constellations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinese Astronomy
Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categorized in the twenty-eight mansions have been found on oracle bones unearthed at Anyang, dating back to the mid-Shang dynasty. The core of the "mansion" (宿 ''xiù'') system also took shape around this period, by the time of King Wu Ding (1250–1192 BCE). Detailed records of astronomical observations began during the Warring States period (fourth century BCE) and flourished from the Han period onward. Chinese astronomy was equatorial, centered on close observation of circumpolar stars, and was based on different principles from those in traditional Western astronomy, where heliacal risings and settings of zodiac constellations formed the basic ecliptic framework. Joseph Needham has described the ancient Chinese as the most persistent and accurate obser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Their Lore And Meaning
In Modern English, ''they'' is a third-person pronoun relating to a grammatical subject. Morphology In Standard Modern English, ''they'' has five distinct word forms: * ''they'': the nominative (subjective) form * ''them'': the accusative (objective, called the ' oblique'.) and a non-standard determinative form. * ''their:'' the dependent genitive (possessive) form * ''theirs'': independent genitive form * ''themselves'': prototypical reflexive form *''themself'': derivative reflexive form (nonstandard; now chiefly used instead of "himself or herself" as a reflexive epicenity for ''they'' in pronominal reference to a singular referent) History Old English had a single third-person pronoun '' hē'', which had both singular and plural forms, and ''they'' wasn't among them. In or about the start of the 13th century, ''they'' was imported from a Scandinavian source (Old Norse ''þeir'', Old Danish, Old Swedish ''þer'', ''þair''), where it was a masculine plural demo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
