"and . Polaris B can be seen even with a modest telescope. William Herschel discovered the star in August 1779 using a reflecting telescope of his own, one of the best telescopes of the time. By examining the spectrum of Polaris A, it was also discovered in 1929 that it was a very close binary, with the secondary being a dwarf (variously UMi P, UMi an or UMi Ab), which had been theorized in earlier observations (Moore, J. H. and Kholodovsky, E. A.). In January 2006, NASA released images, from the Hubble telescope, that showed the three members of the"
"the North Star. Polaris, the brightest star in the constellation, is a yellow-white supergiant and the brightest Cepheid variable star in the night sky, ranging from an apparent magnitude of 1.97 to 2.00. Beta Ursae Minoris, also known as Kochab, is an aging star that has swollen and cooled to become an orange giant with an apparent magnitude of 2.08, only slightly fainter than Polaris. Kochab and magnitude 3 Gamma Ursae Minoris have been called the ""guardians of the pole star"". Planets have been detected orbiting four of the stars, including Kochab. The constellation also contains an isolated neutron star—Calvera—and"
"Polaris is also known as the North Star, and is generically called a pole star or lodestar. Polaris is only visible during fair weather at night to inhabitants of the Northern Hemisphere. The asterism ""Big Dipper"" may be used to find Polaris. The 2 corner stars of the ""pan"" (those opposite from the handle) point above the top of the ""pan"" to Polaris. While observers in the Northern hemisphere can use the star Polaris to determine the Northern celestial pole, the Octans constellation's South Star is hardly visible enough to use for navigation. For this reason, the preferred alternative is"
"variable star. It is a spectroscopic binary, with a companion 0.36 AU distant, and a third star—an orange main-sequence star of spectral type K0—8100 AU distant. Located close to Polaris is Lambda Ursae Minoris, a red giant of spectral type M1III. It is a semiregular variable varying from magnitudes 6.35 to 6.45. The northerly nature of the constellation means that the variable stars can be observed all year: the red giant R Ursae Minoris is a semiregular variable varying from magnitude 8.5 to 11.5 over 328 days, while S Ursae Minoris is a long period variable that ranges between magnitudes"
"Polar (star) A Polar is a highly magnetic type of cataclysmic variable binary star system, originally known as an AM Herculis star after the prototype member AM Herculis. Like other cataclysmic variables (CVs), polars contain two stars: an accreting white dwarf (WD), and a low-mass donor star (usually a red dwarf) which is transferring mass to the WD as a result of the WD's gravitational pull, overflowing its Roche lobe. Polars are distinguished from other CVs by the presence of a very strong magnetic field in the WD. Typical magnetic field strengths of polar systems are 10 million to 80"
"remain in use, likely because of their proximity to the north celestial pole. Within the constellation's borders, there are 39 stars brighter than or equal to apparent magnitude 6.5. Marking the Little Bear's tail, Polaris, or Alpha Ursae Minoris, is the brightest star in the constellation, varying between apparent magnitude 1.97 and 2.00 over a period of 3.97 days. Located around 432 light-years away from Earth, it is a yellow-white supergiant that varies between spectral types F7Ib and F8Ib, and has around 6 times the Sun's mass, 2,500 times its luminosity and 45 times its radius. Polaris is the brightest"
"which time the pole of the Earth's rotation follows a circular path across the celestial sphere that passes near several prominent stars. At present the pole star is Polaris, but around 12,000 BC the pole was pointed only five degrees away from Vega. Through precession, the pole will again pass near Vega around AD 14,000. Vega is the brightest of the successive northern pole stars. This star lies at a vertex of a widely spaced asterism called the Summer Triangle, which consists of Vega plus the two first-magnitude stars Altair, in Aquila, and Deneb in Cygnus. This formation is the"
"Pole star A pole star or polar star is a star, preferably bright, closely aligned to the axis of rotation of an astronomical object. With regard to planet Earth, the pole star refers to Polaris (Alpha Ursae Minoris), a magnitude 2 star aligned approximately with its northern axis, and a pre-eminent star in celestial navigation. In classical antiquity, Beta Ursae Minoris (Kochab) was closer to the celestial north pole than Alpha Ursae Minoris. While there was no naked-eye star close to the pole, the midpoint between Alpha and Beta Ursae Minoris was reasonably close to the pole, and it appears"
"a subsequent immortal existence in the realm of the stars). A consequence of the precession is a changing pole star. Currently Polaris is extremely well suited to mark the position of the north celestial pole, as Polaris is a moderately bright star with a visual magnitude of 2.1 (variable), and it is located about one degree from the pole, with no stars of similar brightness too close. The previous pole star was Kochab (Beta Ursae Minoris, β UMi, β Ursae Minoris), the brightest star in the bowl of the ""Little Dipper"", located 16 degrees from Polaris. It held that role"
"southern hemisphere's pole star it bore the name ""Polaris Australis"", first applied in the 1700s. In 2016, the IAU organized a Working Group on Star Names (WGSN) to catalog and standardize proper names for stars. The WGSN approved the name ""Polaris Australis"" for this star on 5 September 2017 and it is now so included in the List of IAU-approved Star Names. It is the southernmost named star. Sigma Octantis is the southern pole star, whose counterpart is Polaris, the current North Star. To an observer in the southern hemisphere, Sigma Octantis appears almost motionless and all the other stars"
"system, even if it exists, may not be suited for life, because it is a super giant type F7Ib star in a triple star system [with nearby companions] which should (to present knowledge) possess very powerful stellar winds around its vicinity. In addition to this, the age of Polaris has been calculated to be approximately 70 million years and thus this star may be too young to support the development of life. Another IRM entitled Across the Universe was previously sent towards this stellar location by NASA's nearby MDSCC facility in 2008. This transmission consisted of four components in the"
"12,000 years, Vega (Alpha Lyrae) will become our north star, but it will be about six degrees from the true north celestial pole. To find Polaris, face north and locate the Big Dipper (Plough) and Little Dipper asterisms. Looking at the ""cup"" part of the Big Dipper, imagine that the two stars at the outside edge of the cup form a line pointing upward out of the cup. This line points directly at the star at the tip of the Little Dipper's handle. That star is Polaris, the North Star. The south celestial pole is visible only from the Southern"
"mansion (see : Chinese constellation). 31 Comae Berenices 31 Comae Berenices (31 Com) is a yellow giant star in the constellation Coma Berenices. Its apparent magnitude is 4.94. It is a rare FK Comae Berenices variable, a variable star that spins rapidly and has large starspots on its surface. 31 Com is the north galactic pole star, and occasionally goes by the informal name Polaris Galacticum Borealis, coined by Jim Kaler. In Chinese astronomy, 31 Comae Berenices is called 郎將, Pinyin: Lángjiāng, meaning ""Captain of the Bodyguards"", because this star is marking itself and stand alone in ""Captain of the"
"the binary. DP Leonis DP Leonis (abbreviated DP Leo) is an eclipsing binary system approximately 1304 light-years away from the Sun, probably a cataclysmic variable star of the ""AM Herculis""-type also known as ""polars"". The system comprises an eclipsing white dwarf and red dwarf in tight orbit (nearly 1.5 hours) and an extrasolar planet. In 2010, Qian ""et al."" announced the detection of a third body of planetary mass around the eclipsing binary system. The presence of a third body had already been suspected in 2002. The object is roughly 6 times more massive than Jupiter and is located 8.6"
"and together they are called the Ursa Major Moving Group. The stars Merak (β Ursae Majoris) and Dubhe (α Ursae Majoris) are known as the ""pointer stars"" because they are helpful for finding Polaris, also known as the North Star or Pole Star. By visually tracing a line from Merak through Dubhe (1 unit) and continuing for 5 units, one's eye will land on Polaris, accurately indicating true north. Another asterism known as the ""Three Leaps of the Gazelle"" is recognized in Arab culture, a series of three pairs of stars found along the southern border of the constellation; From"
"Monoceros Monoceros (Greek: Μονόκερως) is a faint constellation on the celestial equator. Its name is Greek for unicorn. Its definition is attributed to the 17th-century Dutch cartographer Petrus Plancius. It is bordered by Orion to the west, Gemini to the north, Canis Major to the south and Hydra to the east. Other bordering constellations include Canis Minor, Lepus and Puppis. Monoceros is not easily seen with the naked eye, containing only a few fourth magnitude stars. Alpha Monocerotis has a visual magnitude of 3.93, slightly brighter than Gamma Monocerotis at 3.98. Beta Monocerotis is a triple star system, the three"
"by the appearance and eclipse of the accreting regions during rotation of the white dwarf. AM Herculis AM Herculis is a binary variable star located in the constellation Hercules. This star, along with the star ""AN Ursae Majoris"", is the prototype for a category of cataclysmic variable stars called ""polars"", or ""AM Her"" type stars. AM Herculis and was first cataloged in 1923 by Max Wolf and was listed at the time as ""Veränderlicher 28.1923"", which is now ""AN 28.1923"" in the ""General Catalogue of Variable Stars"". It was observed to be an irregular variable star ranging from 12 to"
"Polaris, which is slightly brighter and will have a much closer alignment of less than 0.5° by 2100 AD. This change in the identity of the pole stars is a result of Earth's precessional motion. After 2000 BCE, Kochab and a new star, its neighbor Pherkad, were closer to the pole and together served as twin pole stars, circling the North Pole, from around 1700 BCE until just after 300 AD. Neither star was as proximitous to the celestial north pole as Polaris is now. Today, they are sometimes referred to as the ""Guardians of the Pole."" Estimated to be"
"(discovered in August 1779 by William Herschel). There were once thought to be two more distant components—Polaris C and Polaris D—but these have been shown not to be physically associated with the Polaris system. Polaris Aa is a 5.4 solar mass () F7 yellow supergiant of spectral type Ib. This is the first classical Cepheid to have a mass determined from its orbit. The two smaller companions are Polaris B, a F3 main-sequence star orbiting at a distance of 2400 astronomical units (au), and Polaris Ab (or P), a very close F6 main-sequence star with an 18.8 au radius orbit"
"Musca Borealis Musca Borealis (Latin for ""northern fly"") was a constellation, now discarded, located between the constellations of Aries and Perseus. It was originally called Apes (plural of Apis, Latin for bee) by Petrus Plancius when he created it in 1612. It was made up of a small group of stars, now called 33 Arietis, 35 Arietis, 39 Arietis, and 41 Arietis, in the north of the constellation of Aries. The brightest star is now known as 41 Arietis. At magnitude 3.63, it is a blue-white main sequence star of spectral type B8V around 166 light-years distant. 39 Arietis is"
"Theta2 Orionis Theta Orionis (θ Ori) is a multiple star system in the constellation Orion. It is a few arc minutes from its more famous neighbour the Trapezium Cluster, also known as θ Orionis. θ Orionis consists of three stars in a line, each about an arc-minute from the next. In addition to the well-known three stars, the Washington Double Star Catalog confusingly lists a component D which is actually θ Orionis C. There is one other star brighter than 10th magnitude in the region. V1073 Orionis is a B9.5 Orion variable that forms an equilateral triangle with θ Ori"
"31 Comae Berenices 31 Comae Berenices (31 Com) is a yellow giant star in the constellation Coma Berenices. Its apparent magnitude is 4.94. It is a rare FK Comae Berenices variable, a variable star that spins rapidly and has large starspots on its surface. 31 Com is the north galactic pole star, and occasionally goes by the informal name Polaris Galacticum Borealis, coined by Jim Kaler. In Chinese astronomy, 31 Comae Berenices is called 郎將, Pinyin: Lángjiāng, meaning ""Captain of the Bodyguards"", because this star is marking itself and stand alone in ""Captain of the Bodyguards"" asterism, Supreme Palace enclosure"
"again around the year 14,000); however, it never comes closer than 5° to the pole. When Polaris becomes the north star again around 27,800, due to its proper motion it then will be farther away from the pole than it is now, while in 23,600 BC it came closer to the pole. It is more difficult to find the south celestial pole in the sky at this moment, as that area is a particularly bland portion of the sky, and the nominal south pole star is Sigma Octantis, which with magnitude 5.5 is barely visible to the naked eye even"
"DP Leonis DP Leonis (abbreviated DP Leo) is an eclipsing binary system approximately 1304 light-years away from the Sun, probably a cataclysmic variable star of the ""AM Herculis""-type also known as ""polars"". The system comprises an eclipsing white dwarf and red dwarf in tight orbit (nearly 1.5 hours) and an extrasolar planet. In 2010, Qian ""et al."" announced the detection of a third body of planetary mass around the eclipsing binary system. The presence of a third body had already been suspected in 2002. The object is roughly 6 times more massive than Jupiter and is located 8.6 AU from"
"Polaris ternary system. The nearest dwarf star is in an orbit of only 18.5 au (2.8 billion km) from Polaris A, about the distance between the Sun and Uranus), which explains why its light is swamped by its close and much brighter companion. Polaris A, the supergiant primary component, is a low-amplitude Population I classical Cepheid variable, although it was once thought to be a type II Cepheid due to its high galactic latitude. Cepheids constitute an important standard candle for determining distance, so Polaris, as the closest such star, is heavily studied. The variability of Polaris had been suspected"
"of one another by following various lines traced through various stars in Orion. The stars in the hexagon are parts of six constellations. Counter-clockwise around the hexagon, starting with Rigel, these are Orion, Taurus, Auriga, Gemini, Canis Minor, and Canis Major. Winter Hexagon The Winter Hexagon or Winter Circle/Oval is an asterism appearing to be in the form of a hexagon with vertices at Rigel, Aldebaran, Capella, Pollux, Procyon, and Sirius. It is mostly upon the Northern Hemisphere's celestial sphere. On most locations on Earth (except the South Island of New Zealand and the south of Chile and Argentina and"
"multiple pulsation frequencies. Epsilon Persei Epsilon Persei (ε Persei, ε Per) is a multiple star system in the northern constellation of Perseus. It has a combined apparent visual magnitude of +2.88, which is bright enough to be viewed with the naked eye. Based upon parallax measurements, this system is located at a distance of roughly 640 light-years (196 parsecs) from Earth. This is a spectroscopic binary system, which means that the presence of an orbiting companion has been revealed by radial velocity variations in the spectrum of the primary. The two components are orbiting each other with a period of"
"in 2012. There are two faint deep-sky objects within the constellation's borders. The 11 Canis-Minorids are a meteor shower that can be seen in early December. Though strongly associated with the Classical Greek uranographic tradition, Canis Minor originates from ancient Mesopotamia. Procyon and Gomeisa were called ""MASH.TAB.BA"" or ""twins"" in the ""Three Stars Each"" tablets, dating to around 1100 BC. In the later ""MUL.APIN"", this name was also applied to the pairs of Pi and Pi Orionis and Zeta and Xi Orionis. The meaning of ""MASH.TAB.BA"" evolved as well, becoming the twin deities Lulal and Latarak, who are on the"
"Mintaka Mintaka, also designated Delta Orionis (δ Orionis, abbreviated Delta Ori, δ Ori) and 34 Orionis (34 Ori) is a multiple star system some 1,200 light-years from the Sun in the constellation of Orion. Together with Alnitak (Zeta Orionis) and Alnilam (Epsilon Orionis), the three stars form Orion's Belt, known by many names among ancient cultures. When Orion is near the meridian, Mintaka is the right-most of the Belt's stars when viewed from the Northern Hemisphere facing south. ""Delta Orionis"" is the star's Bayer designation, ""34 Orionis"" its Flamsteed designation. The name ""Mintaka"" itself is derived from an Arabic term"
"Collinder 69 Collinder 69 (Lambda Orionis Association) is an open star cluster located north-west of the star Betelgeuse in the constellation of Orion. It is about five million years old and roughly away from the Sun. Included within the cluster is a double star named Meissa. With the rest of Orion, it is visible from the middle of August in the morning sky, to late April before Orion becomes too close to the Sun to be seen well. It can be seen from both the northern hemisphere and the southern hemisphere. The cluster is following an orbit through the Milky"
"the celestial sphere by the Earth's North pole. It was the northern pole star around the year 7400 BC, a phenomenon which is expected to reoccur in the year 18,400 due to precession. The current pole star is, of course, Polaris. Among the 14 stars that could be reasonably considered eventual northern pole stars, Tau Herculis is the dimmest, but only Polaris itself and Thuban are closer to the precessional path. Its traditional name, ""Rukbalgethi Shemali"", is of Arabic origin and shares certain etymological characteristics with the stars Ruchbah and Zubeneschamali, signifying Hercules' ""northern knee"". In Chinese, (), meaning ""Seven"
"A–B pair may be partially obscured due to dust in the disk as the pair approaches apoastron in the hierarchical orbit. GW Orionis GW Orionis is a T Tauri type pre-main sequence hierarchical triple star system. It is associated with the Lambda Orionis star-forming region and has an extended circumtrinary protoplanetary disk. GW Orionis first came to the attention of astronomers when it was published, as MHA 265-2, in a list of stars whose spectra have bright H and K lines of calcium. The multiple nature of GW Orionis was first discovered by Robert D. Mathieu, Fred Adams and David"
"either B and Ac, possibly due to an unseen companion or rotational modulation. The actual period is 0.432 days and the 0.3-day period was an alias. Eta Orionis Eta Orionis (η Orionis) is a multiple star in the constellation Orion. It lies a little to the west of Orion's belt between Delta Orionis and Rigel, being closer to Delta Orionis than to Rigel. It lies at a distance of around 1,000 light years from Earth and is part of the Orion OB1 association. The proper name Saiph is Arabic for ""sword"", and Algjebbah Arabic for ""scutum"". Eta Orionis is listed"