Polaris: The North Star – Alpha Ursae Minoris | Constellation Guide by admin Polaris, also known as the North Star, Alpha Ursae Minoris or Star of Arcady, is the brightest star in Ursa Minor constellation. Polaris is notable for currently being the closest bright star to the North Celestial Pole. The pole marks true north, which makes the North Star important in navigation, as the star’s elevation above the horizon closely matches the observer’s latitude. The North Star has a reputation for being bright, but it is not among the top 10 or even the top 40 brightest stars in the night sky. It is only the 48th brightest star, and owes its reputation to the fact that it is the nearest relatively bright (second magnitude) star to the North Celestial Pole. Polaris is also the star that marks the end of the Little Dipper ‘s handle. It is approximately 434 light years or 133 parsecs distant from Earth.

Polaris goes by many different names, including the Northern Star, Pole Star, Lodestar, Guiding Star, and Cynosūra, derived from the Greek κυνόσουρα for “the dog’s tail.” In ancient Greek times, Ursa Minor was taken to represent a dog, not a bear. The close view to the Polaris trinary star system. Credit: NASA, ESA, N. Evans (Harvard-Smithsonian CfA), and H. Bond (STScI) Most of the names used for Alpha Ursae Minoris (Alpha UMi) reflect the star’s role as the pole star. The name Polaris itself is an ellipsis for Stella Polaris, the Latin for “pole star.” In Latin, the star is also known as Stella Maris, or “the sea star.“ In medieval Islamic astronomy, Polaris was known as Mismar, meaning “needle” or “nail,” al-kaukab al-shamaliyy or “the north star,” and al-kutb al-shamaliyy or “the northern axle (or spindle).” Alpha Ursae Minoris is slightly off the pole, making a circle around it roughly 1.5 degrees across.

As a result of the 26,000 year precession of the Earth’s axis, the celestial pole is currently moving closer to Polaris. Once it reaches the separation of 14 arc minutes around the year 2105, the pole will start to move away from the star again. Eventually, another star will take over as the navigational benchmark for true north. LOCATION How to find the North Star Because the Little Dipper is not bright enough to be seen from areas where there is too much light pollution, the easiest way to locate the North Star is by using the stars of the bigger and brighter Big Dipper in the nearby Ursa Major constellation . Polaris, the North Star, is found by imagining a line from Merak (β) to Dubhe (α) and then extending it for five times the distance after Dubhe (α).

Legend: α UMa (Dubhe), β UMa (Merak), γ UMa (Phecda), δ UMa (Megrez), ε UMa (Alioth), ζ UMa (Mizar), η UMa (Alkaid) and α Ursae Minoris (Polaris), image: Alex Zelenko The stars Dubhe and Merak in Ursa Major , also known as the Pointers, are the easiest way to find Polaris. These are the two bright stars that outline the outer part of the bowl of the Big Dipper . An imaginary line through these stars leads directly to the North Star. Polaris is located at about five times the distance between the Pointer stars. It is the first bright star in that direction. The Big Dipper completes a circle around Polaris every 23 hours and 56 minutes, with the Pointer stars always pointing toward the North Star. The only nearby bright stars that are readily seen are Kochab and Pherkad, which are also part of the Little Dipper . The two stars are known as the “Guardians of the Pole” because they appear to march around the North Star like sentries.

Polaris marks the end of the handle of the Little Dipper , or the tip of the tail of the Smaller Bear . The stars of the Little Dipper are relatively faint and can only be seen without binoculars in good conditions, with clear skies, no light pollution, and little or no moonlight. Pole Star Polaris lies almost in a direct line with the Earth’s rotation axis, which is to say almost exactly “above” the North Pole. The star is almost motionless, with all the other stars in the northern sky seemingly rotating around it. The North Star never rises or sets at night, but stays in almost the same position above the northern horizon throughout the year, while other stars appear to circle around it. For observers at the North Pole, the star lies directly overhead. For observers in New York, it stands 41 degrees above the northern horizon, which corresponds to the latitude of the city. For observers at the equator, Polaris sits right on the horizon. The star clmbs higher in the sky the farther north you go and drops below the horizon for observers in the southern hemisphere.

Polaris star sytem, image: NASA Polaris was used as the pole star by navigators at least from Late Antiquity. It is currently 0.7° away from the pole and revolves around it in a small circle about one and a half degrees in diameter. Polaris wasn’t always the North Star. Around the year 2500 BC, the celestial pole was near Thuban, located in the constellation Draco . Around the year 400 BC, the pole was closer to Kochab, Beta Ursae Minoris, than it was to Alpha UMi. Around the year 14,000, the much brighter Vega in Lyra constellation will be the nearest star to the pole. Polaris will make its closest approach to the pole on March 24, 2100, when it will come within only 27.15 arc minutes of it. After the 21st century, the celestial pole will move away from Polaris and, by the 41st century, it will come near Gamma Cephei in Cepheus constellation .

Unlike the North Celestial Pole, the pole in the southern hemisphere doesn’t have a bright star close enough to be called the pole star, nor will it have one for the next 2,000 years. The nearest star to the south pole is Sigma Octantis, located in Octans constellation . With a visual magnitude of 5.45, it can barely be seen without binoculars, which doesn’t make it very useful in navigation. STAR SYSTEM Polaris is not a single star, but a multiple star system. The main component, Alpha Ursae Minoris Aa, is an evolved yellow supergiant star belonging to the spectral class F7. It is 2,500 times more luminous than the Sun, 4.5 times more massive, and has a radius 46 times that of the Sun. The star is classified as a Cepheid variable, showing pulsations over a period of about four days. Polaris A, image: NASA Polaris A is a classic Population I Cepheid variable. It is the brightest Cepheid variable in the sky. Cepheid variables are stars that astronomers use to measure distances to galaxies and clusters.

The North Star’s brightness varies by 0.03 magnitudes over a period of 3.97 days. Its variability had been theorized since 1852, but was not confirmed until 1911, when the Danish astronomer Ejnar Hertzsprung confirmed the variation. Polaris A’s amplitude and period of the variations have not remained the same since discovery. Before 1963, the amplitude was more than 0.1 magnitude and slowly decreasing. It decreased quite rapidly after 1966 until it reached 0.05 magnitude, and has been erratic but stayed neared that range since. The period of the variations increased more or less steadily until 1963, when it remained constant from 3 years, and then started increasing again. Currently, the measurements show a steady increase of 3.2 seconds per year. Diagram showing how to find the star Polaris by following the pointer stars in the Big Dipper. Alpha Ursae Minoris Aa has two companions. The one closer to the supergiant, designated Alpha Ursae Minoris Ab, is a dwarf belonging to the spectral class F7.

It lies at an average distance of 17 astronomical units and has an orbital period of about 29.6 years. The star has a highly eccentric orbit that takes it between 27 and 6.7 astronomical units from the primary component. The star further away from the supergiant, designated Alpha Ursae Minoris B, lies 18 arc seconds away. It is a dwarf star with the stellar classification F3 1.4. It is at least 2,400 astronomical units away from Polaris A and has an orbital period of at least 42,000 years. Polaris B was discovered by William Herschel in 1780. It can be seen in a modest telescope. Polaris also has two more distant companions, Alpha UMi C and Alpha UMi D. Polaris is the brightest in a small semicircle of stars known as the “Engagement Ring.” The stars lie within a field which is six degrees wide. The North Celestial Pole lies roughly halfway between Polaris and Lambda UMi. Polaris – Alpha Ursae Minoris. Image: NASA/ESA/HST, G.

Bacon (STScI) The binary nature of Polaris A was confirmed in 1929 after an examination of the star’s spectrum. All three components in the star system were revealed in Hubble images in January 2006. Polaris may be 2.5 times brighter today than when the Greek astronomer Ptolemy observed the star, according to a recent research led by Scott Engle of Villanova University in Pennsylvania. The research, based on historical records and presented in a poster session at the American Astronomical Society meeting in Washington, D.C., in January 2014, has revealed that the star has changed from third to second magnitude since Ptolemy’s times. Engle and his team used historic measurements of the star by Ptolemy in the year 137, the Persian astronomer Al Sufi in 964, the Danish astronomer Tycho Brahe in the 16th century, and others.

Polaris: Alpha Ursae Minoris Distance: 325 – 425 light years (99 – 129.5 parsecs) Coordinates: Alpha Ursae Minoris A – 02h 31m 49.09s (right ascension), +89°15’50.8” (declination) Alpha Ursae Minoris B – 02h 30m 41.63s (right ascension), +89°15’38.1” (declination) Apparent magnitude: 1.98v (Alpha Ursae Minoris Aa), 9.2 (Alpha Ursae Minoris Ab), 8.7 (Alpha Ursae Minoris B) Absolute magnitude: -3.6 (Alpha UMi Aa), 3.6 (Alpha UMi Ab), 3.1 (Alpha UMi B) Spectral class: F7Ib (Alpha UMi Aa), F6V (Alpha UMi Ab), F3V (Alpha UMi B) Variable type: Classical Cepheid (Alpha UMi Aa) Mass: 4.5 solar masses (

Alpha UMi Aa), 1.26 (Alpha UMi Ab), 1.39 (Alpha UMi B) Radius: 46±3 solar radii (Alpha UMi Aa), 1.04 (Alpha UMi Ab), 1.38 (Alpha UMi B) Luminosity: 2,500 solar luminosities (Alpha UMi Aa), 3 (Alpha UMi Ab), 3.9 (Alpha UMi B) Temperature: 6,015 K (Alpha Umi Aa), 6,900 (Alpha UMi B) Designations: Polaris, Alpha Ursae Minoris, North Star, 1 Ursae Minoris, Cynosura, Alruccabah, Star of Arcady.

Navigatoria, Yilduz, Mismar, HR 424, BD +88°8, HD 8890, SAO 308, FK5 907, GC 2243, ADS 1477, CCDM 02319+8915, HIP 11767 Polaris location. Image: Torsten Bronger Polaris is the North Star | Brightest Stars | EarthSky Polaris is the North Star By Bruce McClure in Brightest Stars | May 24, 2016 The entire northern sky wheels around Polaris. Some assume it’s the brightest star in the sky. In fact, Polaris ranks only 50th in brightness. Ken Christison captured these glorious star trails around Polaris, the North Star. See more photos from Ken Christison. The North Star or Pole Star – aka Polaris – is famous for holding nearly still in our sky while the entire northern sky moves around it. That’s because it’s located nearly at the north celestial pole, the point around which the entire northern sky turns. Polaris marks the way due north.

As you face Polaris and stretch your arms sideways, your right hand points due east, and your left hand points due west. About-face of Polaris steers you due south. Polaris is not the brightest star in the nighttime sky, as is commonly believed. It’s only about 50th brightest. But you can find it easily, and, once you do, you’ll see it shining in the northern sky every night, from N. Hemisphere locations. Follow the links below to learn more about Polaris. Polaris science Polaris on a stormy night. Spotting the North Star – and in that way knowing the direction north – has gladdened the heart of many a lost traveler. Photo by EarthSky Facebook friend Jv Noriega in the Philippines. If you can find the Big Dipper, you can find Polaris. The two outer stars in the bowl of the Dipper – Dubhe and Merak – always point to the North Star. Polaris marks the end of the Handle of the Little Dipper. Chart for early autumn evening Image via EarthSky Tonight How to see Polaris. This star is bright enough to spot even from some suburban skies.

In a dark country sky, even when the full moon obscures a good deal of the starry heavens, the North Star is relatively easy to see. That fact has made this star a boon to travelers throughout the Northern Hemisphere, both over land and sea. Finding Polaris means you know the direction north. Best of all, Polaris is readily found by using the prominent group of stars known as the Big Dipper , called the Plough in the UK, which may be the Northern Hemisphere’s most famous star pattern. To locate Polaris, all you have to do is to find the Big Dipper pointer stars Dubhe and Merak. These two stars outline the outer part of the Big Dipper’s bowl. Simply draw a line from Merak through Dubhe, and go about 5 times the Merak/Dubhe distance to Polaris. The Big Dipper, like a great big hour hand, goes full circle around Polaris in one day. More specifically, the Big Dipper circles Polaris in a counter-clockwise direction in 23 hours and 56 minutes.

Although the Big Dipper travels around Polaris all night long, the Big Dipper pointer stars always point to Polaris on any day of the year, and at any time of the night. Polaris marks the center of Nature’s grandest celestial clock! By the way, Polaris is famous for more reasons than one. It’s famous for hardly moving while the other stars wheel around it. And it’s famous for marking the end of the Little Dipper ‘s handle. The Little Dipper is tougher to spot in the night sky than the Big Dipper. But if you use the Big Dipper’s pointer stars to locate Polaris, you’ll be one step closer to seeing the Little Dipper. As you travel northward, Polaris climbs higher in the sky. If you go as far north as the North Pole, you’ll see Polaris directly overhead. As you travel south, Polaris drops closer to the northern horizon. If you get as far as the equator, Polaris sinks to the horizon. South of the equator, Polaris drops out of the sky. A planisphere is virtually indispensable for beginning stargazers. Order your EarthSky planisphere today.

When you take a time exposure photograph of the northern sky (or, in this case, the northeast), you see all the stars are moving around Polaris, which is on the left in this image. This image by Taro Yamamoto via an article on long exposure star trail photography. History of Polaris. Polaris hasn’t always been the North Star and won’t remain the North Star forever. For example, a famous star called Thuban, in the constellation Draco the Dragon, was the North Star when the Egyptians built the pyramids . But our present Polaris is a good North Star because it’s the sky’s 50th brightest star. So it’s noticeable in the sky. It served well as the North Star, for example, when the Europeans first sailed across the Atlantic over five centuries ago. And Polaris will continue its reign as the North Star for many centuries to come. It will align most closely with the north celestial pole – the point in the sky directly above Earth’s north rotational axis – on March 24, 2100.

The computational wizard Jean Meeus figures Polaris will be 27’09” (0.4525o) from the north celestial pole at that time (a little less than the angular diameter of the moon when at its farthest from Earth). Meanwhile, there is no visible star marking the celestial pole in the Southern Hemisphere. What’s more, the Southern Hemisphere won’t see a pole star appreciably close to the south celestial pole for another 2,000 years. At one time in human history, people literally depended on their lucky stars for their lives and livelihood. Luckily, they could trust the Big Dipper and the North Star to guide them. People could sail the seas and cross the trackless deserts without getting lost. When slavery existed in the United States, slaves counted on the Big Dipper (which they called the Drinking Gourd) to show them the North Star, lighting their way to the free states and Canada. While being honored as the North Star, Polaris enjoys the title of Lodestar and Cynosure as well. Does Mars have a North Star? An artist’s illustration of Polaris and its two known companion stars via the Hubble News Center. Polaris science.

The single point of light that we see as Polaris is actually a triple star system, or three stars orbiting a common center of mass. The primary star, Polaris A, is a supergiant with about six times the mass of our sun. A close companion, Polaris Ab, orbits 2 billion miles from Polaris. Much farther away, near the top of the illustration at right, is the third companion Polaris B. Polaris B is located approximately 240 billion miles from Polaris A. The two companion stars are the same temperature as Polaris A, but are dwarf stars. Astronomers estimate Polaris’ distance at 430 light-years . Considering the distance, Polaris must be a respectably luminous star. According to the star aficianado, Jim Kaler, Polaris is a yellow supergiant star shining with the luminosity of 2500 suns. Polaris is also the closest and brightest Cepheid variable star – a type of star that astronomers use to figure distances to star clusters and galaxies.

Polaris’ position is RA: 2h 31m 48.7s, dec: +89° 15′ 51″ The North Star: How to Find Polaris Start Over | More Quizzes Polaris Physical Facts Polaris is located at a distance of 434 light-years from Earth and has luminosity nearly 4,000 times that of our sun. Polaris shines at 2nd magnitude. On this astronomers’ scale, smaller numbers represent brighter objects, with the brightest stars and planets in the night sky at around magnitude zero or even negative magnitudes. The North Star it is a “pulsing” star, a Cepheid variable , which appears to vary in brightness ever so slightly – only one tenth of a magnitude – over a time frame of just under four days. If you have a small telescope and train it on Polaris, you just might notice a tiny companion star (called Polaris B) shining at 9th magnitude with a pale bluish tint. This companion was first sighted by Sir William Herschel in 1780 (just a year later, Herschel would discover the planet Uranus).

Astronomers believe that the two stars – A and B – are separated by about 2,400 astronomical units – one astronomical unit (a.u.) being the average distance of the sun to the Earth. The orbital period of the two stars may number in the many thousands of years. In 1929, by studying the spectrum of Polaris, a third companion star (Polaris C) was discovered. This one, a white dwarf, lies only 18.5 a.u. from Polaris A (about the same distance of the planet Uranus from our sun). Its extreme closeness to the far more brilliant Polaris A explains why it went unseen for so long. Using the North Star as a Guide Exactly where you see Polaris in your northern sky depends on your latitude. From New York it stands 41 degrees above the northern horizon, which also corresponds to the latitude of New York. Since 10 degrees is roughly equal to your clenched fist held at arm’s length, from New York Polaris would appear to stand about “four fists” above the northern horizon. At the North Pole, you would find it overhead. At the equator, Polaris would appear to sit right on the horizon.

So if you travel to the north, the North Star climbs progressively higher the farther north you go. When you head south, the star drops lower and ultimately disappears once you cross the equator and head into the Southern Hemisphere. And always keep this fact in mind: Polaris is more accurate than any compass. A compass is subject to periodic variations and can only show you the direction of the lines of the strongest magnetic force for a particular spot and for a particular time. But even Polaris isn’t positioned exactly due north. Only about 0.7 degree separates Polaris from the pivot point directly in the north – called the North Celestial Pole – around which the stars go daily. In case you’re wondering, 0.7 degree amounts to less than the apparent width of 1½ full moons. Guardians of the Pole Aside from the North Star the two stars at the front of the Little Dipper’s bowl are the only ones readily seen. These two are often referred to as the “Guardians of the Pole” because they appear to march around Polaris like sentries; the nearest conspicuously bright stars to the celestial pole except for Polaris itself.

Columbus mentioned these stars in the log of his famous journey across the ocean and many other navigators have found them useful in measuring the hour of the night and their place upon the sea by their position relative to Polaris. The brightest Guardian is Kochab, a second magnitude star with an orange hue. The other Guardian goes by an old Arabian name, Pherkad – the “Dim One of the Two Calves.” Pherkad is indeed dimmer than Kochab, shining at third magnitude. Not the only North Star There is a famous Shakespeare quote that has Julius Caesar stating, “I am constant as the northern star.” But in reality, Polaris is not really constant, at least over a time span measured over centuries, for it will not always be our North Star. Like a spinning top that wobbles due to a force called torque, our spinning earth is also subject to torque that is caused by the gravitational forces of the sun and moon. As a result the earth’s axis wobbles (called precession), and as a consequence describes a circle in the sky; the gradual change in the direction of the earth’s axis in space. So the north celestial pole shifts as the centuries go by.

Polaris is actually still drawing closer to the pole and on March 24, 2100, it will be as close to it as it ever will come, just 27.15 arc-minutes or slightly less than the Moon’s apparent diameter. Since it takes about 25,800-years for the Earth’s axis to complete a single wobble, different stars have become the North Star at different times. For example, the star Thuban in the constellation of Draco, the Dragon was the North Star around the year 2600 B.C., during the age of the Pyramid Builders of ancient Egypt. The brightest Guardian, Kochab, was the North Star at the time of Plato, around 400 BC. And around the year 14,000, earth’s axis will point reasonably close to the star Vega, one of the brightest stars in the sky; perhaps our future descendants will confer the title of North Star on it. Sources and More Reading: Polaris Magnitude: 2.1 The history of the star: Polaris Alpha (α) Ursa Minor , Polaris, is a star in the tip of the tail of the Little Bear.

Its name comes to us from Latin Stella Polaris, meaning "Pole Star". Polaris is our Pole star, situated at the north pole it never sets and as Wikipedia explains Polaris stands almost motionless on the sky, and all the stars of the Northern sky appear to rotate around it. Therefore, it makes an excellent fixed point from which to draw measurements for celestial navigation and for astrometry. Other stars along this circle were the pole star in the past and will be again in the future, including Thuban and Vega. Polaris has been close to the actual position of the north pole for over 1000 years. Polaris has long been an important star to sailors, caravans of old winding their way over the desert by night and others who navigated their way by the stars. Located almost directly overhead as seen from the North Pole, it is situated at the tip of the tail of the Little Bear, Ursa Minor and the brightest star of that constellation. Perhaps more than any star other than the Sun; Polaris has been regarded as the most important star in the heavens.

It has been known by many names in the past; "the Pathway" "the Pointer" - indicating the way; "Navel of the World", "Gate of Heaven", "Hub of the Cosmos", "the Highest Peak of the World Mountain", "Lodestar" "the Steering Star" "the Ship Star" and Stella Maris "Star of the Sea". Greek navigators of old called Polaris; Kynosoura, which means "the Dog's Tail". The name came into our English language as Cynosure, which means "an object that serves as a focal point of attention and admiration" or "Something that serves to guide". The proximity of the stars of the two bears ( Ursa Major and Ursa Minor ) to the North Celestial Pole gave the impression that they were wheeling around this point, pulling perhaps a plough behind them, tilling the heavenly fields and driven on by Bootes the Bear Driver who chases or herds the Bears around Polaris.

Another version of this story has it that the oxen were tied to the polar axis and were driven on by Bootes, assisted by his two dogs Canes Venatici , "in order that the rotations of the heavens should never cease." In past ages, whichever star held the position of Pole Star was worshipped as the star of that age and temples were built to them in ancient Egypt. Polaris is now the star of our own age. The planet, Uranus, was discovered one degree longitude away from this star. A good essay on Polaris by Lance Carlyle Carter can be read on this website: from p.453 of Star Names , Richard Hinckley Allen, 1889.

Phoenice was the early Greek name, borrowed from its constellation, for this "lovely northern light" and the "most practically useful star in the heavens"; but for many centuries it has been Stella Polaris, the Pole-star, or simply Polaris,— The Italian astronomer Riccioli's (1598–1671) Pollaris; this position seeming to be first recognized in literature by Dante when he wrote in the Paradiso: The mouth imagine of the horn That in the point beginneth of the axis Round about which the primal wheel revolves.

Euclid (circa 300 B.C.) said in his Phainomena: A star is visible between the Bears ( Ursa Major and Ursa Minor ), not changing its place, but always revolving upon itself; Hipparchos (circa 160-120 B.C.), that the pole was "in a vacant spot forming a quadrangle with three other stars," both of these calling this (Greek) Polos, the (Latin) Polus of Lucan (39-65A.D.), Ovid (43 B.C.-18?A.D.), and other classical Latins; and Euphratean observers had called their pole-star Pul, or Bil.

But, although other astronomical writers used these words for some individual star, there is no certainty as to which was intended, for it should be remembered that during many millenniums the polar point has gradually been approaching our pole-star, which 2000 years ago was far removed from it,— in Hipparchos' (circa 160-120 B.C.) time 12°24' away according to his own statement quoted by Marinus of Tyre and cited by the second-century Greek astronomer Ptolemy. Miss Clerke writes as to this: {p.454} "The entire millennium before the Christian era may count for an interregnum as regards Pole-stars.

Alpha (α) Draco ( Thuban ) had ceased to exercise that office; Alruccabah (Polaris) had not yet assumed it." Kochab (the beta, β, star of Ursa Minor ), and kappa (κ) of Draco , at different times in that epoch, may have been considered as this pole-star, the last a 4th-magnitude about 10° distant from the true pole; although the 5th-magnitude b, 4° away in Alexandrian-Greek astronomer Eratosthenes' (276?-196 B.C.) day, perhaps was intended. And this is not unlikely, as this inconspicuous object, for some reason, was sufficiently noteworthy among the Chinese to bear the title How Kung, the Empress. The (Greek) aei phanes, "ever visible," of the 5th-century Stobaeus may have referred to our Polaris, then about 7° distant from the pole.

The fact that the Polaris of his day did not exactly mark the pole was noted by Pytheas, the Greek astronomer and navigator of Massilia, the modern Marseilles, about 320 B.C.; and till this discovery the belief was prevalent that the heavenly pole was absolutely fixed. In none of the foregoing cases' does a single star seem to be mentioned as a guide in navigation; but as knowledge in this art increased, our alpha (α) took the place of its constellation as Stella Maris, a title that Saint Jerome, in his Onomasticon, applied to the Virgin Mary; there, however, with no marine, or stellar, connection. But a star, being always a symbol of sanctity, was peculiarly so of the holiest of women, so that this title of the chief star of heaven was adopted as one interpretation of her Jewish name Miriam. The 17th century German astronomer Bayer's la Tramontana (a classical name for a northern wind, a cold north wind in Italy, from "trans-montanus, 'of a mountain'".

The English word "tramontane" means "a person who lives beyond the mountains", "a foreigner; a stranger) was well known before his day, for Eden translated from the First Decade, printed in 1511, "cauled by the Italians Tramontana"; and Jehan de Mandeville ("syr Iohn Maundauile") more than a century before the discovery of our continent (America), in his statement of his belief in the sphericity of the earth, wrote of it as "the Sterre Transmontane, that is clept the Sterre of the See, that is unmevable, and that is toward the Northe, that we clepen the Lode Sterre." One derivation of this transmontane is from the fact that the nations along the Mediterranean saw the star beyond their northern mountain boundary; and the word appears in the popular saying, current among the Latin races, of a man's "losing his Tramontane" when one had lost his bearings. Another earlier and much more probable origin, however, is from a title for the constellation already alluded to.

Similarly the Finns know Polaris as Taehti, the Star at the Top of the Heavenly Mountain. Anglo-Saxons of the 10th century said that it was the Scip-steorra, the Ship-star; Eden, "cauled of the Spanyardes Nortes"; the 17th century German astronomer Bayer, Angel Stern, the {p.455} Pivot Star, and the Latin Navigatoria; while it was the Steering Star to early English navigators, who "knew no North, but when the Pole Star shone".

Andrew Marvell, strangely the common friend of John Milton and King Charles II, said: "By night the northern star their way directs;" and Thomas Moore wrote, in his Light of the Haram: "that star, on starry nights The seaman singles from the sky To steer his bark for ever by." Thus, as the leading star, it became the Loadstar, or Lodestar, of early English authors; Spenser saying: "The pilot can no loadstar see," and Shakespeare's Helena, in A Midsummer Night's Dream, tells Hermia "Your eyes are lodestars." Milton's Comus had the much quoted Our Star of Arcady, Or Tyrian Cynosure; and L'Allegro : The Cynosure of neighb'ring eyes,— a designation of Polaris which has everywhere become common; while Cinosura and Cynosura regularly appeared in scientific works of the 17th and 18th centuries; but this was one of the ancients' titles for the whole of Ursa Minor , and never, by them, limited to the lucida (brightest star in a constellation).

The Star of Arcady either referred to Arcadia, the earthly home of Kallisto (identified with Ursa Major ), or to Arcas, her son(identified with Ursa Minor ), transferred to the skies by his father Jove, when ignorantly about to slay his mother after her transformation. The poet, however, followed a common error in locating Arcas here, for he properly was identified with Bootes . The Chinese had several names for it,— Pih Keih; Ta Shin; Tien Hwang Ta Ti, the Great Imperial Ruler of Heaven, the circumpolar stars circling around it in homage, the whole forming the Purple Subtle Enclosure; and Ti or Ti Tso, the Emperor's Seat, this last also being borne by alpha (α) Hercules . And it was Tow Kwei, as with Ursa Major , from its square of stars, beta (β Merak ), gamma (γ Phecda ), zeta (ζ Mizar ), and eta (η Alkaid ). Its first use in navigation is ascribed to their emperor Hong Ti, or Hwang Ti, a grandson of Noah!

However this may be, it seems certain that some polar star, or constellation, has been used in China from remote antiquity. In earliest Northern India the star nearest the pole was known as Grahadhara, the Pivot of the Planets, representing the great god Dhruva, and the Persian astronomer Al Biruni (973-1048 A.D.) said that among the Hindus of his time it was Dhruva himself. It was an object of their worship, as our Polaris is to-day among the Mandaeans along the Tigris and lower Euphrates. The Arabs knew Polaris as Al Kiblah, "because it is the star least distant from the pole," although then 5° away, and helped them, in any strange location distant from an established place of worship, to know the points {p.457} of the compass and thus the direction of Mecca and its Ka'bah ( Kaaba ), towards which every good Muslim must turn his head in prayer.

They also called it Al Jadi, the Young He Goat, which subsequently degenerated to Juddah, as Niebuhr heard it a century ago, and known in Desert story as Giedi, the slayer of the dead man on the Bier of Ursa Major . Wetzstein says that in Damascus it is called Mismar, a Needle or Nail. As marking the north pole it bore the latter's title, Al Kutb al Shamaliyy, the Northern Axle, or Spindle, from Al Kutb, the Pin fixed in the under stone of a mill around which the upper stone turns; and this same thought later appeared in English poetry, as in Marlowe's History of Doctor Faustus, where he says of the stars that All jointly move upon one axletree Whose terminine is term'd the world's wide pole.

The Arabian astronomers knew it as Al Kaukab2 al Shamaliyy, [Allen notes: Kaukab is the same as the Assyrian and Chaldaean word Kakkab, the Hebrew Kohabh; this last also the fighting name of Bar Cochab, the Son of a Star, who was the leader of the second revolt of the Jews in 132-135, during the reign of Hadrian, his shekels bearing a star over a tetrastyle temple. The name was variously written, but correctly as Bar Coziba, from his birthplace.] the Star of the North, an appellation perhaps given by their nomad ancestors to beta (β Kochab ) as nearer the pole in their time. The 13th century Persian astronomical writer Al Kazwini mentioned the belief of the common people that a fixed contemplation of Al Kaukab would cure itching of the eyelids,— ophthalmia, then, as now, being the prevalent disease of the Desert.

The Alfonsine Tables of 1521 have Alrucaba et est Stella polaris sive Polus; and the 17th century German astronomer Bayer, Alruccabah seu Ruccabah Ismaelitis; but this was shared with the next star, as also with the constellation. The Turks know it as Yilduz, the Star par excellence; and have a story that its light was concealed for a time after their capture of Constantinople. Polaris is 1° 14' distant from the exact pole ( Wikipedia says 42′ away as of 2006), which lies on the straight line drawn from Polaris to zeta (ζ) Ursa Major ( Mizar ), and will continue in gradual approach to the pole till about the year 2095, when it will be only 26' 30" {p.458} away.

It will then recede in favor successively of gamma (γ), pi (π), zeta (ζ), nu (ν), and alpha (α) of Cepheus ( Alderamin ), alpha (α) and delta (δ) of the Swan ( Cygnus - Deneb Adige is alpha), and Wega ( Vega ) of the Lyre , when, marked by this last brilliant star, 11,500 years hence the pole will be about 50° distant from its present position and within 5° of Wega ( Vega ), which for 3000 years will serve as the pole-star of the then existing races of mankind.

The polar point will thence circle past iota (ι) and tau (τ) Hercules , theta (θ), iota (ι), and alpha (α) Draco , beta (β) Ursa Minor , and kappa (κ) Draco back to our alpha (α) again; the entire period being from 25,695 to 25,868 years, according to different calculations.1 Shakespeare did not know all this when he wrote in Julius Caesar : "constant as the Northern Star, Of whose true fixed and resting quality There is no fellow in the firmament." [ Star Names , Their Lore and Meaning, Richard Hinckley Allen, 1889]. The astrological influences of the constellation Ursa Minor Legend: According to some accounts this constellation, Ursa Minor , represents Arcas, son of Callisto and Jupiter (see Bootes and Ursa Major ). Other writers state that it is meant to represent Cynosura, one of the Nymphs of Crete who reared the infant Jupiter; the other, Helice, being Ursa Major.

[Robson * , p.65-66.] Influences: According to Ptolemy the bright stars are like Saturn and in some degree like Venus. It is said to give indifference and improvidence of spirit, and to lead to many troubles.

By the Kabalists it is associated with the Hebrew letter Tau and the 21st Tarot Trump "The Universe." [Robson * , p.66.] The astrological influences of the constellation Ursa Minor given by Manilius: "Now where heaven reaches its culmination in the shining Bears ( Ursa Major and Ursa Minor ), which from the summit of the sky look down on all the stars and know no setting and, shifting their opposed stations about the same high point, set sky and stars in rotation, from there an insubstantial axis runs down through the wintry air and controls the universe, keeping it pivoted at opposite poles: it forms the middle about which the starry sphere revolves and wheels its heavenly flight, but is itself without motion and, drawn straight through the empty spaces of the great sky to the two Bears and through the very globe of the Earth, stands fixed, since the entire atmosphere ever revolves in a circle, and every part of the whole rotates to the place from which it once began, that which is in the middle, about which all moves, so insubstantial that it cannot turn round upon itself or even submit to motion or spin in circular fashion, this men have called the axis, since, motionless

 itself, it yet sees everything spinning about it.

"The top of the axis is occupied by constellations well known to hapless mariners, guiding them over the measureless deep in their search for gain. Helice ( Ursa Major ), the greater, describes the greater arc; it is marked by seven stars which vie with each other under its guidance the ships of Greece set sail to cross the seas. "Cynosura ( Ursa Minor ) is small and wheels round in a narrow circle, less in brightness as it is in size, but in the judgment of the Tyrians it excels the larger bear. "Carthaginians count it the surer-guide when at sea they make for unseen shores. They are not set face to face: each with its muzzle points at the other's tail and follows one that follows it. Sprawling between them and embracing each the Dragon ( Draco ) separates and surrounds them with its glowing stars lest they ever meet or leave their stations." [ Astronomica , Manilius, 1st century AD, p.27]. The astrological influences of the star Polaris Of the nature of Saturn and Venus. It causes much sickness, trouble, loss of fortune, disgrace and great affliction, and may give legacies and inheritances attended by much evil.

The Arabs were of the opinion that the contemplation of Polaris cured ophthalmia. [Robson * , p.185.] The pole star, Polaris, is the main star of "the small Bear", situated on the tail, has a Saturn nature, combined with qualities of Sun and Venus. It might seem strange to include this fixed star here, as its latitude is about 60° and therefore placed far outside of the ecliptic in which the planets move. Measured on the ecliptic, it is situated closely conjunct with Alpha Orionis, Betelgeuze , the main star of Orion . The Chinese considered the Pole Star as "the great honorable Lord of the Heavens". Other races too had high admiration for it, and one can draw the conclusion that, in a relevant position in the natal chart, it will give spiritual powers to the bearer, and he will be highly respected. The Pole Star serves as a guide and indicator. If it is conjunct with planets in the angles, the native will have a good sense of discretion and is able to follow "his instinct". He clearly recognizes his aims, and will pursue and achieve them.

[ Fixed Stars and Their Interpretation , Elsbeth Ebertin, 1928, p.35-36.] With Sun: Many troubles and evils. [Robson * , p.185.] With Moon: Hatred of the vulgar, ill-will of women and danger from thieves. [Robson * , p.185.] References: Sky Tellers - The Myths, the Magic, and the Mysteries of the Universe About Polaris How Do I Find Polaris? Polaris is located in the constellation Ursa Minor, which contains the group of stars that make up the “Little Dipper.” Polaris is the star in the end of the Little Dipper handle. Often, however, the Little Dipper is not very bright and can be challenging to find. Polaris is easiest to find by locating the seven stars of the Big Dipper in the constellation Ursa Major, or Big Bear. These stars form a small bowl with a long handle. Follow the stars of the Big Dipper from the handle to the side of the bowl, to the bowl bottom, and up the other side; the two stars forming the second side, Dubhe and Merak, point to Polaris.

Take the distance between Dubhe and Merak; Polaris is the bright star that sits about five times that distance away. Polaris actually is part of a binary (two) star system. Of the stars nearest to our Sun, about half are known to be in multiple systems (two or more stars). Between 5 and 10 percent of the stars we can observe are “visible binaries” — the star companions can be observed with a telescope. These systems reveal a great deal of information. Because of their interactions, astronomers can determine the gravitational pull exerted by the companions and calculate the mass of the individual stars. Polaris is helpful to astronomers in another way; it is a variable star. Polaris pulsates, a change we detect as a pattern of dimming and brightening. This pulsation helps astronomers calculate celestial distances. Why Doesn't Polaris Move? Polaris is very distant from Earth, and located in a position very near Earth's north celestial pole. Earth rotates once a day on its axis, an imaginary line that passes through Earth from its north pole to its south pole. If that imaginary line — the axis — is projected into space above the north pole, it points to Earth's north celestial pole.

As the Earth spins on its axis, it also “spins around” the north celestial pole. Polaris, located almost exactly at the north celestial pole, the center of spin, stays in the same place, while stars farther away from the north celestial pole can be seen to move in a wider circle around Polaris as viewed from Earth during its daily rotation. Polaris actually lies just a short distance away from where Earth's axis points. Polaris is located about 1 degree off to the side of the north celestial pole, so Polaris does move a little, tracing a very small arc in the night sky, around which the other visible stars make wider circles. This picture of the night sky above Hawaii was taken by leaving the camera shutter open for a long time. The picture captures the apparent movement of the stars caused by Earth's rotation on its axis. Polaris is the star in the center of the star field; it shows essentially no movement. Earth's axis points almost directly to Polaris, so this star is observed to show the least movement. The other stars appear to trace arcs of movement because of Earth's spin on its axis. Photograph by Richard J.

Wainscoat Polaris | Constellation Guide Constellation Guide Constellations: A Guide to the Night Sky Polaris by admin Here are some of the things to see in April: by admin Here are some of the things to see in April: by admin The Ursids, or Ursid meteor shower, are an annual meteor shower that coincides with the winter solstice. The Ursids occur from December 17 to 25 and peak just before Christmas, around December 22, with a zenithal hourly rate of 10 meteors per hour. The meteor shower was named for its radiant point, or apparent point … [Read more…] by admin Canopus, Alpha Carinae, is the brightest star in Carina constellation and the second brightest star in the night sky. Canopus is fainter only than Sirius. The star is a supergiant or bright giant, yellowish-white in colour, with an apparent magnitude of -0.72. It is located at a distance of 310 light years from Earth.

It … [Read more…] by admin Capella, also known as Alpha Aurigae or the Goat Star, is the brightest star in Auriga and the sixth brightest star in the sky. The only stars in the northern celestial hemisphere brighter than Capella are Arcturus in Boötes constellation and Vega in Lyra. The only other star visible from northern latitudes that is brighter … [Read more…] by admin The Northern Cross is a prominent asterism formed by the brightest stars in the constellation Cygnus. by admin Polaris, also known as the North Star, Alpha Ursae Minoris or Star of Arcady, is the brightest star in Ursa Minor constellation. Polaris is notable for currently being the closest bright star to the North Celestial Pole. The pole marks true north, which makes the North Star important in navigation, as the star’s elevation above … [Read more…] Brilliant Star Vega Lights Up July Nights Brilliant Star Vega Lights Up July Nights By Joe Rao, SPACE.com Skywatching Columnist | July 22, 2011 05:05pm ET MORE Look directly overhead to find the star Vega in the constellation Lyra. North is at the top of this sky map.

Credit: Starry Night Software Standing almost directly overhead around midnight on July nights is the brilliant bluish-white star, Vega, in the constellation of Lyra, the Harp. It's the fifth brightest star in the entire sky and the third brightest visible from mid-northern latitudes, behind Sirius and Arcturus. Also, as seen from mid-northern latitudes such as New York or Madrid, Vega goes below the horizon for only about seven hours a day, meaning that you can see it on any night of the year. The sky map of Vega here shows how the star appears in relation to constellations and other stars. Farther south, Vega is below the horizon for an even longer interval of time. Conversely, for Alaska, central and northern Canada, as well as central and northern Europe, Vega never sets and is readily visible on any night of the year. Popular misconception As a young boy I used to spend my summers at Long Island's Atlantic Beach.

On clear nights, my Uncle Bob would point to Vega and tell me that it was "the North Star, the brightest star in the sky." Of course, he was wrong: the North Star is Polaris at the end of the tail of Ursa Minor, the Little Bear. Even today the idea that the North Star is the brightest star in the sky continues to be a popular misconception. [ Stunning Daily Photos of Stars and Galaxies ] Vega is the brightest of the three stars forming the large " Summer Triangle " consisting of Vega, Altair and Deneb. It is located 25 light-years away, has a diameter approximately three times that of our sun and is 58 times more luminous. In January 2002, astronomers at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., announced that features observed in a cloud of dust swirling around Vega may in fact, be the signatures of an unseen planet in an eccentric orbit around the star. Getting the name wrong Observations of Vega in 1983 with the Infrared Astronomy Satellite provided the first evidence for large dust particles around another star , probably debris related to the formation of planets.

This discovery likely inspired Carl Sagan to place a planet orbiting Vega in his novel "Contact." "Contact" was also made into a 1997 American film, directed by Robert Zemeckis. I personally enjoyed it for the most part, except for one thing; the mispronunciation of Vega. [ What Makes an Alien Encounter Movie Believable? ] Vega is correctly pronounced "Vee-ga." But between 1971 and 1977, the Chevrolet division of General Motors produced a lightweight four-cylinder automobile that was christened after Vega. The car's name was marketed as being pronounced "Vay-ga." For years thereafter, whenever I gave planetarium shows or lectured under the real sky, I would remind my audience that Vee-ga was a star, but Vay-ga was a car. Unfortunately, it appears that the latter pronunciation carried-over two decades later into the production of the film "Contact." Today I tell people that if the film's protagonist, Dr.

Eleanor "Ellie" Arroway was a real person, then as an astronomer she would have referred to the strong extraterrestrial signal as emanating from the star Vee-ga and not from the car Vay-ga. But then, that's Hollywood. Vega also holds a rather unique place in the annals of astronomy as being the first star ever to be photographed. The historic photograph was made using the daguerreotype process at Harvard Observatory on the night of July 16-17, 1850. A 15-inch refractor was used, but nonetheless it still took an exposure of 100 seconds for Vega's image to register. The lyre Officially, Lyra is a lyre — a stringed instrument of the harp family used to accompany a singer or reader of poetry, especially in ancient Greece. In Greek mythology, Lyra was associated with the myth of Orpheus, the musician who was killed by the Bacchantes. After his death, his lyre was thrown into the river. Zeus sent an eagle to retrieve the lyre, and ordered both of them to be placed in the sky.

This is why Lyra is often represented on star maps as a vulture or an eagle carrying a lyre, either enclosed in its wings, or in its beak. Six stars form a combined geometric pattern of a parallelogram and an equal-sided triangle attached at its northern corner. Vega gleams at the western point of the triangle. In his classic book, "The Stars — A New Way to See Them," author H.A. Rey commented that Lyra better resembled a two-stringed zither than a traditional lyre. But there are other interesting sights to explore here. Epsilon Lyrae, at the northern point of the little triangle where Vega is located, is known as the "double-double" star. Good eyesight reveals Epsilon is really a close pair of stars. Binoculars readily separate the two, while a moderately large telescope shows each one divided again into two stars. [ Telescopes for Beginners ] The star Sheliak is one of the two that forms the southern side of the parallelogram and appears to diminish by half of its normal brightness about every 13 days when it's eclipsed by a darker companion star.

Between this winking star and its neighbor, Sulafat is the famous Ring Nebula, faintly glowing like a ghostly doughnut or a cosmic smoke ring. Visible only in large telescopes, it appears as an oval ring around a star. Millions of years ago, this star exploded, hurling out great masses of gas. We see the star now through the thin part of this gaseous envelope. One final point. Thanks to precession, the wobbling motion of the earth's axis, in 12,000 years, our north polar axis will be pointing in the general direction of Vega and it will indeed officially become the North Star. My Uncle Bob passed away in 2009, but I'm sure that piece of news would have made him very happy. Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and other publications, and he is also an on-camera meteorologist for News 12 Westchester, New York.

The mystery of the North Star: Astronomers baffled to find Polaris is getting BRIGHTER | Daily Mail Online The mystery of the North Star: Astronomers baffled to find Polaris is getting BRIGHTER Team found that Polaris is 2.5 times brighter today than in 137CE Experts say find is 'entirely unexpected' Astronomers have discovered that Polaris, the north star, is getting brighter. They say the star has suddenly reversed two decades of dimming. It is expanding at more than 100 times the rate they expected - and nobody is sure why. Is Polaris getting brighter? Stars appear to rotate around Polaris, the north star, in this long exposure picture taken near the 4-meter telescope dome at Kitt Peak National Observatory near Tucson, Arizona. The image is composed of 114 30-second exposures of the night sky combined to make the equivalent of a nearly one hour exposure in which the earth's rotation causes the stars to appear to move across the night sky. THE NORTH STAR Polaris, also known as the North Star, Northern Star or Pole Star, is the brightest star in the constellation Ursa Minor.

Historically it has been used to guide travellers, and is very close to the north celestial pole, making it the current northern pole star. Recent papers calculate the distance to Polaris at about 434 light-years, although some suggest it may be 30% closer which. A team led by Scott Engle of Villanova University in Pennsylvania recalibrated historic measurements of Polaris by Ptolemy in 137 C.E., the Persian astronomer Al-Sufi in 964 C.E., and others. They investigated the fluctuations of the star over the course of several years, combing through historical records and utilising the Hubble Space Telescope. The team found that Polaris is 2.5 times brighter today than in Ptolemy's time, which they say is a remarkable rate of change. RELATED ARTICLES Share this article Share 'If they are real, these changes are 100 times larger than predicted by current theories of stellar evolution,' says Villanova astronomer Edward Guinan.

The team's data also hint that the star's cyclic 4-day variation in brightness, although still weak, is once again growing more robust--but no one knows what's driving these flutterings or how long they will last. Engle and his team began to research the star around the beginning of 2000, when they found that the dropping brightness was on the rise again. Pinpointing Polaris: Researchers say it is getting brighter far more quickly than they expected after reversing its dimming 'It was unexpected to find,' Engle told SPACE.com.'It started increasing rather rapidly.' 'Polaris is arguably the best-known star in the Northern Hemisphere, since it lies within a degree of the North Celestial Pole,' the researchers wrote. 'For much of human history, Polaris was highly regarded for its unchanging nature. 'However, we now know that Polaris is a Cepheid variable, undergoing ultra-low-amplitude pulsations. 'Thirty years ago, a paper in the Astrophysical Journal by A. Arellano Ferro announced that the amplitude of these pulsations was diminishing. 'This behavior was confirmed, and it was believed that soon enough Polaris would no longer be a Cepheid variable.

Star Trails above Beccles, with Polaris in the centre 'We started photometrically monitoring Polaris in 1999 and discovered that the amplitude of pulsations had reached a minimum and was now, in fact, growing again. 'It was while gathering historic photometry for the amplitude study that we noticed the published magnitudes of Polaris were systematically fainter, the further back in time the data went. 'This is an entirely unexpected behavior for a Cepheid variable, and one that we wanted to investigate further. Engle presented the results of his research in a poster session at the American Astronomical Society meeting in Washington.

Question: Polaris is the brightest star in which constellation?
Answer: URSA MINOR