Betelgeuse - Alpha Orionis | Constellation Guide Constellation Guide Constellations: A Guide to the Night Sky Betelgeuse by admin Betelgeuse, Alpha Orionis, is the second brightest star in Orion constellation and the ninth brightest star in the sky. It is a supergiant star, distinctly red in colour, located at an approximate distance of 643 light years from Earth. It is an evolved star, one expected to explode as a supernova in a relatively near future. Betelgeuse is a large, bright, massive star easily found in the sky in the winter months because it is part of a familiar pattern formed by the celestial Hunter. The red supergiant marks one of Orion ‘s shoulders, while the hot, bright giant Bellatrix, Gamma Orionis, marks the other. Betelgeuse is a variable star and, as its brightness changes, the star has been known to outshine the constellation’s brightest star, the blue supergiant Rigel, Beta Orionis.

Alpha Orionis’ traditional name, Betelgeuse, originated in the Arabic phrase Yad al-Jauzā’, meaning “the shoulder of the central one” or “the hand of Orion,” referring to the star’s position in the constellation. The phrase al-Jauzā’ is the traditional Arabic name for Orion constellation . It can be loosely translated as “the central one,” referring to a mysterious woman. The modern Arabic name for the constellation is al-Jabbār, meaning “the giant.” With the phrase Yad al-Jauzā’, Medieval translators misread the Arabic character for Y as B, which resulted in a mistranslation into “armpit of the giant.” The name Betelgeuse can be pronounced /ˈbiːtəldʒuːs/, /ˈbiːtəldʒuːz/, or /ˈbɛtəldʒuːz/. The original pronunciation is uncertain. Position of Betelgeuse in the constellation of Orion. Image: Akira Fujii Betelgeuse and Bellatrix mark the two shoulders of Orion, the Hunter . Betelgeuse, marking the right shoulder, lies in the upper left corner of the constellation from our point view.

It is one of the largest and most luminous stars known. Placed at the centre of our solar system, Alpha Orionis would extend beyond the asteroid belt, all the way to the orbit of Jupiter and possibly beyond. Betelgeuse belongs to the spectral class M2Iab. The M refers to the star’s colour, red, and the ‘Iab’ suffix indicates that the star is an intermediate luminosity supergiant. It has an absolute magnitude of roughly -6.02. The star’s mass is uncertain, but estimates range from 7.7 to 20 times that of the Sun. As a result of its high mass, Betelgeuse has evolved quickly and, even though it is less than than 10 million years old, it is nearing the end of its life cycle. The star is believed to have an average luminosity about 120,000 times that of the Sun. Betelgeuse is classified as a semi-regular variable star. Its apparent magnitude varies from 0.2 to 1.2 over a period of about 400 days, which is the widest magnitude range for a first magnitude star.

Because it varies in magnitude, Betelgeuse occasionally surpasses Procyon in Canis Minor in brightness and becomes the seventh brightest star in the sky. When at its brightest, Betelgeuse outshines Rigel, the brightest star in Orion , and becomes the sixth brightest star in the sky. At its faintest, it drops below Deneb , the brightest star in Cygnus , and shares the position of the 20th brightest star with Mimosa, Beta Crucis, located in Crux constellation and one of the stars that form the Southern Cross . Betelgeuse is a pulsating red supergiant showing low-amplitude variations and periods of stable brightness. The star’s pulsations result in its absolute magnitude varying from -5.27 to -6.27. As its outer layers expand and contract, the surface increases and decreases, and the temperatures rises and falls. Betelgeuse pulsates because it has an unstable stellar atmosphere. When it contracts, it absorbs more of the energy that passes through it. As a result, its atmosphere heats up and expands. When the star expands, the atmosphere becomes less dense and cools down, which leads to another period of contraction.

This collage shows the Orion constellation in the sky (Betelgeuse is identified by the marker), a zoom towards Betelgeuse, and the sharpest ever image of this supergiant star, which was obtained with NACO on ESO’s Very Large Telescope. Image: ESO, P.Kervella, Digitized Sky Survey 2 and A. Fujii There are several cycles to the star’s pulsations, with short-term variations of roughly 150 to 300 days, and longer, cyclic variations over a period of about 5.7 years. As a result of the star’s variability, limb darkening, angular diameter that tends to vary with wavelength, and the star’s tendency to occasionally change shape, many of Betelgeuse’s properties are still uncertain. Because the star is rapidly losing mass, its surface is obscured by a large envelope of ejected material, approximately 250 times larger than the star itself, which makes measurements even more difficult. In 1985, two close companions were discovered in orbit around Betelgeuse, but have not been confirmed by research in the years since.

Betelgeuse is easy to find in the sky because it is part of a prominent winter constellation, Orion the Hunter . From mid-September to mid-March, the star is visible from almost any location on the globe, with the exception of those south of 82°S. For observers in the northern hemisphere, Betelgeuse rises in the east just after sunset in January. In March, it is due south early in the evening. By May, the star only briefly shows up on the western horizon after sunset. In the early summer, it travels behind the Sun and can’t be seen. A few months later, it can be seen appearing on the eastern horizon just before dawn. In June and July, Betelgeuse can’t be seen at night at all, only using a telescope in daylight. Supernova Betelgeuse has reached a late stage of evolution and is expected to end its life in a supernova explosion at some point within the next million years. The red supergiant will most likely explode as a Type II supernova.

The supernova may brighten to a visual magnitude of -12 over a couple of weeks, which would make it outshine the Moon, cast shadows in the night, and be visible in daylight. The supernova would stay at that intensity for two to three months before dimming. The last bright supernova, SN 1987A, was visible to the naked eye even though the progenitor star wasn’t even in our galaxy, but in the nearby Large Magellanic Cloud in Dorado constellation , roughly 168,000 light years away from the solar system. While Betelgeuse is far too distant to do any damage to Earth, when it explodes, it will certainly give us a very bright spectacle in the sky. Earth will most likely not be affected by the explosion because Betelgeuse’s rotational axis is not pointed toward our planet and the gamma ray burst sent by the supernova will most likely not cause any damage to our ecosystems. Neutrinos and other forms of radiation will not reach us until 600 years after the explosion and will not affect terrestrial life. Supernovae generally must be within 25 light years to cause any significant damage to Earth.

At 643 light years, Betelgeuse is more than 25 times that distance. Betelgeuse has evolved off the main sequence and has expanded and cooled to become a red supergiant. Even though it is a relatively young star, it has likely used up the hydrogen at its core, which is causing the star to contract, its temperature to rise, and its density to increase. Consequently, Betelgeuse has started fusing helium into carbon and oxygen. At some point, the star will collapse and explode. Most likely, it will leave behind a neutron star roughly 20 kilometres in diameter. Mass is a key factor when predicting how a star will end its life. The exact mass of Betelgeuse is uncertain, but most astronomers who have investigated the star agree that it has more than 10 solar masses. If its mass and rotation speed are sufficient, Alpha Orionis may even evolve into a yellow hypergiant or a luminous blue variable before the supernova event. FACTS Betelgeuse is part of two familiar winter asterisms. It marks the upper right vertex of the Winter Triangle .

The stars of the Winter Triangle and the Winter Hexagon The other two stars that form the Winter Triangle are Procyon in Canis Minor and Sirius in Canis Major . Betelgeuse also lies at the centre of the Winter Hexagon , formed by Sirius , Procyon, Pollux in Gemini , Capella in Auriga , Aldebaran in Taurus , and Rigel in Orion constellation . In 2013, scientists said that Betelgeuse would likely crash into a “cosmic wall” of interstellar dust in several thousand years. The star’s solar wind is expected to reach the wall in about 5,000 years and the star itself is expected to crash into the bar roughly 12,500 years after that. The bar is thought to be either a linear filament linked to the Milky Way’s magnetic field or the edge of an interstellar cloud lit by Betelgeuse. Alpha Orionis originated in the Orion OB1 Association, a group of stars whose members include the stars of Orion’s Belt , which share the same proper motion and velocity through space.

The red supergiant is believed to have changed its course and motion through space at some point because its projected pathway does not seem to intersect with any star forming region. The most likely scenario is that it is a runaway member of the Orion OB1 Association, formed some 10-12 million years ago in a molecular cloud in Orion . This picture of the dramatic nebula around the bright red supergiant star Betelgeuse was created from images taken with the VISIR infrared camera on ESO’s Very Large Telescope (VLT). This structure, resembling flames emanating from the star, forms because the behemoth is shedding its material into space. The earlier NACO observations of the plumes are reproduced in the central disc. The small red circle in the middle has a diameter about four and half times that of the Earth’s orbit and represents the location of Betelgeuse’s visible surface. The black disc corresponds to a very bright part of the image that was masked to allow the fainter nebula to be seen. Image: ESO, VLT, P. Kervella Betelgeuse moves through space at a speed of 30 km/s.

As a result, its stellar wind has created a bow shock more than 4 light years wide. The wind is ejecting vast amounts of gas into space at a rate of 17 km/s, heating up the material around the star. Consequently, it is visible in infrared wavelengths. The bow shock was first imaged in 1997. Its cometary structure is believed to be at least one parsec wide if the star’s estimated distance of 643 light years from the solar system is accurate. The bow shock is estimated to be less than 30,000 years old. Alpha Orionis is the brightest near-infrared source in the sky. It has a J band magnitude of -2.99. Only 13 percent of the star’s energy is emitted in visible light. The star’s variability was first noted by John Herschel in 1836. He published his notes in Outlines of Astronomy. Over the next four years, Herschel noticed that Betelgeuse was showing considerable changes in magnitude. In October 1837, it outshone Rigel, the brightest star in Orion , and did it again in November 1839.

The variations in brightness may have been the reason why Johann Bayer gave Betelgeuse the designation Alpha in his Uranometria, published in 1603, even though it is usually not as bright as Rigel, designated Beta Orionis. Betelgeuse was the first star other than the Sun to have its disk imaged in optical and infrared wavelengths, by John E. Baldwin and his colleagues at the Cavendish Astrophysics Group. Alpha Orionis is believed to have started its life as a hot, blue class O star some 10 million years ago. The star had an initial mass about 18-19 times that of the Sun. The spelling of the name Betelgeuse did not become universal until the early 20th century. Before that, the star’s name was spelled Betelgeux or Betelgeuze. Photo taken by Rogelio Bernal Andreo in October 2010 of the Orion constellation showing the surrounding nebulas of the Orion Molecular Cloud complex. Also captured is the red supergiant Betelgeuse (top left) and the famous belt of Orion composed of the OB stars Altitak, Alnilam and Mintaka.

To the bottom right can be found the star Rigel. The red crescent shape is Barnard’s Loop. The photograph appeared as the Astronomy Picture of the Day on October 23, 2010. Image: Rogelio Bernal Andreo Betelgeuse has had many different names across the cultures, including the Sanskrit Bahu, reflecting the Hindu view of the Orion constellation as a running stag or antelope, the Persian Bašn (“the Arm”), and Coptic Klaria (“an Armlet”). The Chinese knew the star as Shēnxiùsì, the Fourth Star of the constellation of Three Stars, referring to the stars forming Orion ‘s girdle. The constellation was later expanded to include ten stars. In Japan, Alpha Orionis was known as Heike-boshi, referring to the Heike clan, which adopted the star and its red colour as its symbol. Tahitian observers considered Betelgeuse to be one of the pillars holding the sky. They knew the star as Anâ-varu. In Hawaii, the star was known as Kaulua-koko, which means “brilliant red star.” In cultures across the Americas, the star is often seen as a severed limb.

The Taulipang of Brazil called the constellation Zililkawai, and it represented a hero whose leg was severed by his wife. The star’s blinking light represented the severing of the leg. The Lakota people saw it as a chief with a severed arm. In northern Australia, the Wardaman people called Betelgeuse Ya-jungin, meaning “Owl Eyes Flicking.” In South Africa, the star represented a lion stalking three zebras, marked by Alnilam, Alnitak, and Mintaka, the stars of Orion’s Belt . In Macedonian legend, Betelgeuse was associated with Orach, “the ploughman,” while the rest of Orion constellation represented a plough with oxen. Image of the supergiant star Betelgeuse obtained with the NACO adaptive optics instrument on ESO’s Very Large Telescope. The use of NACO combined with a so-called “lucky imaging” technique, allowed the astronomers to obtain the sharpest ever image of Betelgeuse, even with Earth’s turbulent, image-distorting atmosphere in the way.

The resolution is as fine as 37 milliarcseconds, which is roughly the size of a tennis ball on the International Space Station (ISS), as seen from the ground. The image is based on data obtained in the near-infrared, through different filters. The field of view is about half an arcsecond wide, North is up, East is left. Image: ESO/P. Kervella Betelgeuse has also been mentioned in numerous films, television shows, novels, and other works of fiction. In Tim Burton’s 1988 feature Beetlejuice, an undead bio-exorcist played by Michael Keaton shares the star’s name. In The Hitchhiker’s Guide to the Galaxy, Betelgeuse was the home system of Zaphod Beeblebrox, the Galactic President. In The Cthulhu Mythos, the star is the home of the Elder Gods. Betelgeuse has also been notably mentioned in Jean Louis De Esque’s poetic work Betelguese, a trip through hell (1908), Muhammad Barker’s Tékumel novels and games, Philip K.

Dick’s short stories “Tony and the Beetles” (1953) and “Shell Game” (1954), Kurt Vonnegut, Jr.’s novel The Sirens of Titan (1959), Pierre Boulle’s novel Planet of the Apes (1963), Gérard Klein’s Le Gambit des Etoiles (1958), Frank Herbert’s Dune series (as Bela Tegeuse), Isaac Asimov’s The Robots of Dawn (1983), Robert J. Sawyer’s Calculating God (2000), and Jeffrey Carver’s From a Changeling Star (1989). Betelgeuse is also mentioned in the games BattleTech, Star Control II, Frontier: Elite II, and Frontier: First Encounters. Size The size of Betelgeuse is difficult to determine, but its diameter is believed to change from 550 to 920 times the Sun’s diameter. The star is large enough that it reveals a disk when seen in the best telescopes.

This artist’s impression shows the supergiant star Betelgeuse as it was revealed thanks to different state-of-the-art techniques on ESO’s Very Large Telescope, which allowed two independent teams of astronomers to obtain the sharpest ever views of the supergiant star Betelgeuse. They show that the star has a vast plume of gas almost as large as our Solar System and a gigantic bubble boiling on its surface. These discoveries provide important clues to help explain how these mammoths shed material at such a tremendous rate. The scale in units of the radius of Betelgeuse as well as a comparison with the Solar System is also provided. Image: ESO/L. Calçada The star’s diameter was measured in 2000 using the Infrared Spatial Interferometer (ISI) and the calculations yielded a radius of 3.6 astronomical units. In June 2009, Charles Townes, Nobel Laureate and inventor of the laser, announced his discovery that Betelgeuse had shrunk by 15 percent since 1993, without losing brightness. The contraction was likely a result of shell activity in Betelgeuse’s extended atmosphere.

Astronomers have pinpointed at least six shells around the star. Betelgeuse was observed ejecting a vast amount of gas in July 2009, with distances roughly equalling 30 astronomical units. Alpha Orionis was the second star after the Sun to have the angular size of its photosphere measured. It was measured on December 13, 1920 by Albert Michelson and Francis Pease at Mount Wilson Observatory. They measured the star’s angular diameter at 0.047”, which translated into a diameter of 2.58 astronomical units. However, these numbers are uncertain because of limb darkenining and measurement errors. Estimates over the years have ranged from 0.042 to 0.069 arcseconds and a projected radius of the stellar disk between 1.2 and 8.9 astronomical units. The star’s diameter is difficult to determine for several reasons. First, because Alpha Orionis is a pulsating variable, which means that its diameter changes over time. Second, because it is difficult to determine a definable ‘edge’ of the star because limb darkening causes its optical emissions to vary in colour.

Third, because it is also hard to define the star’s photosphere because it is surrounded by a a thick gaseous envelope made up of material ejected by the star which absorbs and emits light. As a result, the measured diameter changes depending on the wavelength used to measure it. Comparison of size of Betelgeuse (largest dull-red sphere inside Jupiter’s orbit) and R Doradus (red sphere shown inside Earth’s orbit) together with the orbits of Mars, Venus and Mercury and the stars Rigel and Aldebaran from Image:1e10m comparison Rigel, Aldebaran, and smaller – antialiased no transparency.png, to scale. The faint yellow sphere centred on the Sun has a radius of one light-minute. The yellow ellipses represent the orbits of each planet. Image: Paul Stansifer and 84user at wikipedia.org Betelgeuse was once thought to have the largest angular diameter of any star. However, after a team of astronomers measured the diameter of R Doradus at 57.0 mas. in 1997, the star lost this distinction.

It is now considered to be in third place even though R Doradus, a Mira variable located in Dorado constellation and much closer to Earth at less than 200 light years, has a diameter only about a third that of Alpha Orionis. Betelgeuse’s estimated radius is about 5.5 astronomical units, which makes the star around 1,180 times larger than the Sun. With the observed contraction, the star’s radius has shortened to 4.6 astronomical units. Distance Betelgeuse lies at a distance of 643 light years or 197 parsecs from Earth. Earlier estimates of the star’s distance were 430 light years (131 parsecs) in 1997, and 520 light years (152 parsecs) in 2007. The star’s exact distance is uncertain because direct parallax measurement results in a distance of about 495 light years, while the parallax using the natural radio emission yields about 640 light years. Sometimes the middle distance – 570 light years – is cited.

In 2008, Graham Harper and colleagues used the Very Large Array (VLA) and came up with radio data that yielded a distance of 643 light years. Colour Alpha Orionis has a colour index (B–V) of 1.85, which makes it a very red star. This image is a colour composite made from exposures from the Digitized Sky Survey 2 (DSS 2). The field of view is approximately 2.0 x 1.5 degrees. Image: ESO/Digitized Sky Survey 2 The star’s photosphere has an extended atmosphere. As a result of being surrounded by a thick envelope of gas, the star’s extended atmosphere exhibits strong lines of emission rather than absorption. It has been known to move away and toward the star as a result of radial velocity fluctuations in the photosphere. The star’s red colour has been documented since antiquity. The Greek astronomer Ptolemy described it as ruddy (ὑπόκιρρος – hypókirros) in the 2nd century. Three centuries before Ptolemy’s observations, Chinese astronomers noted that the star had a yellow coloration.

This indicates that Betelgeuse may have been a yellow supergiant just before the beginning of the common era. Temperature The temperature of the star’s surface is estimated to be between 3,140 and 3,641 K. The estimated temperature of the star’s atmosphere is around 3,450 K. The gas around the star gradually cools as it expands away from the star.

Betelgeuse – Alpha Orionis Coordinates: 05h 55m 10.3053s (right ascension), +07°24’25.426” (declination) Spectral class: M2Iab Apparent magnitude (visible spectrum): 0.42 (0.3 to 1.2) Apparent magnitude: (J band): -2.99 ± 0.10 Absolute magnitude: -6.02 Distance: 643 ± 146 light years (197 ± 45 parsecs) Variable type: SR c (semi-regular variable) Mass: 7.7 – 20 solar masses Radius: 950 – 1,200 solar radii Luminosity: 120,000 ± 30,000 solar luminosities Temperature: 3,140 – 3,641 K Age: 7.3 million years Pronunciation: /ˈbiːtəldʒuːs/, /ˈbiːtəldʒuːz/, or /ˈbɛtəldʒuː

z/ Designations: Betelgeuse, Alpha Orionis, α Orionis, 58 Orionis, HR 2061, BD +7° 1055, HD 39801, FK5 224, HIP 27989, SAO 113271, GC 7451, CCDM J05552+0724AP, AAVSO 0549+07 VIDEO Betelgeuse will explode someday | Brightest Stars | EarthSky Betelgeuse will explode someday By Larry Sessions in Brightest Stars | December 25, 2016 Someday, the star Betelgeuse will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion.

Someday … but probably not soon. Red Betelgeuse, also known as Alpha Orionis, is the ninth-brightest star in the night sky and second-brightest in the constellation of Orion. Photo taken February 18, 2014 by Thomas Wildoner . As the year turns, or on some January or February evening, come to know the red star Betelgeuse in the constellation Orion. It’s not only one of Orion’s brightest stars. It’s also a star that astronomers know will one day explode as a supernova. And by one estimate, it’s only 430 light-years away! Follow the links below to learn more about Betelgeuse and its explosive destiny. Celebrate 2017 with an awesome EarthSky moon calendar! Betelgeuse imaged in ultraviolet light by the Hubble Space Telescope and subsequently enhanced by NASA. The bright white spot is likely one of this star’s poles. Image via NASA/ESA. View larger. | Thomas Wildoner captured these before-and-after images of the supernova that erupted in January 2014, in the galaxy M82. See the supernova?

Astronomers sometimes say that a supernova can outshine the galaxy in which it resides. This photo makes me believe it! Read more about the supernova in M82. Betelgeuse will explode someday Betelgeuse lies some 430 light-years from Earth. (Note: determining distances, especially to red supergiant stars, is a vexing problem in Astronomy. Estimates vary and are often revised, with some as high as 650 light-years.) Yet it’s already one of the brightest stars in Earth’s sky. The reason is that Betelgeuse is a supergiant star. It is intrinsically very brilliant. Such brilliance comes at a price, however. Betelgeuse is one of the most famous stars in the sky because it’s due to explode someday. Betelgeuse’s enormous energy requires that the fuel be expended quickly (relatively speaking), and in fact Betelgeuse is now near the end of its lifetime. Someday soon (astronomically speaking), it will run out of fuel, collapse under its own weight, and then rebound in a spectacular supernova explosion.

When this happens, Betelgeuse will brighten enormously for a few weeks or months, perhaps as bright as the full moon and visible in broad daylight. When will it happen? Probably not in our lifetimes. But, in fact, no one really knows. It could be tomorrow or a million years in the future. Images of closest supernova in years, in galaxy M82 Cool image, but we won’t see this from Earth when Betelgeuse goes supernova sometime in the next thousand – or million – years. Image via Geekosystem Will Betelgeuse become a second sun? Short answer: no. That rumor was flying around in 2012. Remember 2012? The year the world was supposed to end? Anyway, when it does go supernova, Betelgeuse won’t be bright enough to appear as a second sun in our sky. Instead, anyone alive on Earth when it happens will be treated to an amazingly beautiful sight in the night sky – a very, very, very bright star. Will the explosion of Betelgeuse destroy earthly life?

When Betelgeuse does blow up, our planet Earth is too far away for this explosion to harm, much less destroy, life on Earth. Astrophysicists say we’d have to be within 50 light-years of a supernova for it to harm us. Betelgeuse is nearly 10 times this distance. So we’re safe from Betelgeuse. And, in fact, if there are any astronomers around when it does blow, they will be extremely thrilled to have a relatively nearby supernova to study. Artist’s concept showing star Betelgeuse (center), with a series of arcs immediately to the left of the star. The arcs are thought to be material ejected from Betelgeuse as it evolved into a red supergiant. Notice the faint linear bar of dust on the left side of the image. It represents a dusty filament connected to our galaxy’s magnetic field, or the edge of an interstellar cloud. If this filament, or wall, exists – as some astronomers believe – the arcs ejected from Betelgeuse will hit the wall 5,000 years from now. Betelgeuse itself will collide with the wall 12,500 years later.

Image via ESA/Herschel/PACS/L. Decin et al. Read more about this image here. What will happen when Betelgeuse goes supernova? Fortunately for us, it appears that there will be few, if any, adverse affects to Earth when Betelgeuse goes supernova. If Betelgeuse were side by side with our sun, you’d find it 10,000 times brighter than the sun in visible light. It might be surprising then to learn that the surface temperature of Betelgeuse is only about 6,000 degrees F (3,600K) in contrast to the sun’s 10,000 degrees F. In terms of mass, Betelgeuse is thought to be about 15 times the mass of the sun, but 600 times wider and more than 200 million times its volume! When you consider its size, as well as the infrared and other radiations it pumps out, Betelgeuse probably outshines our sun by at least 50,000 times. Betelgeuse is one of two very bright stars in the constellation Orion the Hunter.

The other bright star is Rigel. Notice Betelgeuse and Rigel on either side of the short, straight row of three medium-bright stars. That row of stars represents Orion’s Belt. Betelgeuse is said to represent the right shoulder of the Hunter. How to see the star Betelgeuse in the night sky. At mid-northern latitudes, around the first of every year, Betelgeuse rises around sunset. The star is very well placed for viewing on January and February evenings. By the beginning of March, this star is due south in early evening. By mid-May, it can be glimpsed briefly in the west after sunset. Betelgeuse is traveling behind the sun in early summer, but it returns to the east before dawn by about mid-July. Betelgeuse – in the famous constellation Orion – is easy to spot. See our sky chart to learn the pattern of the constellation Orion the Hunter. Orion itself is noticeable for the short, straight row of three medium-bright stars in its mid-section. Betelgeuse is in the upper left corner of the large rectangle forming Orion. The star Betelgeuse has a distinctive color: somber orange-red.

It’s ideal for convincing non-believers that stars do, in fact, come in colors. Stars designated as Alpha are typically brightest in their constellations. But Betelgeuse is Alpha Orionis, despite the fact that it’s fainter than Orion’s other bright star, Rigel . Betelgeuse is the 10th brightest star in the sky overall, and it’s the 7th brightest star visible from most of the U.S., Canada, Europe and the majority of the northern hemisphere. Betelgeuse is often said to represent the right shoulder of the Orion the Hunter. Diagram via stardate.org. Betelgeuse in pop culture, history and mythology. Remember the movie Beetlejuice ? This star’s name is similar. The proper names of many bright stars are Arabic in origin. This fact reflects the dominance of Arabic astronomers and astrologers during Europe’s Dark Ages. The name Betelgeuse apparently is derived from an Arabic phrase that is usually translated as The Armpit of the Giant. Of course the Giant refers to Orion, but – rather than an armpit – some authors see Betelgeuse as representing a hand or sometimes a shoulder.

While it is not entirely clear what the name means, in any event, Betelgeuse marks the right shoulder of Orion in many old star maps. In the ancient myths, Orion is most often associated with a giant, a warrior, a hunter, a god or some other anthropomorphic or animal figure, so it is not surprising that most depictions of Betelgeuse have an anatomical connection. The Sanskrit name signified an arm, too, for example, although it likely was really the leg of a stag. In parts of Brazil Betelgeuse was seen as the hind leg of a cayman (crocodilian) or the foreleg of a turtle. On the other hand, in ancient Japan, Betelgeuse was considered to be part of the rim of a ceremonial drum. In Peru, it was one of four vultures about the devour a criminal. Jim Livingston wrote in October, 2016: “I love the golden colors of Betelgeuse against the velvety black night sky.” Bottom line: The star Betelgeuse is destined to explode someday as a supernova. But don’t worry. The chances of it exploding in our lifetimes are … well, astronomically small.

Even if it did explode, it would not destroy or even harm earthly life. It would not add a second sun to Earth’s sky. It would most likely simply be a wonderful natural event. If, when it happens, people are still watching the skies, then they’ll have something awesome to tell their grandchildren. The position of Betelgeuse is RA 05h 55m 10.3053s, dec +07° 24′ 25.4″. Betelgeuse Betelgeuse Betelgeuse is the brightest star in Orion and marks the western shoulder of the constellation. Betelgeuse is one of the largest known stars and is probably at least the size of the orbits of Mars or Jupiter around the sun. That's a diameter about 700 times the size of the Sun or 600 million miles. For a star it has a rather low surface temperature (6000 F compared to the Sun's 10,000 F). The low temperature means that the star will appear orange-red in color. Betelgeuse emits almost 7,500 times as much energy as the Sun.

The combination of size and temperature tells astronomers that the star is a kind of star called a red super giant. Red super giants are stars that are close to the end of their life. Probably within the next ten to hundred thousand years Betelgeuse might end its life in a supernova explosion. The name Betelgeuse comes from the Arabic and is basically a corruption of the phrase "Armpit of the Giant". The star's distance implies that it is not at the same distance as many of the other stars in Orion. Fact Table Rigel: Orion's Brightest Star Rigel: Orion's Brightest Star By Elizabeth Howell, Space.com Contributor | September 19, 2013 06:16pm ET MORE Light from the star Rigel reflects off the dust composing the Witch Head Nebula. Credit: Rogelio Bernal Andreo / NASA Rigel is a blue supergiant that is the brightest star in the constellation Orion (the Hunter). The star is only 10 million years old, compared to the sun's 4.5 billion, and due to its measured size and brightness it is expected to end in a supernova one day.

It also has two known companions, Rigel B and Rigel C. The star is variable and is considered an Alpha Cygni-type star. (Alpha Cygni is the scientific name for Deneb, the prototype star for this kind of variability.) Its luminosity is so bright that it shines and scatters in an adjacent nebula, called the Witch Head Nebula,which is about 40 Earth-sun distances or astronomical units away. In science fiction, Rigel's name is on a a number of planets in the Star Trek universe, is mentioned in The Hitchhiker's Guide to the Galaxy, and also features in a number of novels, computer games and comic books. Rigel before modern astronomy Rigel's name comes from an Arabic phrase, Rijl Jauzah al Yusrāʽ. It means "the left leg of the Jauzah," according to Richard Hinckley Allen's "Star Names: Their Lore and Meaning." It is also sometimes translated as "the left leg of the giant," reportedly referring to the constellation Orion , of which Rigel forms a part. Rigel is more properly known as Beta Orionis.

Scandinavian folklore said that Rigel indicated one of the large toes of Orwandil; the thunder god Thor broke off the other toe when it was frost-bitten, according to a report recorded by Allen. In Japanese culture, Rigel is sometimes called Genji Boshi and a bright red star in Orion — Betelgeuse — has the name of Heike Boshi. Those names hearken back to the Heian era (794-1192) in Japan, according to an online account by Steve Renshaw and Saori Ihara . (A later version of the account was published in the "Kyoto Journal" in 2000.) "The legendary war that brought the somewhat artistic and gentle Heian era to a close took place between the Taira (Heike) and Minamoto (Genji) families," the authors wrote. "The colors of Taira were red, and the colors of the Minamoto family were white. Ultimately, the Minamoto (Rigel) family won the war and moved the capital to Kamakura, ushering in an era of Samurai warriors and leading to centuries of little true peace ...

These two bright stars of red and white still do battle with the steepes of the belt holding them apart." Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz. 0 of 10 questions complete Star Quiz: Test Your Stellar Smarts Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz. 0 of Start Over | More Quizzes Locating Rigel Rigel is today known as a class B supergiant. It's close to zero magnitude in Earth's sky, making it a bright star . But Rigel is also intrinsically luminous, shining with the equivalent light of 85,000 suns, according to astronomer Jim Kaler . Its radius is 73 times that of the sun.

Rigel's location is: Right ascension: 5 hours 14 minute 32.3 seconds Declination: -8 degrees 12 minutes 6 seconds Rigel to astronomers Astronomers believe the star is about 10 million years old and that later in its life, it will likely transform into a red supergiant (just like Betelgeuse) and eventually explode into a supernova, Kaler added. "If and when it does go, it would appear to us as bright as a quarter moon," Kaler wrote. Rigel also has two distant stellar companions, Rigel B and Rigel C – a binary system. At the ninth magnitude, the combined light of these stars would usually be enough for most telescopes to pick up, but they are too close to the bright Rigel to be easily visible. Rigel's bright starlight also bounces off a nebula some 40 light-years away, as shown in a picture published in 2012 on NASA's Astronomy Picture of the Day website .

"The blue color of the Witch Head Nebula and of the dust surrounding Rigel is caused not only by Rigel's intense blue starlight, but because the dust grains scatter blue light more efficiently than red," NASA wrote. "The same physical process causes Earth's daytime sky to appear blue, although the scatterers in Earth's atmosphere are molecules of nitrogen and oxygen." Rigel in science fiction The name "Rigel" is a popular planetary name in "Star Trek," with references to it popping up in multiple versions of the series. The earliest mention of it was in the original 1960s-era pilot, "The Cage", which referred to Rigel VII. Although that episode did not actually air until the 1980s, Rigel VII and much of the footage from 'The Cage" was used in the two-part episode, "The Menagerie." A few other uses of Rigel: In Douglas Adams' "The Hitchhiker's Guide to the Galaxy," Rigel (presumably it is Rigel, as the name "Orion Beta" is used) was the site of madranite mining belts.

Several computer games of the 1980s and 1990s, such as "Rescue at Rigel,""Rigel's Revenge" and"Duke Nukem II." A Season 2 episode of "The Simpsons," "Hungry Are the Damned", where the family is temporarily kidnapped by a couple of aliens from Rigel IV. In comic book series such as "Justice League," "Thor," "Transformers" and "Monty." Author Bio Elizabeth Howell, Space.com Contributor Elizabeth Howell is a contributing writer for Space.com who is one of the few Canadian journalists to report regularly on space exploration. She is pursuing a Ph.D. part-time in aerospace sciences (University of North Dakota) after completing an M.Sc. (space studies) at the same institution. She also holds a bachelor of journalism degree from Carleton University. Besides writing, Elizabeth teaches communications at the university and community college level. To see her latest projects, follow Elizabeth on Twitter at @HowellSpace .

Elizabeth Howell, Space.com Contributor on Latest on Rigel: Orion's Brightest Star Betelgeuse Star - Facts About Betelgeuse | Solarsystemquick.com Betelgeuse Star Infrared image of Betelgeuse, the two white areas are hotspots on the star's surface. Betelgeuse Facts Betelgeuse is 640 light years from Earth. It is classed as a red supergiant and is the tenth brightest star in the night sky. As part of the Orion constellation Betelgeuse can be easily found in the night sky through most of the year. High mass stars such as Betelgeuse burn their fuel extremely quickly, as a result they exist for only a few million years, stars such as our sun exist for billions of years. At only 10 million years old Betelgeuse is already near the end of its lifespan and is expected to explode as a supernova in the next million years. Supernovas occur when high mass stars can no longer fuse elements in their core. When Betelgeuse explodes it will appear as bright as the moon in the night sky for several weeks and may even be visible during the day.

Supernovas produce deadly bursts of gamma ray radiation but fortunately Betelgeuse is too far away to cause any damage to Earth. Betelgeuse can acceptably be pronounced as 'Beetlejuice' although there are several variations in its pronouncement. Betelgeuse which can be seen top left of center is part of the Orion constellation. Betelgeuse Radius Betelgeuse has around a thousand times the radius of the sun, if it was placed in the center of our solar system the star would reach beyond the orbit of Jupiter! Betelgeuse Mass Betelgeuse is estimated to have a maximum mass of around 20 to 30 times that of the sun. Betelgeuse Temperature Betelgeuse is estimated to have surface temperatures of around 3200C (5800F), around 60% as hot as the sun. Betelgeuse Luminosity (energy emitted) Due to its enormous size Betelgeuse is around 100,000 times more luminous than the sun.

Betelgeuse Statistics Also Known As: Alpha Orionis Distance From Earth: 640 light years Constellation: Orion Star Type: Class M Supergiant Mass: Estimates average around 20 times the mass of the sun Luminosity: Approx 100,000 x Sun Diameter: Approx 850 million miles (1.4 billion km) - 1000 x Sun Temperature: Approx 3200C (5800F) Age: Approx 10 million years old Rotation Period: Estimated around 15 to 30 years Share this page Betelgeuse - Universe Today Universe Today by Jean Tate [/caption] Betelgeuse is the ninth brightest star in the sky, and the second brightest in the constellation of Orion (it’s the red one, on the opposite side of the Belt from Rigel, which is the blue one, and the brightest). With a mass of some 20 sols (= the mass of 20 Suns), Betelgeuse is evolving rapidly, even though it’s only a few million years old.

It’s now a red supergiant, burning helium in a shell, and (very likely) burning carbon in another shell (closer to the nucleus), and (possibly) oxygen, silicon, and sulfur in other nested shells (like Russian dolls). Betelgeuse is enormous … if it were where the Sun is, all four inner planets would be inside it! Because it’s so big, and is only approx 640 light-years away, Betelgeuse appears to about 1/20 of an arcsecond in size; this made it an ideal target for optical interferometry. And so it was that in 1920 Michelson and Pease used the 100″ Mt Wilson telescope, with a 20 m interferometer attached to the front, to measure Betelgeuse’s diameter. The Hubble Space Telescope imaged Betelgeuse directly , in 1995, in the ultraviolet (see above). Why the UV? Because ground-based telescopes can’t make such observations, and because the Hubble’s resolution is greatest in the UV.

Since the 1920s Betelgeuse has been observed, from the ground, by many different optical interferometers, at many wavelengths. Its diameter varies somewhat, as does its brightness (Herschel is perhaps the first astronomer to describe its variability, in 1836). It also has ‘hotspots’, which are ginormous. Betelgeuse is also shedding mass in giant plumes that stretch to over six times its diameter. Although these plumes will certainly cause it to ‘slim down’, they won’t be enough to stop its core turning to iron (when the silicon there is exhausted, if it hasn’t already done so). Not long afterwards, perhaps within the next thousand years or so, Betelgeuse will go supernova … making it the brightest and most spectacular supernova visible from Earth in perhaps a million years.

Fortunately, because we are not looking directly down on its pole, when Betelgeuse does go bang, we won’t be fried by a gamma ray burst (GRB) which may occur (while a core collapse supernova can cause one kind of GRB, it is not yet known if all such supernovae produce GRBs; in any case, such a GRB is one of a pair of jets which rip through the poles of the dying star). AAVSO has an excellent article on Betelgeuse, and COAST’s (Cambridge Optical Aperture Synthesis Telescope) webpage on its observations of Betelgeuse gives a good summary of one interferometric technique (and some great images too!). Universe Today has many stories on just about every aspect of Betelgeuse, from its varying size ( The Curious Case of the Shrinking Star ), the bubbles it’s blowing and its plumes ( Closest Ever Look at Betelgeuse Reveals its Fiery Secret ), featured in What’s Up This Week , to the bow shock it creates in the interstellar medium ( The Bow Shock of Betelgeuse Revealed ).

Astronomy Cast’s The Life of Other Stars is a whole episode on the evolution of stars other than the Sun. References: Betelgeuse - definition of Betelgeuse by The Free Dictionary Betelgeuse - definition of Betelgeuse by The Free Dictionary Also found in: Thesaurus , Encyclopedia , Wikipedia . Related to Betelgeuse: Rigel n. A bright-red intrinsic variable star, 527 light years from Earth, in the constellation Orion. [French Bételgeuse, ultimately from Arabic yad al-jawzā' : yad, hand; see yd in the Appendix of Semitic roots + al-, the + jawzā', Gemini (later also used for Orion) (perhaps from jawz, middle (Gemini perhaps originally being so called because it crossed the middle of the sky, and Orion later being so called because of the three bright stars in the middle of the constellation, forming Orion's belt) , from jāza, to pass through; see gwz in the Appendix of Semitic roots).] Word History: The history of the curious star name Betelgeuse is a good example of how scholarly errors can creep into language.

The story starts with the pre-Islamic Arabic astronomers, who called the star yad al-jawzā', "hand of the jawzā'." The jawzā' was their name for the constellation Gemini. After Greek astronomy became known to the Arabs, the word came to be applied to the constellation Orion as well. Some centuries later, when scribes writing in Medieval Latin tried to render the word, they misread the y as a b (the two corresponding Arabic letters are very similar when used as the first letter in a word), leading to the Medieval Latin form Bedalgeuze. In the Renaissance, another set of scholars trying to figure out the name interpreted the first syllable bed- as being derived from a putative Arabic word *bāṭ meaning "armpit." This word did not exist; it would correctly have been ibṭ. Nonetheless, the error stuck, and the resultant etymologically "improved" spelling Betelgeuse was borrowed into French as Bételgeuse, whence English Betelgeuse. Betelgeuse Betelgeux n (Celestial Objects) a very remote luminous red supergiant, Alpha Orionis: the second brightest star in the constellation Orion.

It is a variable star [C18: from French, from Arabic bīt al-jauzā' literally: shoulder of the giant, that is, of Orion] Be•tel•geuse Betelgeuse: The Eventual Supernova Betelgeuse: The Eventual Supernova By Elizabeth Howell, Space.com Contributor | July 18, 2013 04:14am ET MORE This cool space wallpaper is a composite color image of the Herschel PACS 70, 100, 160 micron-wavelength images of Betelgeuse. Credit: ESA/Herschel/PACS/L. Decin et al Betelgeuse is a star nearing the end of its life. Because it is creating heavier and heavier elements in its core that could be used for stars after it dies, a NASA story once dubbed the red giant a workaholic . The star is a famous one among amateur astronomers not only for its size and brightness, but also because it is part of Orion , a bright winter constellation in the Northern Hemisphere.

Professional astronomers also keep a close eye on the star, as it is notoriously variable: its diameter changes from anywhere between 550 to 920 times the sun's diameter . In 2013, astronomers said Betelgeuse is likely to crash into a "cosmic wall" of interstellar dust in a few thousand years. Locating Betelgeuse Ancient astronomers would have easily spotted Betelgeuse because of its size and relatively close distance from Earth: it is about 600 light-years away and has a variable brightness generally peaking at 0.4 and falling below 1.2. Some 20th-century observations by the American Association of Variable Star Observers suggested peak magnitudes of 0.2 in 1933 and 1942 . It is the 12th brightest star in the night sky.

[ The Brightest Stars in the Sky: A Starry Countdown ] The star's location is: Right ascension: 05 hours 55 minutes 10.3 seconds Declination: +07 degrees 24 minutes 25 seconds It is probable that the name "Betelgeuse" originated in Arabic words, but the star had other names (for example) in Sanskrit, traditional Chinese and even in Hawaiian; in the latter, it was known as Kauluakoko. The coming supernova When astronomers say Betelgeuse is expected to explode soon, they mean shortly in astronomical terms: within a million years, according to several sources. Predicting exactly when it will turn into a supernova is difficult, however, as it depends on precise calculations of its mass as well as an understanding of what is going on inside the star. Betelgeuse is so vast — its size would extend beyond Jupiter's orbit if it were placed in the sun's position in the solar system — that several telescopes have captured images of the star and spotted it shedding mass.

Starting in 1993 and continuing for at least 15 years, its radius shrank by 15 percent , an astonishing amount for so short a time. "We do not know why the star is shrinking," said Edward Wishnow, a research physicist at UC Berkeley's Space Sciences Laboratory, in 2009. "Considering all that we know about galaxies and the distant universe, there are still lots of things we don't know about stars, including what happens as red giants near the ends of their lives." Nearing the wall As the star prepares for what could be a large explosion, another challenge awaits: it is expected to crash into a wall of interstellar dust in the next few thousand years . An infrared Herschel Space Observatory image released in 2013 suggested it would crash into the dust at a speed of 66,960 miles per hour (107,761 kilometers per hour.) The crash would take a while to complete: the solar wind is expected to touch the line around 5,000 years from now, with the heart of the star crashing into the bar 12,500 years after that.

Though they look serene and silent from our vantage on Earth, stars are actually roiling balls of violent plasma. Test your stellar smarts with this quiz. Procyon is the Little Dog Star | Brightest Stars | EarthSky Want to know more about astronomy? Sign up for our free daily newsletter today! View larger. | Orion with his Dogs. The Dog Stars are Sirius in the constellation Canis Major, and Procyon in the constellation Canis Minor. In this photo, Orion is in the upper right. Notice that the three stars of Orion’s Belt point to the brightest star in this photo, Sirius. Procyon is the bright star on the far left of the photo. Procyon and Sirius make a large triangle with the bright star Betelgeuse in Orion. Taken in February 2013 by EarthSky Facebook friend Daniel McVey over White River National Forest – Summit County, Colorado. Thank you, Daniel! See more photos from Daniel McVey on his Facebook page. Procyon is easy to find on winter and spring evenings, in a large pattern made of three bright stars, known as the Winter Triangle. How to see Procyon.

Look for Procyon in the evening in the winter and spring months. By March of every year, Procyon is at or near the meridian (highest point in the sky) at early evening. By June, Procyon sets not long after dark. Procyon is the brightest star in Canis Minor the Lesser Dog. This constellation is small, with only one other noteworthy star, named Gomeisa. Sometimes, Canis Minor is called the Hot Dog. Sometimes Procyon is called the Lesser Dog Star or Little Dog Star. Our chart shows Procyon as a member of the Winter Triangle asterism. In other words, these stars are not a recognized constellation – just a group of noticeable stars that happen to form a triangle pattern on the sky’s dome. Fainter than blue-white Sirius to its south, white Procyon is marginally brighter than orange-red Betelgeuse to the west. The best time to view Procyon is at evening in late winter through spring, when the Winter Triangle (Sirius, Procyon, Betelgeuse) is highest in the sky.

At magnitude 0.4, Procyon is almost the same brightness as nearby Betelgeuse in Orion, with average magnitude 0.45. (Remember, in the magnitude system, larger numbers are fainter.) “Procyon” is also the genus designation of raccoons. University of Michigan Museum of Zoology Procyon in history and mythology. Procyon is the alpha star of the constellation Canis Minor the Small Dog. In mythology, Canis Minor is the smaller of two of Orion the Hunter’s companion hunting dogs. The constellation Canis Major depicts the Great Dog, highlighted by Sirius , the sky’s brightest star (after the sun). The name Procyon is from Greek and means “before the dog,” a reference to the rising of this star shortly before Sirius, the larger Dog Star in the constellation Canis Major. Procyon’s rising time was particularly important in ancient Egypt, because the helical rising – or rising just before the sun – of Sirius heralded the annual flooding of the Nile River. Thus the rising of Procyon just before Sirius gave even more advanced warning.

Procyon still does rise before Sirius as seen from mid-northern latitudes, like those in the northern United States. But from the southern U.S. and similar latitudes – for example, Cairo in Egypt – Sirius now rises before Procyon! Thus an observer in Cairo today would find that Sirius rising a couple of minutes before Procyon and the reason for the name “before the dog” no longer applies. This change is due to a kind of long-term wobble in Earth’s motion, called precession. An aside: “procyon” is also the genus designation of raccoons. Apparently the “before the dog” appellation indicated that biologists once considered raccoons as the precursors of dogs in the evolutionary sequence – an idea no longer in favor. Read more about Procyon from Daniel Perley at Berkeley. Procyon science. The star Procyon is nearing the end stages of its lifetime, evolving from a normal mature star to the inflated giant stages of old age. Normal stars spend the large majority of their lifetimes converting hydrogen into helium. As the available hydrogen runs out, a star grows larger and its surface becomes cooler.

Eventually Procyon will become a red giant star, much larger and brighter than the sun, but that is still some millions of years in the future. Currently Procyon is designated as an F5IV-V star, where the F5 essentially gives the color or temperature of the star’s surface, and the IV-V means that it is in a transitional phase between the Main Sequence (V) and subdwarf (IV) periods. Only 11.4 light-years away, Procyon is one of our nearest stellar neighbors. It is about 1.4 times as massive as the sun, and has roughly twice its diameter. Slightly more than 7 times brighter than the sun, Procyon’s hotter surface (about 11,300 degrees F (6550K) compared to about 10,000 degrees F for the sun) radiates more of the higher energy but shorter wavelengths of light. As such, it is nearly 8 times more energetic (luminous) than the sun. Procyon is a double star with a faint white dwarf companion that is not visible except in telescopes.

The white dwarf, Procyon B, is farther along in its evolution than Procyon, and in fact has reached the end of the line. It no longer produces stable hydrogen fusion and is considered a “dead” star. The reasonable assumption is that these two stars formed at the same time, so the fact that Procyon B has already become a stellar corpse indicates that it originally must have been slightly more massive than Procyon. More massive stars tend to burn their fuel hotter and faster, causing them to burn out sooner. The position of Procyon is RA 07h 39m 18.1/17.7s, dec +05° 13′ 29/20″.

Question: Betelgeuse is the brightest star in which constellation
Answer: Orion