[34], RegulusA is a binary star consisting of a blue-white subgiant star of spectral type B8, which is orbited by a star of at least 0.3solar masses, which is probably a white dwarf. NGC 3607 is a spiral galaxy in Leo. Regulus, the brightest star in the constellation Leo, the lion, is a harbinger of spring in the Northern Hemisphere. The primary component in the system, the blue supergiant, has a companion located at an angular separation of 0.11 arc seconds. The other components of the Alpha Leonis system are still on the main sequence, but considerably fainter than Regulus A. Start your review of Academic Urology & Urogynecology. [4] When the stars were aligned accordingly, favourable conditions followed, and when they were negatively aligned, disaster was predicted. Regulus is easy to find and identify because it is part of a prominent asterism known as the Sickle of Leo. The star is an exceptionally fast rotator, with a rotation period of only 15.9 hours. Look towards Regulus around that date and youll see the sun. Regulus is not a binary star for once, although there is a binary nearby, and possibly a white dwarf. If you use any of the content on this page in your own work, please use the code below to cite this page as the source of the content. Your email address will only be used for EarthSky content. Regulus is the faintest of the 22 first-magnitude stars. In 1978, Don was one of the independent inventors of the Messier Marathon, an attempt to find and view all 110 galaxies, clusters, and nebulae in one night. He began his 1st comet hunting program in 1975 and found his 1st comet in 1978, after 1700 hours of searching. Albert George Wilson found it on photographic plates taken as part of the National Geographic Society-Palomar Observatory Sky Survey in 1950. NGC 3357 is an elliptical galaxy in Leo. The planet Venus passes the star around this time every eight years. I am the child of earth and starry heaven. Petelia Tablet, We are all in the gutter, but some of us are looking at the stars. Oscar Wilde. [3], By 700 BCE the Assyrians had essentially mapped the ecliptic cycle because of the four stars and were in result able to map the constellations, distinguishing them from the planets and the fixed stars.[4]. Its extended envelope is believed to have at least 1.4 solar masses of ejected material. It is 85 times more luminous than the Sun. It would be another 40 years before anyone viewed it visually. In Arabic, it is . The two stars complete an orbit around their common centre of mass every 40 days or so. Merak and Dubhe, the outer stars of the Big Dippers bowl, also point in the general direction of the constellation Leo. Experience the game! It has an apparent magnitude of 1.35 and lies at a distance of 79.3 light years, or 24.3 parsecs, from Earth. (CC BY 4.0). Icarus was discovered in 2018 by a team of astronomers who were studying the multiply lensed supernova SN Refsdal with the Hubble Space Telescope. Omicron Leonis is a double star in Leo. As a result, the star is emitting polarized light. It belongs to the spectral class M2.5 V. An extrasolar planet, Gliese 436b, was discovered in the stars orbit in 2004, and the presence of another planet, UCF-1.01, was confirmed in 2012. . "The picture makes me wonder what it would be like to be in a solar system with this type of star.". The two stars have an orbital period of 500 years. The first is a K2V star, while the second is about M4V. Its traditional name, Algieba or Al Gieba, comes from the Arabic Al-Jabhah, which means the forehead. The star is sometimes also known by its Latin name, Juba. The constellation Leo was mentioned in the Tetrabiblos, an ancient Roman text by Ptolemy (c. A.D. 100 170). It was discovered by William Herschel in 1784. In other words, they are the brightest stars in the sky. A line from Megrez through Phecda, the inner stars of the Big Dippers bowl, leads to the Sickle. The existence of a white dwarf companion would mean that the system is at least 1 billion years old, just to account for the formation of the white dwarf. Christians in the Middle Ages sometimes referred to it as one of Daniels lions. As for what causes the rapid rotation, astronomers at the time said it was a mystery. According to the first one, the constellation represents seven brothers and their sister who fled to the sky to escape a pursuer. Regulus Star Facts & Features About The Little King. The constellation was first catalogued by the Greek astronomer Ptolemy in the 2nd century, along with all the other constellations of the zodiac. In the MUL.APIN, a catalogue of stars and constellations in Babylon, Regulus was listed as LUGAL. Messier 66, image: Adam Block/Mount Lemmon SkyCenter/University of Arizona (CC BY-SA 4.0). Differential bending of light was measured to be consistent with general relativity. He received his 1st telescope in 1965, a 2-inch (5cm) refractor. The two asterisms overlap in the spring night sky. The next brightest star to the ecliptic is Wasat, Delta Geminorum, with a visual magnitude of 3.53. The equatorial diameter of Regulus is 32 percent larger than its polar diameter. The galaxy has an apparent magnitude of 12.8 and is approximately 331 million light years distant from Earth. My latest is an analysis of the Njord Skadi myth, from Avalonia Books. Image: ESA/Hubble & NASA and the LEGUS Team, acknowledgement: R. Gendler. This blog allows me to explore ideas and get reactions and suggestions from readers. Regulus is the only 1st magnitude star to sit almost squarely on the ecliptic, which marks the path of the sun, moon and planets across our sky. Along with Messier 65 and Messier 66, NGC 3628 forms the Leo Triplet galaxy group. Due to the stars oblate shape, its poles are closer to the centre of mass and have a higher effective temperature and therefore brightness, while the equatorial region is cooler and less bright. It's the brightest star in the constellation and among the brightest in Earth's night sky. During the December 2026 occultation, Mars and Jupiter will be nearby. 1415 E University Dr, Suite A105 Tempe, Arizona 85281 Details Maps. So bright planets sometimes pass near Regulus. [citation needed] In Chinese it is known as , the Fourteenth Star of Xuanyuan, the Yellow Emperor. This is because the star is so distorted that it lessens gravity's strength, which then turns down the temperature at the equator, the researchers said. The brighter pair, designated Regulus A, is a spectroscopic binary system consisting of a bright blue star of spectral classification B7 V, and a companion that has not been directly observed, but is likely a white dwarf with a low mass of only 0.3 solar. Regulus is part of a relatively bright asterism known as the Sickle of Leo, which outlines the celestial lions head, mane, and shoulders. By the time of the Persian Empire (550 BC330 BC), Aldebaran watched the Eastern sky and was the dominant star in the Taurus constellation, Regulus watched the North and was the dominant star in the Leo constellation, Antares watched the West and was the alpha star in Scorpio, and Fomalhaut watched the Southern sky and was the brightest star in Piscis Austrinus (sharing the same longitude with the star Sadalmelik which is the predominant star in Aquarius). Eta Leonis is white supergiant belonging to the spectral class A0 Ib. Zeta Leonis has a visual magnitude of 3.33 and is about 274 light years distant from the solar system. The Sickle can be found using the bright stars of the Big Dipper, the most recognizable part of the constellation Ursa Major. It crept higher in the sky with each passing day in March and April, as winter favorites like Orion descended westward. [32], For Earth observers, the heliacal rising (pre-sunrise appearance) of Regulus occurs late in the first week of September, or in the second week. Larry Sessions has written many favorite posts in EarthSky's Tonight area. It can show you might rank high in urban affairs, land management, etc. NGC 2903 is a barred spiral galaxy. Stewart, Suzy. For example, in 1959, Regulus was occulted by Venus. The components in the system are too close together to be able to resolve through a telescope. Major disasters, breakthroughs, and historical phenomenons were seen as caused by the stars and their alignment in the sky during the time in which the event occurred. The galaxy resembles a giant maelstrom of glowing gas, rippled with dark dust that swirls inwards towards the nucleus. It set upon the local inhabitants and could not be defeated because it had impenetrable skin. When you purchase through links on our site, we may earn an affiliate commission. Regulus A is a spectroscopic binary star composed of a blue-white main sequence star belonging to the spectral class B7 V, and a companion star which cannot be resolved, but is believed to be a white dwarf. Astrophotography with a film camera: Is it possible? The constellation name Leo is pronounced /lio/. Lambda Leonis is a K5-class star, about 336 light years from the Sun. Regulus B, meanwhile, has its own companion: Regulus C. At magnitude 13.5, its only visible with powerful telescopes. The flares from the star emit strong bursts of gamma rays and X-ray radiation. . The name Regulus means the "little king" or "prince" in Latin. The Spring Triangle and the Diamond of Virgo, image: Stellarium. National Geographic Society-Palomar Observatory Sky Survey. With an effective temperature of 4,885 K, it is half as luminous as the Sun. Leo's brightest star, Regulus, was often called the "Red Flame" and was thought to contribute to the heat of summer. In contrast, our sun spins on its axis about once every 27 days. It was first discovered by astronomer Pierre Mchain in 1781, and added to Charles Messiers famous catalogue of astronomical objects just four days later. Regulus was associated with Jupiter and Mars, and linked with granite and mugwort. He's a longtime member of NASA's Solar System Ambassadors program. Variations in the spin of the star mean there is probably a white dwarf, or dead star, lurking in the vicinity of Regulus, the astronomers argued in 2008. Heres how it works. In Latin, the name "Regulus" means "little king." (In Arabic, Qalb al-Asad, anglicized to Kabelaced.) Its brightness is 288 times that of the Sun. Leo is one of the oldest constellations in the sky. Amateur astronomers can view it, but this requires dark skies and a large telescope. It has 214% of the solar radius and is about 15 times more luminous than the Sun. The star has an optical companion, 35 Leonis, which has an apparent magnitude of 5.90. If the star were spinning 10 percent faster, it would fly apart as its gravity would not be strong enough to hold it together. Leo is one of the largest northern constellations. DSS is one of the programs of STScI (Space Telescope Science Institute). The star belongs to the IC 2391 supercluster, a stellar association whose member stars share a common motion through space, but are not gravitationally bound. Copernicus called it the Little King, after the Greek Basiliokos. Regulus B is a K2V star and the companion is believed to be a red dwarf of the spectral type M4V. Zosma, Delta Leonis, is another rapid rotator in Leo, with a projected rotational velocity of 180 km/s. It appears as a backward question mark in the night sky. They are located at an angular distance of 177 arc seconds from Regulus A. Later he received a 6-inch (15 cm) Criterion Dynascope and found all the Messier Objects in one year (1969-70). The traditional name Regulus is Latin for ' prince ' or ' little king .'. 35 Leonis is located 325.9 arc seconds away from Adhafera and it is only a line-of-sight companion, as it is only 100 light years distant from Earth. In other words, Kepler's third law, which holds exactly only for two point-like masses, would no longer be valid for the Regulus system. Rgulus is Latin for 'prince' or 'little king';[36] its Greek equivalent (Latinised) is Basiliscus. Regulus spins on its axis once every 16 hours. In Greek mythology, The Greeks associated Constellation Leo with the Nemean Lion. The only time of year when the star cant be seen is for a month on either side of August 22, when it lies too close to the Sun. The two stars are separated by about 100 astronomical units and have an orbital period of 2,000 years. Look through a small telescope using at least 50x magnification, and you can see Regulus as two objects separated by 177 arcseconds. Regulus D is a 12th magnitude star located at a separation of 212 arcseconds. It has a nominal luminosity of 11,300 times that of the Sun, but this varies over the course of the pulsation cycle, from 6,250 to 15,800 times the Suns luminosity. (Regulus axis is tilted 86 degrees.). The stars Greek name, Basiliscos, had the same meaning. Regulus is actually a quadruple-star system composed of four stars that are organized into two pairs. In ancient Greece, the star was known as Basiliskos (little king), while in Rome it was known as Basilica Stella. It is emitting polarized light because of this. 1. The Regulus BC pair can be observed in smaller instruments. Theta Leonis has an estimated age of 550 million years, which means that it is much younger than the Sun. The primary star of Regulus A is a young star, only a few million years old, and has 3.5 times the mass of the Sun. [4] The star has a relatively high projected rotational velocity, 23 km/s. This refers to the star that stands in the breast of the Lion: the King. It is one of the zodiac constellations and one of the largest constellations in the sky. The stars projected rotational velocity is 128 km/s. Regulus is located about 79 light-years from Earth. These stars were considered to be the guardians of the sky in ancient Persia, around the year 3000 BCE. (The Persians called it first Venant and then Miyan (the center). Inferno Escape Room. Every month or so one of the constellations in the belt hides directly behind the Sun opposite to Earth. Only Alpha Centauri in the constellation Centaurus and Barnards Star in Ophiuchus are closer. Retrieved from https://theplanets.org/stars/regulus-star/. Leo constellation is home to the bright stars Regulus and Denebola, the nearby star Wolf 359, and to a number of famous deep sky objects, among them galaxies Messier 65, Messier 66, Messier 95, Messier 96, Messier 105, and NGC 3628. So bright planets sometimes pass near Regulus.. Source. For other uses, see, Notable stars and star systems coplanar with the ecliptic (and sun and approximately its planets, but specifically earth), "Validation of the new Hipparcos reduction", "MSC a catalogue of physical multiple stars", "Spectroscopic Detection of the Pre-White Dwarf Companion of Regulus", "Gaia Early Data Release 3: Summary of the contents and survey properties", "Bulletin of the IAU Working Group on Star Names, No. Regulus B and Regulus C take about 600 years to complete an orbit around a common centre of mass. Map. NGC 3626 is a medium-tightness spiral galaxy in Leo. It has 11 stars with known planets. There is probably another companion as well, according to one research team that did measurements of the spin of Regulus. Gliese 436 is another red dwarf located relatively close to the Sun. A daily update by email. Leo constellation map by IAU and Sky&Telescope magazine. The stars traditional name, Alterf, comes from the Arabic a-arf, which means the view (of the lion).. It was another of the constellations identified by Ptolemy, but records show that it was known to an earlier Greek astronomer named Eudoxus. 2 stars. [40] It was one of the fifteen Behenian stars known to medieval astrologers, associated with granite, mugwort, and the kabbalistic symbol . 163 Erigone, a large, dark asteroid from the asteroid belt, about 73 km in size, occulted Regulus on March 20, 2014. Regulus appears below the Lions head and shoulders and marks its heart. "A companion may be a low mass white dwarf or main sequence star," a preprint version of the research paper read. The main star Regulus A is large and blue with a spectral type of B8 IVn. It is a bluish star, and it can be seen all around the globe. Its surface temperature averages about 12,460 Kelvin (21,970 degrees F or 12,190 degrees C), which is much higher than our suns surface temperature. The galaxy is classified as a double-barred spiral with a small inner bulge through the centre along with an outer bulge. The star Spica - aka Alpha Virginis - is the brightest star in the constellation Virgo the Maiden. Also, with a rotation period of 15.9 hours, Regulus is a lot faster than the Sun. He used the lions claws to cut off its pelt, and then wore the pelt as a cloak, complete with the lions head. His 2nd comet took an additional 1742 hours. If you like the image at the top, click here. The galaxy is known to have a supermassive black hole at its centre. Beta Leonis is a relatively young star. The Persians knew the star as Miyan, the Centre and as Venant, the guardian of the north. Regulus B and Regulus C share a common proper motion. M65 does not contain much dust and gas and there isnt much star formation occurring in it. Regulus lies only 0.46 degrees from the ecliptic, which is the Suns apparent path across the sky, through the zodiac constellations, and is regularly occulted by the Moon and very rarely by Mercury and Venus. It has the Bayer designation designated Leonis, which is Latinized to Alpha Leonis, and abbreviated Alpha Leo or Leo. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. The neighboring constellations are Cancer, Coma Berenices, Crater, Hydra, Leo Minor, Lynx, Sextans, Ursa Major and Virgo. The Arabic phrase is sometimes approximated as Kabelaced. It has a relatively high proper motion. Visitor Centers. The two stars complete an orbit around their common centre of mass every 40 days or so. Despite its proximity to the Sun, Wolf 359 can only be seen through a large telescope. Icarus is the second most distant individual star discovered to date, second only to Earendel (WHL0137-LS) in the constellation Cetus.