Instruct: Given a question, retrieve passages that can help answer the question.
Query: What is the brightest star in the night sky?
Apparent visual magnitudes of the brightest star can also be compared to non-stellar objects in our Solar System. Here the maximum visible magnitudes above the brightest star, Sirius (−1.46), are as follows. Excluding the Sun, the brightest objects are the Moon (−12.7), Venus (−4.89), Jupiter (−2.94), Mars (−2.91), Mercury (−2.45), and Saturn (−0.49).
The star-like objects that Halt reported hovering low to the north and south are thought by some sceptics to have been misinterpretations of bright stars distorted by atmospheric and optical effects, another common source of UFO reports. The brightest of them, to the south, matched the position of Sirius, the brightest star in the night sky.
The Sun has an apparent magnitude of −26.7, but its absolute magnitude is only +4.83. Sirius, the brightest star in the night sky as seen from Earth, is approximately 23 times more luminous than the Sun, while Canopus, the second brightest star in the night sky with an absolute magnitude of −5.53, is approximately 14,000 times more luminous than the Sun. Despite Canopus being vastly more luminous than Sirius, however, Sirius appears brighter than Canopus. This is because Sirius is merely 8.6 light-years from the Earth, while Canopus is much farther away at a distance of 310 light-years.
Nu Eridani (ν Eri) is a star in the constellation Eridanus. It is visible to the naked eye with an apparent visual magnitude of 3.93. The distance to this star is roughly 520 light years, based upon an annual parallax shift of 0.00625 arcseconds. If the star were from the Sun, it would be the brightest star in the night sky with an apparent magnitude of −2.84. (Currently, the brightest star is Sirius at magnitude −1.46.)
In keeping with the pattern of the naming the Algol-class ships after bright stars, the "Regulus" was named after Regulus, the brightest star in the constellation Leo and one of the brightest stars in the night sky.
Although Sirius is the brightest proper star in the night sky, it is away from Earth and has no effect whatsoever on the planet's weather or temperature. Although the star continues to return to the night sky in late summer, its position continues to gradually shift relative to the Sun and will rise in the middle of winter in about 10,000 years.
Canopus (), also designated α Carinae (Latinised to Alpha Carinae, abbreviated Alpha Car, α Car), is the brightest star in the southern constellation of Carina, and the second-brightest star in the night sky, after Sirius. Canopus' visual magnitude is −0.74, and it has an absolute magnitude of −5.71.
Alpha Centauri A and B are Sun-like stars (Class G and K), and together they form the binary star Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of −0.27, forming the brightest star in the southern constellation of Centaurus and the third-brightest in the night sky, outshone only by Sirius and Canopus.
First magnitude stars are the brightest stars in the night sky, with apparent magnitudes lower than +1.50.Hipparchus, in the 1st century B.C., introduced the magnitude scale. He allocated first magnitude to the 20 brightest stars and the sixth magnitude to the faintest stars visible to the naked eye.
In keeping with the pattern of the naming the Algol-class ships after bright stars, the "Altair" was named after Altair, the brightest star in the constellation Aquila and the twelfth brightest star in the night sky.
The car was named after Capella, the brightest star in the constellation Auriga, the sixth-brightest in the night sky and the third-brightest in the northern celestial hemisphere, after Arcturus and Vega.
88 modern constellations by area Historical brightest stars: the brightest star in Earth's night sky at each period within the last or next 5 million years List of largest stars List of most luminous stars List of nearest bright stars List of nearest galaxies List of nearest stars and brown dwarfs Lists of constellations Lists of stars Lists of stars by constellation Stars and planetary systems in fiction
Betelgeuse, also designated α Orionis (Latinised to Alpha Orionis, abbreviated Alpha Ori, α Ori), is on average the ninth-brightest star in the night sky and second-brightest in the constellation of Orion. It is distinctly reddish, and is a semiregular variable star whose apparent magnitude varies between 0.0 and 1.3, the widest range of any first-magnitude star. Betelgeuse is one of three stars that make up the Winter Triangle asterism, and it marks the center of the Winter Hexagon. If the human eye could view all wavelengths of radiation, Betelgeuse would be the brightest star in the night sky.
Capella was the brightest star in the night sky from 210,000 years ago to 160,000 years ago, at about −1.8 in apparent magnitude. At −1.1, Aldebaran was brightest before this period; it and Capella were situated rather close to each other in the sky and approximated boreal pole stars at the time.
Epsilon Canis Majoris (Latinised from ε Canis Majoris, abbreviated Epsilon CMa, ε CMa) is a binary star and, despite being designated ε (epsilon), the second-brightest object in the constellation of Canis Major and one of the brightest stars in the night sky with an apparent magnitude of 1.50. About 4.7 million years ago, it was the brightest star in the sky, with an apparent magnitude of −3.99. Based upon parallax measurements obtained during the Hipparcos mission, it is about 430 light-years distant from the Sun.
Capella, also designated α Aurigae (Latinized to Alpha Aurigae, abbreviated Alpha Aur, α Aur), is the brightest object in the constellation of Auriga, the sixth-brightest star in the night sky, and the third-brightest in the northern celestial hemisphere after Arcturus and Vega. A prominent object in the northern winter sky, it is circumpolar to observers north of 44°N. Its name meaning "little goat" in Latin, Capella depicted the goat Amalthea that suckled Zeus in classical mythology. The Capella system is relatively close, at only from the Sun.
In keeping with the pattern of the naming the Algol-class ships after bright stars, the "Capella" was named after Capella, the brightest star in the constellation Auriga, the sixth brightest in the night sky.
Alpha Trianguli Australis, known as Atria, is a second-magnitude orange giant and the brightest star in the constellation, as well as the 42nd-brightest star in the night sky. Completing the triangle are the two white main sequence stars Beta and Gamma Trianguli Australis. Although the constellation lies in the Milky Way and contains many stars, deep-sky objects are not prominent. Notable features include the open cluster NGC 6025 and planetary nebula NGC 5979.
Canis Major contains Sirius, the brightest star in the night sky, known as the "dog star". It is bright because of its proximity to the Solar System. In contrast, the other bright stars of the constellation are stars of great distance and high luminosity. At magnitude 1.5, Epsilon Canis Majoris (Adhara) is the second-brightest star of the constellation and the brightest source of extreme ultraviolet radiation in the night sky. Next in brightness are the yellow-white supergiant Delta (Wezen) at 1.8, the blue-white giant Beta (Mirzam) at 2.0, blue-white supergiants Eta (Aludra) at 2.4 and Omicron at 3.0, and white spectroscopic binary Zeta (Furud), also at 3.0. The red hypergiant VY Canis Majoris is one of the largest stars known, while the neutron star RX J0720.4-3125 has a radius of a mere 5 km.
Gamma Velorum (Latinised from γ Velorum, abbreviated γ Vel) is a quadruple star system in the constellation Vela. At a combined magnitude +1.7, it is one of the brightest stars in the night sky, and contains by far the closest and brightest Wolf-Rayet star. It has the traditional name Suhail al Muhlif and the modern name Regor, but neither is approved by the International Astronomical Union.
Also named for Canopus is Canopus, the brightest star in the southern constellation of Carina (the "keel" of the ship Argo) and the second-brightest star in the night sky after Sirius.
Betelgeuse is the eighth-brightest star in the night sky and second-brightest star in the constellation of Orion, outshining its neighbour Rigel (Beta Orionis) only rarely. Distinctly reddish-tinted, it is a semiregular variable star whose apparent magnitude oscillates between 0.2 and 1.2, the widest range of any first magnitude star. It marks the upper right vertex of the Winter Triangle and center of the Winter Hexagon.
Canis Major is a prominent constellation because of its many bright stars. These include Sirius (Alpha Canis Majoris), the brightest star in the night sky, as well as three other stars above magnitude 2.0. Furthermore, two other stars are thought to have previously outshone all others in the night sky—Adhara (Epsilon Canis Majoris) shone at -3.99 around 4.7 million years ago, and Mirzam (Beta Canis Majoris) peaked at −3.65 around 4.42 million years ago. Another, NR Canis Majoris, will be brightest at magnitude −0.88 in about 2.87 million years' time.
Arcturus, also designated α Boötis (Latinized to Alpha Boötis, abbreviated Alpha Boo, α Boo), is the brightest star in the constellation of Boötes, the fourth-brightest in the night sky, and the brightest in the northern celestial hemisphere. Together with Spica and Denebola (or Regulus, depending on the source), Arcturus is part of the Spring Triangle asterism and, by extension, also of the Great Diamond along with the star Cor Caroli.
The four dominant stars have an apparent magnitude–1.5 or brighter. The reason why they are called "Royal" is that they appear to stand aside from the other stars in the sky. The four stars, Aldebaran, Regulus, Antares, Fomalhaut, are the brightest stars in their constellations and among the 25–brightest stars in the night sky. The Persians considered these stars to be the four guardians of the heavens. They marked the seasonal changes and marked the equinoxes and solstices.