Quiz Bowl Science Astrology (Stars, Star Types, Constellations)

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Arcturus (Major Stars)

(Alpha Boötis) Arcturus is the brightest star in the constellation Boötes (the herdsman). It is a red giant (spectral type K1.5IIIp) that is the fourth brightest star in the sky. Arcturus is 34 light-years from Earth. It has an apparent magnitude of -0.04 and an absolute magnitude of 0.2.

Antares (Major Stars)

(Alpha Scorpii) Antares (meaning "Rival of Mars") is the brightest star in Scorpius, one of the constellations in the zodiac. Antares is a M1.5Iab variable red supergiant star that is about 520 light-years from Earth and is about 230 times as big as the Sun. This incredibly massive, old, low-temperature (3500 K) star is the 15th brightest star in the sky; it has a visual (apparent) magnitude of +0.96 (var.) and an absolute magnitude of -5.2

Betelgeuse (Major Stars)

(pronounced "beetle juice") Betelgeuse (alpha Orionis) is the second-brightest star in the constellation Orion and one of the brightest stars in the sky. It is a supergiant star, reddish in color, and over 600 million miles in diameter (almost 1,000 times bigger than the Sun but cooler than the Sun). Betelgeuse is about 14,000 times brighter than the Sun. If Betelgeuse were at the center of our Solar System, it would extend beyond the orbit of Jupiter. It is 520 light-years from Earth. It is a variable star, varying in magnitude from 0.3 to 1.2 over a period of about 7 years, averaging about 0.70. It is the only star (other than our sun) for which we have surface images.

Binary Star (Star Type)

A binary star is a system of two stars that rotate around a common center of mass (the barycenter). About half of all stars are in a group of at least two stars.

Blue Giant (Star Type)

A blue giant is a huge, very hot, blue star. It is a post-main sequence star that burns helium.

Brown Dwarf (Star Type)

A brown dwarf is a "star" whose mass is too small to have nuclear fusion occur at its core (the temperature and pressure at its core are insufficient for fusion). A brown dwarf is not very luminous. It is usually regarded as having a mass between 1028 kg and 84 x 1028.

Double Star (Star Type)

A double star is two stars that appear close to one another in the sky. Some are true binaries (two stars that revolve around one another); others just appear together from the Earth because they are both in the same line-of-sight.

Neutron Star (Star Type)

A neutron star is a very small, super-dense star which is composed mostly of tightly-packed neutrons. It has a thin atmosphere of hydrogen. It has a diameter of about 5-10 miles (5-16 km) and a density of roughly 10 15 gm/cm3.

Pulsar (Star Type)

A pulsar is a rapidly spinning neutron star that emits energy in pulses.

Red Giant (Star Type)

A red giant is a relatively old star whose diameter is about 100 times bigger than it was originally, and had become cooler (the surface temperature is under 6,500 K). They are frequently orange in color. Betelgeuse is a red giant. It is about 20 times as massive as the Sun about 14,000 times brighter than the Sun, and about 600 light-years from Earth.

Supergiant (Star Type)

A supergiant is the largest known type of star; some are almost as large as our entire solar system. Betelgeuse and Rigel are Supergiants. These stars are rare. When Supergiants die they supernova and become black holes.

White Dwarf (Star Type)

A white dwarf is a small, very dense, hot star that is made mostly of carbon. These faint stars are what remains after a red giant star loses its outer layers. Their nuclear cores are depleted. They are about the size of the Earth (but tremendously heavier)! They will eventually lose their heat and become a cold, dark black dwarf. Our sun will someday turn into a white dwarf and then a black dwarf. The companion of Sirius is a white dwarf.

G (Star Type)

Absorption lines of neutral metallic atoms and ions (e.g. once-ionized calcium).

Aldebaran (Major Stars)

Aldebaran is the brightest star in the constellation Taurus (it is one of the bull's eyes) and is the 13th brightest star in the sky. Aldebaran is seen along the ecliptic. Aldebaran means "the Follower" in Arabic (since it seems to follow the stars in the Pleiades. Aldebaran is an giant, old, orange star that is cooler than the Sun; it is under 4,000 Kelvin (the Sun is 5,800 Kelvin). Aldebaran is about 40 times as big as the Sun.

Alnitak (Major Stars)

Alnitak (Zeta Orionis) is a star at the eastern end of the Orion's belt (in the constellation Orion). Alnitak means belt. Alnitak is spectral Type O9.7Ib. It is also known as Alnitah.

Alpha Centauri (Major Stars)

Alpha Centauri is the star system that is closest to the Earth. The dimmest star in the system, Proxima Centauri (Alpha Centauri C), is the closest star to us (other than our sun). The stars Alpha Centauri A and Alpha Centauri B are close binary stars

Eclipsing Binary (Star Type)

An eclipsing binary is two close stars that appear to be a single star varying in brightness. The variation in brightness is due to the stars periodically obscuring or enhancing one another. This binary star system is tilted (with respect ot us) so that its orbital plane is viewed from its edge.

Bootes (Major Stars)

Boötes (the herdsman) is a large constellation in the northern hemisphere. The brightest star in Boötes is Arcturus, a red giant that is the fourth brightest star in the sky.

F (Star Type)

Ca II absorption. Metallic lines become noticeable.

Canis Major (Major Stars)

Canis major (The Great Dog) is a constellation near Orion. The brightest star in Canis Major (and the brightest star in the sky) is Sirius, also known as the dog star. Canis Major is one of the constellation Orion's hunting dogs (together with Canis Minor).

Capella (Major Stars)

Capella is a multiple star system containing at least 9 stars. This bright system is in the Northern Hemisphere, 45 degrees from Polaris (the northern pole star); it is in the constellation Auriga. The two brightest stars in Capella are a binary star system. They are both yellow (like our Sun) with masses 2.6 times and 2.7 times that of the Sun. One is 9 times as large as the Sun, the other is 12 times as large. Each gives off roughly 78 times the light as the Sun. These two stars are about 43 light years from Earth.

Cepheid Variable Stars (Star Type)

Cepheid variables are stars that regularly pulsate in size and change in brightness. As the star increases in size, its brightness decreases; then, the reverse occurs. Cepheid Variables may not be permanently variable; the fluctuations may just be an unstable phase the star is going through. Polaris and Delta Cephei are examples of Cepheids.

Deneb (Major Stars)

Deneb (which means "tail" in Arabic) is the brightest star in the constellation Cygnus (the swan); Deneb is also referred to as alpha Cygni, and is the tail of the swan. This young, bright, white supergiant star is perhaps 1,500 light years away. Deneb is about 60,000 times more luminous than the sun!

A (Star Type)

Hydrogen (H) lines strongest for A0 stars, decreasing for other A's.

K (Star Type)

Metallic lines, some blue continuum.

Mira (Major Stars)

Mira (Omicron Ceti) is a well-known variable red giant star in the constellation called Cetus. It was discovered in 1596 by David Fabricus, an amateur Dutch astronomer. Mira (meaning "wonderful") was named by Johannes Hevelius in 1662. Its mass is about the same as our Sun but it varies in size and brightness over a period of 332 days (about 11 months). During this period, its magnitude varies from 3.4 to 9.3.

Nemesis (Major Stars)

Nemesis is a hypothetical companion dark star to our Sun. Once every 30 million years, this dark star would pass through the Oort cloud, triggering comets that perhaps cause periodic mass extinctions on Earth.

B (Star Type)

Neutral helium lines (H II) in absorption.

Polaris (Major Stars)

Polaris (alpha UMi) is the current pole star for the Northern Hemisphere; it is 1 degree from the exact Northern celestial pole. In 1780, Sir William Herschel discovered that Polaris was a double star with a faint companion star. Polaris is a blue-green Cepheid variable star (its size brightness changes periodically, with period of 3.969778 days; it varyies between mag 1.92 and 2.07). Polaris has a relatively dim companion star (9th magnitude). Polaris' distance from Earth has been estimated to be from 360 to 820 light years. At its brightest, Polairs is about 6,000 to 10,000 times brighter than our Sun. It is the larger star at the end of the handle of the Little Dipper (Ursa Minor). Polaris is also called the Lodestar or the Cynosure.

Rigel (Major Stars)

Rigel (beta Orionis) is the brightest star in the constellation Orion and one of the brightest stars in the sky. It is a blue (very hot) supergiant, over 60 million miles in diameter (almost 100 times bigger than the sun). It is more than 50,000 times more luminous than the Sun. It has an absolute magnitude of -7.1 and an apparent magnitude of +0.12. It is over 900 light-years from Earth.

Sirius (Major Stars)

Sirius (meaning "scorching" in Greek), also known as the dog star, is the brightest star in the sky (except for the sun). It is in the constellation Canis Major (The Great Dog). Sirius is a main sequence star that is about 70 times more luminous than the sun. It is about 8.6 light-years from Earth. It has an apparent magnitude of -1.46 and an absolute magnitude of +1.4. Sirius has a companion star (called the Pup), which is a white dwarf.

M (Star Type)

Some molecular bands of titanium oxide.

The Sun (Major Stars)

The Sun is a star at the center of our solar system. Our Sun is a medium-sized yellow star that is 93,026,724 miles (149,680,000 km) from Earth. Its diameter is 865,121 miles (1,391,980 km). At its core, nuclear reactions produce enormous amounts of energy, through the process of converting hydrogen atoms into helium atoms (nuclear fusion). Its absolute magnitude is +4.83. The solar mass is 1.99 x 1030 kg.

Proxima Centauri (Major Stars)

The closest star to us is the Sun. Other than that, the closest star is Proxima Centauri, aka Alpha Centauri C (the dimmest star in the Alpha centauri system). Proxima Centauri is about 4.2 light-years from the Sun. It has an absolute magnitude of 15.5 and an apparent magnitude of +11.05 (variable). Spectral type M5.5Vc.

Closest Stars

The closest stars to the Milky Way Galaxy are: 1. Proxima Centauri 4.2 LY 2. Alpha Centauri A and B 4.3 LY 3. Barnard's Star 6.0 LY 4. Wolf 359 7.7 LY 5. Lalande 21185 8.1 LY

North Star (Major Stars)

The north star is a star that is located almost due north and is useful for navigation. Polaris is currently the pole star of the Northern Hemisphere.

Bright Stars

The top five brightest stars not including the sun are, in decreasing order, Sirius, Canopus, Alpha Centauri, Arcturus, and Vega.

Star Types

They are in order by decreasing temperature, O, B, A, F, G, K, and M. They are classified based on their spectra which are the elements that the stars absorb.

O (Star Type)

They have singly ionized helium lines H I either in emission or absorption and have a strong UV continuum.

Upsilon Andromedae (Major Stars)

Upsilon Andromedae is a star in the constellation Andromeda. Astronomers Geoffrey W. Marcy and R. Paul Butler discovered a massive planet orbiting this star (with each orbit taking only 4.6 days.) in 1996. Recently, 2 even more massive planets have been discovered orbiting this star. The three planets orbit within 2.5 Astronomical Units of the star.

Vega (Major Stars)

Vega (Alpha Lyrae) is a very bright star in the constellation Lyra. It is also known as the Harp Star and Fidis. Vega is the 5th brightest star in the sky and is pale blue. It is about 25 light years from Earth. Its spectral type is A0Va. A disk of dust surrounds Vega, from which planets might form. Vega, together with Deneb and Altair form the Summer Triangle.

X-Ray Binary Stars (Star Type)

X-ray binary stars are a special type of binary star in which one of the stars is a collapsed object such as a white dwarf, neutron star, or black hole. As matter is stripped from the normal star, it falls into the collapsed star, producing X-rays.

Zeta Orionis (Major Stars)

Zeta Orionis (Alnitak) is a star at the eastern end of the Orion's belt (in the constellation Orion). Alnitak means belt. Alnitak is spectral Type O9.7Ib. It is also known as Alnitah.

Sagittarius (Constellations of the Zodiac)

the archer

Taurus (Constellations of the Zodiac)

the bull

Cancer (Constellations of the Zodiac)

the crab

Pisces (Constellations of the Zodiac)

the fish

Capricorn (Constellations of the Zodiac)

the goat

Leo (Constellations of the Zodiac)

the lion

Aries (Constellations of the Zodiac)

the ram

Libra (Constellations of the Zodiac)

the scales

Scorpius (Constellations of the Zodiac)

the scorpion

Gemini (Constellations of the Zodiac)

the twins

Virgo (Constellations of the Zodiac)

the virgin

Aquarius (Constellations of the Zodiac)

the water bearer


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