The sky has many bright stars, some of which are close to the sun while others are very far away. However, with the naked eye, all the stars appear almost similar but the reality is that stars come in different sizes, colors, masses, spectra, and composition. A magnitude is a value assigned to the brightness of a star. The lower the value of the magnitude, the brighter the star appears. Although some of the brightest stars on the Earth’s sky are known as multiple stellar systems, they appear as single stars when observed using the naked eyes. Below are the ten brightest stars in the sky.
Rigel is a star located in the constellation of Orion whose brightness varies slightly. This star has a visual magnitude of +0.18 and is a multiple star system consisting of a bright star known as supergiant Rigel A and a slightly dimmer companion star. The companion star consist of three stars, namely Rigel Ba, Bb, and C. Rigel is located some 860 light-years from the solar system. It is classified as Type B8 and is mainly visible between October and March.
Procyon is one of the most important stars in the constellation of Canis Minor. With a visual apparent magnitude of +0.34, it is the 8th brightest star in the night sky. Procyon is a binary star system consisting of Procyon A and a deem companion. It is classified as Type F5 star, meaning that it is slightly cooler than the sun. The star lies approximately 11 light-years from the planet Earth and is twice the size of the sun.
Capella is a bright star in the constellation of Auriga and a common object in the northern winter night sky. Its name is a Latin word for “little she-goat” for its depiction of a goat that suckled Zeus in classical mythology. Although Capella appears as a single star when observed with naked eyes, it consists of four stars grouped into two binary pairs; Capella L, Capella H, Capella Aa, and Capella Ab. Capella Aa and Ab are both giant stars and over twice as massive as the sun.
Vega, whose name means “the swooping eagle,” is the 5th brightest star in the night sky. It is also the brightest star located in the constellation of Lyra. Vega is only 25 light-years from the sun and is among the most luminous stars neighboring the sun. it is about three times bigger than the sun and classified by astronomers as Type A star, meaning that it is younger but hotter than the sun. Vega has been widely studied and is considered by astronomers as the second most important star in the sky after the sun. As a result of combustion, the star is still transforming its hydrogen content into helium.
Achernar is the brightest star in the southern tip of the constellation of Eridanus. It is a binary star system consisting of two stars; Alpha Eridani A which is the primary star and Alpha Eridani B or Achernar B. The name Achernar is an Arabic word meaning “End of the River,” as it is part of the constellation of Eridanus (river). It is the hottest and bluest of the nine brightest night stars, being of a spectral type B. The mass of Achernar is almost seven times of the sun's mass and it is and 3,150 times more luminous than the sun.
Arcturus is the brightest star in the constellation of Bootes and the 4th brightest in the sky at night. Its name is a Greek word meaning “Guardian of the Bear.” Arcturus is one of the closest stars to the sun at only 36.7 light-years and is an orange giant mainly prominent during springtime. This star is twice as massive as the sun and has an apparent magnitude of -0.05. It is visible from both hemispheres. Arcturus has been classified by astronomers as a type K5 star which means that the star is slightly cooler and also older than the sun.
4. Rigil Kentaurus and Toliman
Rigil Kentaurus and Toliman, commonly known as Alpha Centauri, is the closest star to the solar system at only 4.37 light-years from the sun. It consists of three stars, namely Alpha Centauri A, B, and C. Alpha Centauri C is the closest to the sun and not visible to the naked eye. When observed using naked eyes, Alpha Centauri A and B appear as one star with an apparent magnitude of -0.27. Alpha Centauri is located in the constellation of Centaurus and is classified as G2V star. It is about the same age and evolutionary period as the sun.
Canopus is the second brightest star in the night skies with a visual magnitude of 0.74 and is mainly visible from the Southern Hemisphere. It is also known by several names including Alpha Carinae, Suheil, HR 2326, and Suhel. Canopus is an important navigational beacon, especially for spacecrafts on interplanetary trips. This star is approximately 74 light-years away from the Earth and is located on Constellation Carinas. Its mass is approximately eight times that of the sun. It is also slightly hotter and more aged than the sun.
Sirius is known by several names including Dog Star and Alpha Canis Majoris among other names. It is the brightest star in the sky at night. The star is named after the Greek word “scorching” and was considered a sacred star in some cultures. Sirius is visible from almost the entire planet Earth and has a visual magnitude -1.46. It is a multiple star system consisting of the main-sequence star (Sirius A) and a deem white dwarf (Sirius B). The mass of Sirius A is twice that of the sun. This star appears brightest because of its proximity to the solar system and its intrinsic luminosity.
The sun is considered the brightest star in the sky with an apparent magnitude of -26.74. It is the main source of energy and light for life on Earth. The sun is located at the center of the solar system and has a diameter of about 864,000 miles and accounts for over 99% of the mass of the solar system. This star is mainly made up of hydrogen (73%) and helium (25%). The sun is characterized by a white color when it is high in the sky and yellow, orange, or red when it is low in the sky. It is a G2V star indicating that it is a main-sequence star with a surface temperature of about 5,500 degrees Celsius.