All About The Corona Borealis Constellation

Corona Borealis is located in the northern hemisphere. The name Corona Borealis means “northern crown” in Latin. It is one of the 48 constellations listed by the Greco-Roman astronomer Ptolemy. It is also part of one of the 88 modern constellations.

Corona Borealis constellation covers about 0.433% of the sky which makes up to 179 square degrees. Onlookers can spot the constellation in the northern hemisphere in spring and summer season.

In 1922, the constellation adopted a three-letter abbreviation called “CrB” through the International Astronomical Union.

Location Of Corona Borealis

Corona Borealis constellation is a small constellation, located far away from the plane of the Milky Way. It is however easy to spot, owing to its almost-perfect semicircle of stars.

It is located at latitudes between 90 degrees and -50 degrees. Its boundaries were set by Belgian astronomer Eugène Delporte in 1930. A polygon of eight segments demonstrates the boundaries of the constellation. It is bordered by Boötes to the north and west. On the south, it borders Serpens Caput, and on the east, Hercules.

The constellation coordinates are 16h 00m 00s, +30° 00′ 00. It is at a right ascension of 15h 16m 03.8205s–16h 25m 07.1526s and a declination of 39.7117195°–25.5380573.

By Till Credner - Own work: AlltheSky.com

Mythology

Corona Borealis is an ancient constellation but many cultures have stories associated with it. In some cultures it is depicted as an eagle’s nest, while in others a bear’s den.

Celtic mythology relates the constellation to the castle Caer Arianrhod which was the home of mythical lady Arianrhod, Celtic goddess of fertility, rebirth, moon, time and fate.

In Greek mythology, the constellation represented the crown of King Minos’ daughter, Ariadne. Her father unleashed the fearsome Minotaur on Theseus, King of Athens in the celebrated labyrinth of Crete. He fought against the creature and killed him. Ariadne helped Theseus escape from the labyrinth. They got married, and Theseus gave her a crown at their wedding. The mythology narrates that the crown was made by the supreme goldsmith of the gods, Hephaestus, the god of fire, and was studded with jewels from India. In another narration, the crown was bestowed by the sungod Dionysos. During his nuptials in the island of Naxos, he gave the crown to his consort Ariadne.

The ancient Chinese astronomers created a chart with a loop of nine stars from Pi Coronae Borealis to Rho Coronae Borealis. They called this chart “Guansuo” which was considered the prison for working-class miscreants.

Major Stars in Corona Borealis Constellation

Corona Borealis constellation has seven stars. The brightest star in the constellation is called Alpha Coronae Borealis (α CrB) with a 2.2 magnitude. The rest of the stars are 4th-magnitude stars. These include Theta, Beta, Gamma, Delta, Epsilon and Iota Coronae Borealis.

Alpha Coronae Borealis

Alpha Coronae Borealis, also known as Alphecca or Gemma is a blue-white star in the Corona Borealis constellation. It is a binary system and its sequence stars orbit around each other in an eccentric orbit every 17.36 days.

Alpha Coronae Borealis is located 75 light years from the Sun. Its primary component is a white main sequence star which is 2.6 times the mass of the Sun.

Theta Coronae Borealis

Theta Coronae Borealis is composed of two components: Theta Coronae Borealis A and Theta Coronae Borealis B. It is a binary star system in the Corona Borealis constellation, located around 375 light years from the Earth.

The apparent visual magnitude of Theta Coronae Borealis is 4.13 and an absolute magnitude of −1.16.

It is believed that the star is 85 million years old and after many million years, the composition stars will cool down and their core hydrogen will be completely used. The stars will then become red giants (luminous giant stars).

Beta Coronae Borealis

Beta Coronae Borealis has two components: Beta Coronae Borealis A and Beta Coronae Borealis B. Being the second brightest star in the constellation, Beta Coronae Borealis can be spotted with naked eye. It is located 112 light-years from the Sun.

Although visible as one star from naked eye, Beta Coronae Borealis is actually two stars. The official name of Beta Coronae Borealis A is Nusakan, derived from Arabic. It means “The Two Lines” owing to its northern and southern lines in Hercules and Serpens. In Chinese Beta Coronae Borealis is named Guàn Suǒ sān meaning the “Third Star of Coiled Thong”.

Gamma Coronae Borealis

Gamma Coronae Borealis makes up the constellation’s outline. Similar to Beta Coronae Borealis, it also appears as one star but in reality there are two. Composed of Gamma A and Gamma B, the stars are quite difficult to tell apart through a telescope.

The star has an apparent visual magnitude of 3.83 and absolute magnitude of +0.56. Gamma Coronae Borealis stars are located at a distance of 145 light years and the radius of Gamma Coronae Borealis is estimated to be 2.79 times bigger than the Sun.