'Virgo' is one of the constellations of the zodiac. Its name is Latin for 'virgin'. Lying between Leo to the west and Libra to the east, it is the second largest constellation in the sky (after Hydra) and the largest constellation in the zodiac. 'Virgo' is prominent in the spring sky in the northern hemisphere, visible all night in March and April.

'Spica', designated 'Alpha Virginis', is the brightest object in the constellation of 'Virgo' and one of the 20 brightest stars in the night sky. 'Spica' is a close binary star whose components orbit each other every four days. They stay close together enough that they cannot be resolved as two stars through a telescope. The changes in the orbital motion of this pair results in a Doppler shift in the absorption lines of their respective spectra, making them a double-lined spectroscopic binary.

'Aldebaran' is the brightest star in the constellation of 'Taurus' (the bull) which is also a zodiacal constellation. 'Antares' is the brightest star in the constellation of 'Scorpius' (the scorpion) which is again a constellation of the zodiac. 'Gemma', also known as 'Alphecca', is the brightest star in the constellation of 'Corona Borealis' (the northern crown). 'Corona Borealis' is not a zodiacal constellation.

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