A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. The name of this category of star cluster is derived from the Latin globulus—a small sphere. A globular cluster is sometimes known more simply as a globular.
Messier 4 or M4 (also designated NGC 6121) is a globular cluster in the constellation of Scorpius. It was discovered by Philippe Loys de Chéseaux in 1746 and catalogued by Charles Messier in 1764. It was the first globular cluster in which individual stars were resolved.
Messier 14 (also known as M14 or NGC 6402) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier in 1764. At a distance of about 30,000 light-years, M14 contains several hundreds of thousands of stars. At an apparent magnitude +7.6 it can be easily observed with binoculars. Medium-sized telescopes will show some hint of the individual stars of which the brightest is of magnitude +14.
Messier 5 or M5 (also designated NGC 5904) is a globular cluster in the constellation Serpens. It was discovered by Gottfried Kirch in 1702. It should not be confused with the much fainter and more distant globular cluster Palomar 5, which is situated nearby in the sky.
Globular Cluster M107 (also known as Messier Object 107 or NGC 6171) is a very loose globular cluster in the constellation Ophiuchus. It was discovered by Pierre Méchain in April 1782 and independently by William Herschel in 1793. It wasn't until 1947 that Helen Sawyer Hogg added it and three other objects discovered by Méchain to the list of Messier objects. M107 is close to the galactic plane at a distance of about 20,900 light-years from Earth.
Omega Centauri or NGC 5139 is a globular cluster seen in the constellation of Centaurus, discovered by Edmond Halley in 1677 who listed it as a nebula. Omega Centauri had been listed in Ptolemy's catalog 2000 years ago as a star. Lacaille included it in his catalog as number I.5. It was first recognized as a globular cluster by the English astronomer John William Herschel in the 1830s.
Messier 3 (also known as M3 or NGC 5272) is a globular cluster in the constellation Canes Venatici. It was discovered by Charles Messier in 1764, and resolved into stars by William Herschel around 1784. This cluster is one of the largest and brightest, and is made up of around 500,000 stars. It is located at a distance of about 33,900 light-years away from Earth. M3 has an apparent magnitude of 6.2, making it visible to the naked eye under dark conditions.
Messier 72 (also known as M72 or NGC 6981) is a globular cluster in the Aquarius constellation discovered by Pierre Méchain in August 29, 1780. Charles Messier looked for it on the following October 4 and 5, and included it in his catalog. Both decided that it was a faint nebula rather than a cluster.
NGC 6397 is a globular cluster in the Ara constellation. It is located about 7,200 light-years from Earth, making it one of the two nearest globular clusters to Earth (the other one being Messier Object 4). The cluster contains around 400,000 stars. NGC 6397 is one of the at least 20 globulars of our Milky Way Galaxy which have undergone a core collapse, meaning that its core has contracted to a very dense stellar agglomeration.
Messier 2 or M2 (also designated NGC 7089) is a globular cluster in the constellation Aquarius, five degrees north of the star Beta Aquarii. It was discovered by Jean-Dominique Maraldi in 1746 and is one of the largest known globular clusters.
Messier 80 (also known as M80 or NGC 6093) is a globular cluster in the constellation Scorpius. It was discovered by Charles Messier in 1781. M80 is located midway between α Scorpii and β Scorpii in a field in the Milky Way that is rich in nebulae. It can be viewed with modest amateur telescopes as a mottled ball of light. With an apparent diameter of about 10' and at an estimated distance of 32,600 light-years, M80's spatial diameter is about 95 light-years.
Messier 9 or M9 (also designated NGC 6333) is a globular cluster in the constellation of Ophiuchus. It was discovered by Charles Messier in 1764. M9 is one of the nearer globular clusters to the center of the Milky Way Galaxy with a distance of around 5,500 light-years. Its distance from Earth is 25,800 light-years. The total luminosity of this cluster is around 120,000 times that of the Sun, the absolute magnitude being -8.04.
Messier 10 or M10 (also designated NGC 6254) is a globular cluster in the constellation of Ophiuchus. The object was discovered by Charles Messier on May 29, 1764, who cataloged it as number 10 in his list. He described it as a "nebula without stars", but later study revealed it as a globular cluster of thousands of stars. M10 has an apparent diameter of some 20 arcminutes, about two-thirds of the apparent diameter of the Moon.
Messier 12 or M 12 (also designated NGC 6218) is a globular cluster in the constellation of Ophiuchus. It was discovered by Charles Messier on May 30, 1764. Located roughly 3° in the sky from the cluster M10, M12 is about 16,000 light-years from Earth and has a spatial diameter of about 75 light-years. The brightest stars of M12 are of 12th magnitude. It is rather loosely packed for a globular and was once thought to be a tightly concentrated open cluster.
Messier 15 or M15 (also designated NGC 7078) is a globular cluster in the constellation Pegasus. It was discovered by Jean-Dominique Maraldi in 1746 and included in Charles Messier's catalogue of comet-like objects in 1764. At an estimated 13.2 billion years old, it is one of the oldest known globular clusters. M15 is about 33,600 light-years from Earth. It has an absolute magnitude of -9.2 which translates to a total luminosity of 360,000 times that of the Sun.
Messier 19 or M19 (also designated NGC 6273) is a globular cluster in the constellation Ophiuchus. It was discovered by Charles Messier in 1764 and added to his catalogue of comet-like objects that same year. M19 is the most oblate of the known globular clusters. It is at a distance of about 28,000 light-years from the Solar System, and is quite near to the Galactic Center, at only about 5,200 light-years away.
Messier 22 (also known as M22 or NGC 6656) is an elliptical globular cluster in the constellation Sagittarius, near the Galactic bulge region. It is one of the brightest globulars that is visible in the night sky.
Messier 28 (also known as M28 or NGC 6626) is a globular cluster in the constellation Sagittarius. It was discovered by Charles Messier in 1764. M28 is at a distance of about 18,000 to 19,000 light-years away from Earth. 18 RR Lyrae type variable stars have been observed in this cluster. In 1986, M28 became the first globular cluster where a millisecond pulsar was discovered.
Messier 30 (also known as M30 or NGC 7099) is a globular cluster in the Capricornus constellation. It was discovered by Charles Messier in 1764. M30 is at a distance of about 28,000 light-years away from Earth, and about 90 light-years across.
Messier 54 (also known as M54 or NGC 6715) is a globular cluster in the constellation Sagittarius. It was discovered by Charles Messier in 1778 and subsequently included in his catalog of comet-like objects.
Messier 53 (also known as M53, or NGC 5024) is a globular cluster in the Coma Berenices constellation. It was discovered by Johann Elert Bode in 1775. M53 is one of the more outlying globular clusters, being about 60,000 light-years away from the Galactic Center, and almost the same distance (about 58,000 light-years) from the Solar system. named the maurice pullen star
Messier 55 (also known as M55 or NGC 6809) is a globular cluster in the constellation Sagittarius. It was discovered by Nicolas Louis de Lacaille in 1751 and catalogued by Charles Messier in 1778. M55 is at a distance of about 17,300 light-years away from Earth. Only about half a dozen variable stars have been discovered in M55.
Messier 56 (also known as M56 or NGC 6779) is a globular cluster in the constellation Lyra. It was discovered by Charles Messier in 1779. M56 is at a distance of about 32,900 light-years from Earth and measures roughly 84 light-years across. The brightest stars in M56 are of 13th magnitude while it contains only about a dozen known variable stars, such as V6 or V1; other variable stars are V2 (irregular) and V3 (semiregular).
Messier 62 (also known as M62 or NGC 6266) is a globular cluster in the constellation Ophiuchus. It was discovered in 1771 by Charles Messier. M62 is at a distance of about 22,500 light-years from Earth and measures some 100 light-years across. From studies conducted in the 1970s it is known that M62 contains the high number of 89 variable stars, many of them of the RR Lyrae type.