The Triangulum Galaxy is a spiral galaxy 2.73 million light-years (ly) from Earth in the constellation Triangulum. It is catalogued as Messier 33 or NGC (New General Catalogue) 598. With the D25 isophotal diameter of 18.74 kiloparsecs (61,100 light-years), the Triangulum Galaxy is the third-largest member of the Local Group of galaxies, behind the Andromeda Galaxy and the Milky Way.
The Galactic Center is the rotational center, the barycenter, of the Milky Way galaxy. Its central massive object is a supermassive black hole of about 4 million solar masses, which is called Sagittarius A*, a compact radio source which is almost exactly at the galactic rotational center. The Galactic Center is approximately 8 kiloparsecs (26,000 ly) away from Earth in the direction of the constellations Sagittarius, Ophiuchus, and Scorpius, where the Milky Way appears brightest, visually close to the Butterfly Cluster (M6) or the star Shaula, south to the Pipe Nebula.
The Sombrero Galaxy (also known as Messier Object 104, M104 or NGC 4594) is a peculiar galaxy of unclear classification in the constellation borders of Virgo and Corvus, being about 9.55 megaparsecs (31.1 million light-years) from the Milky Way galaxy. It is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. It has a D25 isophotal diameter of approximately 29.09 kiloparsecs (94,900 light-years), making it slightly bigger in size than the Milky Way.
Messier 49 is a giant elliptical galaxy about 56 million light-years away in the equatorial constellation of Virgo. This galaxy was discovered by astronomer Charles Messier in 1777.
Messier 108 is a barred spiral galaxy about 28 million light-years away from Earth in the northern constellation Ursa Major. It was discovered by Pierre Méchain in 1781 or 1782. From the Earth, this galaxy is seen almost edge-on.
Cygnus X-3 is a high-mass X-ray binary (HMXB), one of the stronger binary X-ray sources in the sky. It is often considered to be a microquasar, and it is believed to be a compact object in a binary system which is pulling in a stream of gas from an ordinary star companion. It is one of only two known HMXBs containing a Wolf-Rayet star. It is invisible visually, but can be observed at radio, infrared, X-ray, and gamma-ray wavelengths.
NGC 2841 is an unbarred spiral galaxy in the northern circumpolar constellation of Ursa Major. It was discovered on 9 March 1788 by German-born astronomer William Herschel. J. L. E. Dreyer, the author of the New General Catalogue, described it as, "very bright, large, very much extended 151°, very suddenly much brighter middle equal to 10th magnitude star". Initially thought to be about 30 million light-years distant, a 2001 Hubble Space Telescope survey of the galaxy's Cepheid variables determined its distance to be approximately 14.1 megaparsecs or 46 million light-years. The optical size of the galaxy is 8.′1 × 3.′5.
NGC 4309 is a lenticular galaxy located about 55 million light-years away in the constellation Virgo. The galaxy was discovered by astronomer Christian Peters in 1881 and is a member of the Virgo Cluster.
NGC 89 is a barred spiral or lenticular galaxy, part of Robert's Quartet, a group of four interacting galaxies.
NGC 3169 is a spiral galaxy about 75 million light years away in the constellation Sextans. It has the morphological classification SA(s)a pec, which indicates this is a pure, unbarred spiral galaxy with tightly-wound arms and peculiar features. There is an asymmetrical spiral arm and an extended halo around the galaxy. It is a member of the NGC 3166 Group of galaxies, which is a member of the Leo II Groups, a series of galaxies and galaxy clusters strung out from the right edge of the Virgo Supercluster.
1E1740.7-2942, or the Great Annihilator, is a Milky Way microquasar, located near the Galactic Center on the sky. It likely consists of a black hole and a companion star. It is one of the brightest X-ray sources in the region around the Galactic Center.
NGC 3862 is an elliptical galaxy located 300 million light-years away in the constellation Leo. Discovered by astronomer William Herschel on April 27, 1785, NGC 3862 is an outlying member of the Leo Cluster.
Sh2-297 is an emission nebula in the constellation Canis Major. The region was catalogued in 1959 in the extended seconded edition of the Sharpless catalogue. This area is part of the Canis Major OB1 Association, and is a very active area of new star formation.
NGC 5084 is a lenticular galaxy in the constellation of Virgo. It is located at a distance of circa 80 million light years from Earth, which, given its apparent dimensions, means that NGC 5084 is at least 200,000 light years across. It is one of the largest and most massive galaxies in the Virgo Supercluster. It was discovered by William Herschel on March 10, 1785. It is a member of the NGC 5084 Group of galaxies, which is a member of the Virgo II Groups, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. The galaxy is seen nearly edge-on, with inclination 86°, and features a warped disk and large quantities of HI gas extending along the disk, probably accumulated after multiple accretions of smaller galaxies.
NGC 6047 is an elliptical galaxy located about 430 million light-years away in the constellation Hercules. It was discovered by astronomer Lewis Swift on June 27, 1886. NGC 6047 is a member of the Hercules Cluster.
NGC 708 is an elliptical galaxy located 240 million light-years away in the constellation Andromeda and was discovered by astronomer William Herschel on September 21, 1786. It is classified as a cD galaxy and is the brightest member of Abell 262. NGC 708 is a weak FR I radio galaxy and is also classified as a type 2 Seyfert galaxy.
NGC 541 is a lenticular galaxy located in the constellation Cetus. It is located at a distance of circa 230 million light years from Earth, which, given its apparent dimensions, means that NGC 541 is about 130,000 light years across. It was discovered by Heinrich d'Arrest on October 30, 1864. It is a member of the Abell 194 galaxy cluster and is included in the Atlas of Peculiar Galaxies in the category galaxies with nearby fragments. NGC 541 is a radio galaxy of Fanaroff-Riley class I, also known as 3C 40A.
NGC 759 is an elliptical galaxy located 230 million light-years away in the constellation Andromeda. NGC 759 was discovered by astronomer by Heinrich d'Arrest on September 17, 1865. It is a member of Abell 262.
NGC 5846 is an elliptical galaxy located in the constellation Virgo. It is located at a distance of circa 90 million light years from Earth, which, given its apparent dimensions, means that NGC 5846 is about 110,000 light years across. It was discovered by William Herschel on February 24, 1786. It lies near 110 Virginis and is part of the Herschel 400 Catalogue. It is a member of the NGC 5846 Group of galaxies, itself one of the Virgo III Groups strung out to the east of the Virgo Supercluster of galaxies.
NGC 3665 is a lenticular galaxy located in the constellation Ursa Major. It is located at a distance of circa 85 million light-years from Earth, which, given its apparent dimensions, means that NGC 3665 is about 85,000 light years across. It was discovered by William Herschel on March 23, 1789.
