Messier 23, also known as NGC 6494, is an open cluster of stars in the northwest of the southern constellation of Sagittarius. It was discovered by Charles Messier in 1764. It can be found in good conditions with binoculars or a modestly sized telescope. It is in front of "an extensive gas and dust network", which there may be no inter-association. It is within 5° the sun's position so can be occulted by the moon.
Phi Aurigae, Latinized from φ Aurigae, is a giant star in the northern constellation of Auriga. It is faintly visible to the naked eye with an apparent visual magnitude of 5.089. It lies 10′ from another faint naked-eye star HD 35520, between the three open clusters M36 and M38, and NGC 1893.
NGC 6530 is a young open cluster of stars in the southern constellation of Sagittarius, located some 4,300 light years from the Sun. It exists within the H II region known as the Lagoon Nebula, or Messier 8, and spans an angular diameter of 14.0′. The nebulosity was first discovered by G. B. Hodierna prior to 1654, then re-discovered by J. Flamsteed circa 1680. It was P. Loys who classified it as a cluster in 1746, as he could only resolve stars. The following year, G. Le Gentil determined it was both a nebula and a cluster.
R Coronae Australis is a variable binary system in the constellation Corona Australis. It has varied between magnitudes 10 and 14.36. A small reflection/emission nebula NGC 6729 extends from the star towards SE. It is also the brightest feature of the Coronet Cluster, therefore sometimes called R CrA Cluster.
HD 142415 is a single star in the southern constellation of Norma, positioned next to the southern constellation border with Triangulum Australe and less than a degree to the west of NGC 6025. With an apparent visual magnitude of 7.33, it is too faint to be visible to the naked eye. The distance to this star is 116 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −12 km/s. It is a candidate member of the NGC 1901 open cluster of stars.
NGC 4349-127 is a probable red giant approximately 6,100 light-years away in the constellation of Crux. As a member of the open cluster NGC 4349, it is located about 2000 parsecs from the Sun. Its mass is estimated at 3.9 times Solar, and its age is about 200 million years.
Kappa Crucis is a spectroscopic binary star in the open cluster NGC 4755, which is also known as the Kappa Crucis Cluster or Jewel Box Cluster.
S Monocerotis, also known as 15 Monocerotis, is a massive multiple and variable star system located in the constellation Monoceros. It is the brightest star in the Christmas Tree open cluster in the area catalogued as NGC 2264.
c Puppis, also known as HD 63032 and HR 3017, is a spectroscopic binary star in the constellation Puppis. Its apparent magnitude is 3.61. Located around 347 parsecs (1,130 ly) distant, the primary is an orange-red bright giant or supergiant of spectral type K2.5Ib-IIa or K5IIa, while the secondary, discovered in 1983, is a blue main-sequence star of spectral type B9V. The system is the brightest member of the open cluster NGC 2451, over two magnitudes brighter than every other star in the cluster. As the turnoff point of the cluster is currently around B7, the parameters of the system fit with cluster membership.
YBP 1194 is a G-type main-sequence star, class G5V, in the open cluster M67 in the constellation Cancer. It is the best solar twin found to date, having the near exact temperature and mass as the Sun. YBP 1194 has a higher metallicity than the Sun and is 0.5 billion years younger at an age of 4.2 billion years old, but due to the distance, the error bar is high at ±1.6 billion years. On December 19, 2013, it was announced to have an extrasolar planet with a period of 6.9 days and a high eccentricity of 0.24 with a mass of 0.34 MJ. It is about 2,772 light-years from the Sun. It is packed in a small cluster, Messier 67, with a radius of 10 ly, with over 500 other stars. For comparison, the Sun has 17 stars at a distance of 10 ly and about 134 stars at a distance of 20 ly.
HR 4887 is a suspected variable star in the open cluster NGC 4755, which is also known as the Kappa Crucis Cluster or Jewel Box Cluster.
DS Crucis is a variable star near the open cluster NGC 4755, which is also known as the Kappa Crucis Cluster or Jewel Box Cluster. It is in the constellation Crux.
NGC 2539 is an open cluster in the constellation Puppis, located at the north edge of the constellation. It was discovered by William Herschel on January 31, 1785. It is a moderately rich cluster and with little central concentration, with Trumpler class II1m.
NGC 4349 is an open cluster in the constellation Crux. It was discovered by James Dunlop in 1826. It is located approximately 7,000 light years away from Earth.
NGC 4103 is an open cluster in the constellation Crux. It was discovered by James Dunlop in 1826. It is located approximately 5,000 light years away from Earth, in the Carina-Sagittarius arm.
NGC 4815 is an open cluster in the constellation Musca. It was discovered by John Herschel in 1834. It is located approximately 10,000 light years away from Earth.
NGC 7160 is an open cluster in the constellation Cepheus. It was discovered by William Herschel on November 9, 1789. The cluster was also observed by John Herschel on October 7, 1829. It is a poor cluster and with little central concentration, with Trumpler class II3p. It is part of the stellar association Cepheus OB2, located one degree south-southwest of VV Cephei.
HD 193322 is a group of six stars which appear to be at least loosely bound into a system in the constellation Cygnus. The stars comprise the core of the young open cluster Collinder 419, which contains a total of 51 known stars. Another prominent member of the cluster is the eclipsing binary star V470 Cygni. The cluster lies at a distance of about 3500 light years and its stars are only a few million years old.
NGC 1570, mistakenly called NGC 1571, is a faint galaxy located in the southern constellation Caelum, the chisel. It has a blue magnitude of 13.2, making it visible through a medium sized telescope. Based on a redshift of z = 0.014760, the object is estimated to be 198 million light years away from the Local Group. It appears to be receding with a heliocentric radial velocity of 4,392 km/s.
