Galactic CenterThe Galactic Center is the barycenter of the Milky Way and a corresponding point on the rotational axis of the galaxy. Its central massive object is a supermassive black hole of about 4 million solar masses, which is called Sagittarius A*, part of which is a very compact radio source arising from a bright spot in the region around the black hole, near the event horizon.
Messier 38Messier 38 or M38, also known as NGC 1912 or Starfish Cluster, is an open cluster of stars in the constellation of Auriga. It was discovered by Giovanni Batista Hodierna before 1654 and independently found by Guillaume Le Gentil in 1749. The open clusters M36 and M37, also discovered by Hodierna, are often grouped together with M38. Distance is about 1.066 kpc (3,480 ly) away from Earth.
Messier 36Messier 36 or M36, also known as NGC 1960 or the Pinwheel Cluster, is an open cluster of stars in the somewhat northernAurigaconstellation. It was discovered by Giovanni Batista Hodierna before 1654, who described it as a nebulous patch. The cluster was independently re-discovered by Guillaume Le Gentil in 1749, then Charles Messier observed it in 1764 and added it to his catalogue. It is about 1,330 pc (4,340 light years) away from Earth.
Charles MessierCharles Messier (French:; 26 June 1730 – 12 April 1817) was a French astronomer. He published an astronomical catalogue consisting of 110 nebulae and star clusters, which came to be known as the Messier objects, referred to with the letter M and their number between 1 and 110. Messier's purpose for the catalogue was to help astronomical observers distinguish between permanent and transient visually diffuse objects in the sky.
Open clusterAn open cluster is a type of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and many more are thought to exist. Each one is loosely bound by mutual gravitational attraction and becomes disrupted by close encounters with other clusters and clouds of gas as they orbit the Galactic Center.
Galactic anticenterThe galactic anticenter is a direction in space directly opposite to the Galactic Center, as viewed from Earth. This direction corresponds to a point on the celestial sphere. From the perspective of an observer on Earth, the galactic anticenter is located in the constellation Auriga, and the Crab Nebula and the bright star Beta Tauri (Elnath) appear nearest this point.
Giovanni Battista HodiernaGiovanni Battista Hodierna, also spelled as Odierna (13 April 1597 – 6 April 1660) was an Italian astronomer at the court of Giulio Tomasi, Duke of Palma (Palma di Montechiaro). He compiled a catalogue of comets and other celestial objects containing some 40 entries, including at least 19 real and verifiable nebulous objects that might be confused with comets. BiographyHodierna was born in Ragusa, Sicily and died in Palma di Montechiaro.
EarthThird planet from the SunSurface equivalent doserate0.274 μSv/hAbsolute magnitude (H)−3.99AtmosphereSurface pressure101.325 kPa (at sea level)Composition by volume78.08% nitrogen (dry air)20.95% oxygen (dry air)≤1% water vapor (variable)0.9340% argon0.0430% carbon dioxide0.00182% neon0.00052% helium0.00017% methane0.00011% krypton0.00006% hydrogen Source:Earth is the third planet from the Sun and the only astronomical object known to harbor life.
ConstellationA constellation is an area on the celestial sphere in which a group of visible stars forms a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellations were likely defined in prehistory. People used them to relate stories of their beliefs, experiences, creation, and mythology.Guillaume Le GentilGuillaume Joseph Hyacinthe Jean-Baptiste Le Gentil de la Galaisière (French pronunciation: [ɡijom lə ʒɑ̃ti], 11 or 12 September 1725 – 22 October 1792) was a French astronomer who discovered several nebulae and was appointed to the Royal Academy of Sciences.
AurigaAuriga is a constellation in the northern celestial hemisphere. It is one of the 88 modern constellations; it was among the 48 constellations listed by the 2nd-century astronomer Ptolemy. Its name is Latin for '(the) charioteer', associating it with various mythological beings, including Erichthonius and Myrtilus. Auriga is most prominent during winter evenings in the northern Hemisphere, as are five other constellations that have stars in the Winter Hexagonasterism.
Robert Julius TrumplerRobert Julius Trumpler (October 2, 1886 – September 10, 1956) was a Swiss-Americanastronomer. CareerBorn in Switzerland on October 2, 1886, where Trumpler did initial schooling. Trumpler entered the Universität Zürich but later transferred to the University of Göttingen where he earned his PhD in 1910. In 1915, during World War I, he emigrated to the United States and joined the University of California, Berkeley.*As an Amazon Associate I earn from qualifying purchases.