The Hubble Space Telescope photographed the lenticular galaxy NGC 3156. (NASA)
Text/Reporter Chen Juncun
NASA’s Hubble Space Telescope captured a fantastic image of a lens-like galaxy giving it a foggy appearance.
NASA recently released this picture. The lenticular galaxy, named NGC 3156, is located in the small southern constellation Sextans, about 73 million light-years away from Earth.
British astronomer William Herschel discovered NGC 3156 in 1784. Herschel is famous for his discovery of Uranus.
NGC 3156 has two visible lanes of dark reddish-brown dust running through the galaxy’s disk. Named for its lens-like appearance when viewed from the side or edge, this type of galaxy is somewhere between an elliptical galaxy and a spiral galaxy, sharing properties of both.
Like spiral galaxies, lenticular galaxies have a central bump of stars surrounded by a large disk. They often have spiral dark dust lanes but no large spiral arms. Like elliptical galaxies, lenticular galaxies contain mostly older stars and few stars that are still forming.
Astronomers have studied NGC 3156 in many ways, including studying newly formed stars and stars in the process of being destroyed by its central supermassive black hole. Using data from the Hubble Space Telescope, they compared stars near the galaxy’s core with stars in other galaxies with similar-sized black holes. They found that NGC 3156 had a higher-than-average proportion of stars swallowed by supermassive black holes compared to its peers.
As for the sextant constellation where NGC 3156 is located, it is a constellation named after the sextant (an instrument for measuring the height of stars) and belongs to the Hercules family. A constellation family is a group of different constellations in the same area.
The sextant was invented in the 18th century and is often seen as an instrument for navigation, but it is also used in astronomy. However, in modern astronomy, sextants are no longer used. This instrument has been replaced by instruments that more accurately measure the positions of stars and celestial bodies. ◇
