Magnitude +10.4 globular cluster NGC 1854 (α=05h 09m 20.2s, δ=-68° 50′ 56″ J2000.0) was discovered in 1826 by James Dunlop. It lies 135,000 light-years away in the Large Magellanic Cloud. This Hubble Space Telescope view is just 2.4 x 1.5 arcminutes in size. Click the image for a larger version. Image credit: ESA/Hubble & NASA.This NASA/ESA Hubble Space Telescope image shows the globular cluster NGC 1854, a gathering of white and blue stars in the southern constellation of Dorado (The Dolphinfish). NGC 1854 is located about 135,000 light-years away, in the Large Magellanic Cloud (LMC), one of our closest cosmic neighbours and a satellite galaxy of the Milky Way.
The LMC is a hotbed of vigorous star formation. Rich in interstellar gas and dust, the galaxy is home to approximately 60 globular clusters and 700 open clusters. These clusters are frequently the subject of astronomical research, as the Large Magellanic Cloud and its little sister, the Small Magellanic Cloud, are the only systems known to contain clusters at all stages of evolution. Hubble is often used to study these clusters as its extremely high-resolution cameras can resolve individual stars, even at the clusters’ crowded cores, revealing their mass, size and degree of evolution.
By pushing the NASA/ESA Hubble Space Telescope to its limits, astronomers have shattered the cosmic distance record by measuring the distance to the most remote galaxy ever seen in the universe. The galaxy, named GN-z11, has a redshift of 11.1, which corresponds to 400 million years after the Big Bang when the universe was only three percent of its current age.
Using data from NASA’s Fermi Gamma-ray Space Telescope and other facilities, an international team has found the first gamma-ray binary in another galaxy and the most luminous one ever seen. The dual-star system, dubbed LMC P3, contains a massive star and a crushed stellar core that interact to produce a cyclic flood of gamma rays.
Galaxy clusters are often described by superlatives. After all, they are huge conglomerations of galaxies, hot gas, and dark matter, representing the largest structures in the universe held together by gravity. New observations of the galaxy cluster SPT-CLJ2344-4243 (or Phoenix Cluster) at X-ray, ultraviolet, and optical wavelengths are helping astronomers better understand this extraordinary system.
