A nebula from Latin: "cloud"is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, nebula was a name for any diffuse astronomical object, including galaxies beyond the Milky Way.
The Antennae galaxies, located about 62 million light-years from Earth. This composite image includes images from the Chandra X-ray Observatory (blue), the Hubble Space Telescope (gold and brown), and the Spitzer Space Telescope (red).
Four new Earth-sized exoplanets have been discovered orbiting a star about 40 light-years away - and each may contain liquid water and be able to sustain life, astronomers from NASA and the European Southern Observatory said Wednesday. A Belgian-led team was able to spy these planets using space- and ground-based telescopes as they passed in front of their host, a red dwarf star known as TRAPPIST-1.
Pismis located at the core of small open star cluster Pismis can be seen in this image provided by NASA and ESA. The star cluster Pismis 24 lies in the core of the large emission nebula NGC 6357 that extends on the arm of the Sagittarius constellation.