... galaxies . ... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Dave's Universe . ... An old galaxy cluster discovered in the young universe . ... The results showed that we are indeed seeing a galaxy cluster, as it was when the universe was about 3 billion years old т?? less than one-quarter of its current age. ... This is another sign of a mature galaxy cluster held firmly together by its own gravity, as young clusters have not had time to trap hot gas in this way...