Using the Near Infrared Camera and Multi-Object Spectrometer onboard of the Hubble NASA/ESA Hubble Space Telescope, astronomers have made observations of young, surprisingly compact galaxies, each only 5000 light-years across, but weighing 200 thousand million times the mass of the Sun.
Extremely Compact Massive Galaxies at 1.7 < z < 3
One of the most exciting discoveries in extragalactic astronomy in the last few years is that massive (M ≥ 1011M⊙) galaxies at z > 1 were extremely compact ( [1]; [2]). Since these objects are not found in the local Universe ( [3]) it is clear that significant growth in the sizes of these galaxies has occurred during cosmic history.
