Extragalactic cosmic ray Extragalactic cosmic ray Extragalactic cosmic rays are very-high-energy particles that flow into the Solar System from beyond the Milky Way galaxy. The energies these particles possess are in excess of 10 eV. Unlike solar or galactic cosmic rays, little is known about the origins of extragalactic cosmic rays. This is largely due to a lack of statistics: only about 1 extragalactic cosmic ray particle per square meter per year reaches the Earth's surface (see figure). There are many ideas about which processes may be responsible for cosmic rays with such high energies. In the 'bottom-up' approach, cosmic rays gain more
Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey CANDELS, the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, is the largest project in the history of the Hubble Space Telescope, with 902 assigned orbits (about two months) of observing time. It was carried out between 2010 and 2013 with two cameras on board Hubble – WFC3 and ACS – and aims to explore galactic evolution in the early Universe, and the very first seeds of cosmic structure at less than one billion years after the Big Bang. The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey is designed to document the first third