Category Astronomy/Space

This image composite shows the search for the supernova, nicknamed Refsdal, using the NASA/ESA Hubble Space Telescope. The image to the left shows a part of the the deep field observation of the galaxy cluster MACS J1149.5+2223 from the Frontier Fields program. The circle indicates the predicted position of the newest appearance of the supernova. To the lower right the Einstein cross event from late 2014 is visible. The image on the top right shows observations by Hubble from October 2015, taken at the beginning of observation program to detect the newest appearance of the supernova. The image on the lower right shows the discovery of the Refsdal Supernova on Dec. 11, 2015, as predicted by several different models. Credit: NASA & ESA and P. Kelly (University of California, Berkeley)

This artist’s conception shows a blazar — the core of an active galaxy powered by a supermassive black hole. The VERITAS array has detected gamma rays from a blazar known as PKS 1441+25. Researchers found that the source of the gamma rays was within the relativistic jet but surprisingly far from the galaxy’s black hole. The emitting region is at least a tenth of a light-year away, and most likely is 5 light-years away. Credit: M. Weiss/CfA

X-ray image of the XXL-South Field. Credit: ESA/XMM-Newton/XXL survey consortium/(S. Snowden, L. Faccioli, F. Pacaud)

Ritchey Crater, located near the Martian equator, has impact melt deposits containing clay minerals. Impact melt forms when rock melted during an impact cools and hardens. The clay minerals found within these deposits are very likely to have formed after the impact event. Most clay minerals on Mars are thought to have formed during the earliest Martian epoch, known as the Noachian. However, evidence from Ritchey crater and other post-Noachian craters, suggests that clay formation after the Noachian was not uncommon. Credit: NASA/JPL/University of Arizona/Brown University