SpaceTime

Image: X-rays from Chandra in blue and infrared emission from the Hubble Space Telescope in red and yellow. The inset shows a close-up view of Sgr A* in X-rays only, covering a region half a light year wide. The diffuse X-ray emission is from hot gas captured by the black hole and being pulled inwards. This hot gas originates from winds produced by a disk-shaped distribution of young massive stars observed in infrared observations. Credit: X-ray: NASA/UMass/D.Wang et al., IR: NASA/STScI Within the central tenth of a parsec in the middle of our galaxy there is a concentration of young stars (S-stars) that interact with a supermassive black hole Sagittarius A* (Sgr A*).

These two false-color images compare the distribution of normal matter (red, left) with dark matter (blue, right) in the universe. The brightness of clumps corresponds to the density of mass. The comparison will provide insight on how structure formed in the evolving universe under the relentless pull of gravity. Credit: NASA, ESA, CalTech Gamma-ray bursts (GRBs) are the most luminous explosive events in the cosmos, which can be detected even out to the edge of the Universe and they can be used to probe the properties of the high-z Universe, including high-z star formation history.

Image: Crab nebula as seen by Chandra. Credit: NASA/CXC/SAO/F. Seward et al. In the center of several supernova remnants there are pulsars with significantly lower values of the dipolar magnetic field than the average radio-pulsar population (10^{ 12 }G). A possible explanation requires the slow rotation of the proto-neutron star at birth, which is unable to amplify its magnetic field to typical pulsar levels.

Image Credit: NASA/Goddard Space Flight Center Radio emission of radio-quiet quasars may be due to stars formation in the quasar host galaxy, to a jet launched by the supermassive black hole, or to relativistic particles accelerated in a wide-angle radiatively-driven outflow.