The lives of massive stars are characterized by companionship: these stars are almost always found in gravitationally bound pairs. As such massive binaries evolve further, their cores run out of nuclear fuel and the stars can explode as supernovae, leaving behind in their centers either a neutron star or a black hole. In most cases such an explosion would be fatal for the binary, and disrupt it. In some cases, however, the final phases of binary stellar evolution can produce two compact objects -either white dwarfs, neutron stars or black … Continue Reading ››
Former OKC postdoc, Giorgos Leloudas, along with OKC co-investigators suggests a new interpretation for an event which was previously classified as the most luminous supernova ever seen. They argue that the event is a star being ripped apart by the supermassive black hole at the center of a galaxy.
Black holes leave their marks all over the observed universe. They do however also inspire new and exciting ideas about space and time itself, both in the micro-cosmos and on the large scales of the universe.
It seems that nearly exactly 100 years after their prediction by Albert Einstein, Gravitational Waves have finally been directly detected for the first time. Speakers of the LIGO experiment announced yesterday that they have witnessed the final stages of the inspiral and merger of a massive black hole binary system. This marks the beginning of a new type of astronomy with gravitational waves that allows to explore a so-far completely unknown side of the Universe.
On April 27th this year, an e-mail alert was sent around signifying the detection of yet another GRB. Yet this event was like no other challenging all our models.
The discovery of a black hole enjoying a feeding frenzy in our nearest neighbor galaxy, Andromeda, has provided new insights into a mysterious class of extreme astrophysical objects called “ultraluminous X-ray sources”.
It isn’t unusual for material falling into a black hole to generate copious X-ray emission, but ultraluminous X-ray sources are so bright that they sometimes outshine their entire host galaxy in the X-ray band. Astronomers have spent years debating the nature of these enigmatic objects and two main scenarios have emerged. Either ultraluminous X-ray sources are unusually massive black … Continue Reading ››