AHEAD

On February 2 NASA’s satellite, Swift, was hit by cosmic gamma rays. This triggered an alert and seconds later University of WA’s Zadko Telescope swung into robotic action to take images and record the entire evolution of the event. The event appeared as a rapid brightening visible in the sky for a brief period of time. Its brightness was equivalent to millions of stars shining together from the same location. What was actually detected is known as a Gamma Ray Burst.

A star is disrupted violently when it wanders in the vicinity of a supermassive black hole. Until today, we have observed only a few of these events. Now astronomers say that they can predict where the next stellar disruption will happen, as they found the type of galaxy these events prefer.

Astronomers built a virtual telescope by linking a large array of radio receivers around the world. The telescope is called “Event Horizon Telescope” and will observe for the first time the “edge” of the black hole at the centre of our galaxy.

Using NuSTAR and ESA’s XMM-Newton telescope, astrophysicists observed, for the first time, winds from a nearby black hole to change temperatures rapidly.

Astronomers used NuSTAR to observe the brightest pulsar that has ever been detected. The source is located about 50 million light years away from Earth and in one second it emits as much energy as our sun in three and a half years.

Astrophysicists used three X-ray satellites to discover a giant black hole ripping apart a star and its remains for about a decade. This is the longest by far observation of a star’s death by a black hole.

  ΔΕΛΤΙΟ ΤΥΠΟΥ   Το πρόγραμμα AHEAD (Integrated Activities in the High–Energy Astrophysics Domain) του Εθνικού Αστεροσκοπείου Αθηνών είναι στην ευχάριστη θέση να ανακοινώσει ότι η ταινία θόλου, με τίτλο «The Hot and Energetic Universe» και σκηνοθέτη τον Θεοφάνη Ματσόπουλο, Read More …

Astrophysicists combined data from the world’s biggest observatories to study what happens to matter that is swept up by the merger of two colliding galaxy clusters.

Astronomers used NASA’s Chandra X-ray Observatory to obtain the deepest X-ray image we have ever observed. It took 7Ms or equivalently eleven and a half weeks of observing time to construct this amazing picture.

A very important process in observational astronomy is to carefully subtract the background noise from an image taken by an X-ray telescope. This background noise may come from background photons, i.e., photons not associated with the source that is being observed or artefacts from the telescope itself. For that purpose, scientists develop software tools that are used to analyse observations taken by X-ray telescopes.