An international team of researchers using data from Arecibo Observatory and the Fermi Space Telescope have discovered what they call a “gamma-ray heartbeat” coming from a cosmic gas cloud.
The cloud is in the constellation Aquilla and “beats” in rhythm with a black hole 100 light-years away in a microquasar system known as SS 433. The results were published today in the journal
Voilà, here’s the puzzling discovery our last post referred to: A strange gamma-ray heartbeat from a cosmic gas cloud that pulsates in sync with a wobbling black hole. The black hole is part of a so-called microquasar. This consists of the black hole and a giant star orbiting each other, while the black hole constantly sucks matter from the star. This matter collects on an accretion disk before falling into the black hole. However, some of the matter does not fall into the black hole, but is hurled out into space in two narrow jets at the top and bottom. As the accretion disk does not lie exactly in the orbital plane of the two partners, it sways like a spinning top set at an angle, and with it the jets do so as well, describe spirals in space. In the same rhythm as the tumbling jets and accretion disk, the inconspicuous gas cloud about 100 light years away pulsates in gamma rays. This temporal correspondence that was revealed by ten years of data from @NASA’s Fermi gamma-ray space telescope suggests a direct connection, but it is not clear exactly how the microquasar drives the gamma-ray “heartbeat” of the gas cloud. Animation: The amazing @scicomlab for DESY #space#science#astro#astrophysics#astroparticlephysics#research#physics#gamma#ray#gammaray#space#telescope#cosmos#cosmic#discovery#research#scienceiscool
Scientists still do not fully know how the jets overcome the black hole’s pull and are emitted from the disc, and the current study presents a new question – how does the black hole power the gas cloud’s heartbeat?
The study’s researchers say further observations and theoretical work are needed, but one suggestion is that the cloud’s gamma-ray emissions are caused by the injection of the nuclei of hydrogen atoms, known as fast protons, that are produced at the end of the jets, or near the black hole.
“SS 433 continues to amaze observers at all frequencies and theoreticians alike. And it is certain to provide a testbed for our ideas on cosmic-ray production and propagation near microquasars for years to come,” Li said.