In astronomy, blitzars are a hypothetical type of neutron star, specifically pulsars that can rapidly collapse into black holes if their spinning slows down. Heino Falcke and Luciano Rezzolla[1] proposed these stars in 2013 as an explanation for fast radio bursts.[2]


These stars, if they exist, are thought to start from a neutron star with a mass that would cause it to collapse into a black hole if it were not rapidly spinning. Instead, the neutron star spins fast enough so that its centrifugal force overcomes gravity. This makes the neutron star a typical but doomed pulsar whose strong magnetic field radiates energy away and slows its spin.

Eventually the weakening centrifugal force is no longer able to halt the pulsar from collapsing into a black hole. At that moment, part of the pulsar's magnetic field outside the black hole is suddenly cut off from its vanished source. This magnetic energy is instantly transformed into a burst of wide spectrum radio energy.[5] As of January 2015, seven[6] radio events detected so far might represent such possible collapses; they are projected to occur every 10 seconds within the observable universe.[5] Because the magnetic field had previously cleared the surrounding space of gas and dust, there is no nearby material that will fall into the new black hole. Thus there is no burst of X-rays or gamma rays that usually happens when other black holes form.[5]

If blitzars exist, they may offer a new way to observe details of black hole formation.[7]


  1. ^ "Afscheidsgroet van een stervende ster" (Press release) (in Dutch). Nijmegen, NL: Radboud University. 4 July 2013. Retrieved 26 July 2015.[permanent dead link]
  2. ^ Heino Falcke; Luciano Rezzolla (2014). "Fast radio bursts: The last sign of supramassive neutron stars". Astronomy & Astrophysics. 562: A137. arXiv:1307.1409. Bibcode:2014A&A...562A.137F. doi:10.1051/0004-6361/201321996. S2CID 32284857.
  3. ^ "Mysterious radio flashes may be farewell greetings from massive stars collapsing into black holes". ScienceDaily (Press release). July 2013.
  4. ^ "Cosmic radio bursts point to cataclysmic origin". ScienceDaily (Press release). July 2013.
  5. ^ a b c Thornton, D.; Stappers, B.; Bailes, M.; Barsdell, B.; Bates, S.; Bhat, N.D.R.; et al. (5 July 2013). "A population of fast radio bursts at cosmological distances". Science. 341 (6141): 53–56. arXiv:1307.1628. Bibcode:2013Sci...341...53T. doi:10.1126/science.1236789. PMID 23828936. S2CID 206548502.
    For a popular summary see[3][4]
  6. ^ "Extremely short, sharp flash of radio waves from unknown source in the universe, caught as it was happening". ScienceDaily (Press release). 19 January 2015. Retrieved 3 March 2016.
  7. ^ Falcke, Heino; Rezzolla, Luciano. "Blitzars: Fast radio bursts from supramassive rotating neutron stars". Astronomy. Nijmegen, NL: Radboud University. Retrieved 8 July 2013.