The origin and location of the 5 March 1979 gamma-ray burst

Gamma-ray bursts (GRBs) have been controversial since their discovery, mainly because of the absence of counterparts at any other wavelength that would help identify the nature of the astrophysical object associated with them; this in turn could determine their distances and luminosities, providing some constraints on their physical parameters. Perhaps the most controversial GRB is that of 5 March 1979, precisely because there is an accurate positional identification of this burst with a known astronomical object, the supernova remnant N49 in the Large Magellanic Cloud (LMC). Such an association would fix the distance at 55 kpc, and with the observed flux would require prodigious energy and luminosity from this GRB, casting doubt on theoretical grounds, on its distance and its physical association with the LMC. However, some Kosmos 856 observations may provide more direct evidence on energy released and hence give a decisive answer to this question. (author)