Comments on early space controversies
DOI: 10.1063/pt.ghuj.rowp
When reading David Cummings and Louis Lanzerotti’s article on “Early debates in space science ” (Physics Today, February 2025, page 38), I was surprised to see their account of the solution to the mystery of where gamma-ray bursts come from.
Cummings and Lanzerotti mention the 1995 debate, held at the Smithsonian Institution’s National Museum of Natural History, on whether gamma-ray bursts are galactic or extragalactic. They state that the debate “did not resolve the dispute” but rather a “combination of space- and ground-based observations two years later did.” The authors mention Jan van Paradijs and his students, who in 1997 “were able to associate a gamma-ray burst with a specific galaxy” but unable to measure its emission-line spectra. They also mention a group led by Mark Metzger, who found a gamma-ray burst that occurred simultaneously with an optical flash, and resulting measurements “established beyond doubt that the burst sources were outside our galaxy.”
The article does not mention that it was the Italian–Dutch satellite BeppoSAX that detected and promptly, and accurately, localized a gamma-ray burst that occurred on 28 February 1997. In addition, with the same satellite, it was possible to discover the first x-ray counterpart of a gamma-ray burst event. 1 The BeppoSAX team, of which I was one of the leaders, rapidly distributed the event coordinates in the International Astronomical Union circular. That made it possible for Jan van Paradijs and colleagues to discover an optical transient that had a position consistent with the gamma-ray burst x-ray counterpart. 2
Also, the determination of the first gamma-ray-burst redshift by Metzger’s group 3 was the result of the BeppoSAX’s detection and prompt, accurate localization of another event, GRB 970508. With the same satellite, it was also possible to discover its x-ray counterpart (that is, its x-ray afterglow). 4 And thanks to the prompt alert of our collaborators in Caltech, led by Shri Kulkarni, and those at the Very Large Array radio telescope, led by Dale Frail, it was possible to discover the optical and radio counterparts and to measure its redshift. 3 , 5
For a more extended history of these discoveries, see my recently published review in reference .
References
1. E. Costa et al., Nature 387, 783 (1997). https://doi.org/10.1038/42885
2. J. van Paradijs et al., Nature 386, 686 (1997). https://doi.org/10.1038/386686a0
3. M. R. Metzger et al., Nature 387, 878 (1997). https://doi.org/10.1038/43132
4. L. Piro et al., Astron. Astrophys. 331, L41 (1998).
5. D. A. Frail et al., Nature 389, 261 (1997). https://doi.org/10.1038/38451
6. F. Frontera, Universe 10, 260 (2024). https://doi.org/10.3390/universe10060260
More about the Authors
Filippo Frontera. (filippo.frontera@unife.it) University of Ferrara, Ferrara, Italy.
