I point to an interesting similarity in the radio and the soft X-ray light curves between the 2009 November outburst of the X-ray binary Aquila X-1 and some solar flares. The ratio of the soft X-ray and radio luminosities of Aquila X-1 in that outburst is also similar to some weak solar flares, as is the radio spectrum near 8 GHz. Based on these as well as on some other recent studies that point to some similar properties of accretion disk coronae and stellar flares, such as the ratio of radio to X-ray luminosities, I speculate that the soft X-ray outburst of Aquila X-1 was related to a huge magnetic flare from its disk corona.
- Stars: flare
- X-rays: binaries