Aquila X-1

L. J. Kaluzienski and S. S. Holt, Goddard Space Flight Center, report the detection of an x-ray outburst from a position consistent with that (i.e., within the ~ 2o error circle) of the recurrent transient Aql X-1. Observations with the Ariel-5 all-sky monitor in the instrument coarse-spatial-resolution mode indicate that this latest flare may have commenced as early as Mar. 14, the flux (3-6 keV) remaining at a relatively low level (<~ 0.2 Crab) through Mar. 19. The source apparently brightened to a level of 0.3-0.4 Crab on Mar. 20, and fine-mode observations on Mar. 26 and 27 indicate an intensity of ~ 0.5 Crab. It is noted that the last flare observed from this source occurred in 1978 June (IAUC 3235).