SIMBAD references

M. F. Corcoran, Universities Space Research Association and Goddard Space Flight Center, reports: "A May 26 observation by the Rossi X-ray Timing Explorer Proportional Counter Array (RXTE PCA) of the peculiar luminous star eta Car shows that the 2-10-keV x-ray flux was approximately 2.7 x 10**-10 erg s**-1 cm**-2, corresponding to an x-ray luminosity of about 6.5 x 10**34 erg/s for a distance of 2100 pc. This is the highest x-ray flux yet observed for eta Car. Monitoring observations with the RXTE PCA show that the star has undergone four x-ray maxima since Mar. 2003. Three of the x-ray peaks are separated by about 22 days, though the shortest separation is only 12 days. A straight-line fit to three of the four recent peaks, and a linear extrapolation of the rise in brightness since the most recent x-ray minimum on May 9, suggests that the x-ray flux will reach a maximum near 3 x 10**-10 erg s**-1 cm**-2 near May 31. Based on eta Car's 2020-day periodicity (Damineli et al. 2000, Ap.J. 528, L101), this will probably be the maximum brightness of the star during this current cycle, and we expect that the x-ray eclipse ingress (Ishibashi et al. 1999, Ap.J. 524, 983) to begin shortly thereafter. If so, and if the x-ray flux declines at a similar rate to the 1997 eclipse ingress, then the x-ray minimum will occur near 2003 July 24."