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We investigate the spectral variability of the Seyfert galaxy Fairall 9 usingalmost 6 years of monitoring with the Rossi X-ray Timing Explorer (RXTE) withan approximate time resolution of 4 days. We discover the existence ofpronounced and sharp dips in the X-ray flux, with a rapid decline of the 2--20keV flux of a factor 2 or more followed by a recovery to pre-dip fluxes after~10 days . These dips skew the flux distribution away from the commonlyobserved log-normal distribution. Dips may result from the eclipse of thecentral X-ray source by broad line region (BLR) clouds, as has recently beenfound in NGC 1365 and Mrk 766. Unlike these other examples, however, the cloudsin Fairall 9 would need to be Compton-thick, and the non-dip state isremarkably free of any absorption features. A particularly intriguingalternative is that the accretion disk is undergoing the same cycle ofdisruption/ejection as seen in the accretion disks of broad line radio galaxies(BLRGs) such as 3C120 but, for some reason, fails to create a relativistic jet.This suggests that a detailed comparison of Fairall 9 and 3C120 with futurehigh-quality data may hold the key to understanding the formation ofrelativistic jets in AGN.

X-ray dips in the Seyfert Galaxy Fairall 9: Compton-thick "comets" or a failed radio galaxy?