The Chrysalis Opens? Photometry from the η Carinae Hubble Space Telescope Treasury Project, 2002-2006* **

摘要: During the past decade η Car has brightened markedly, possibly indicating a change of state. Here we summarize photometry gathered by Hubble Space Telescope (HST) as part HST Treasury Project on this object. Our data include Imaging Spectrograph (STIS) CCD acquisition images, Advanced Camera for Surveys HRC images in four filters, and synthetic flux-calibrated STIS spectra. The HST's spatial resolution allows us to examine central star separate from bright circumstellar ejecta. Its apparent brightness continued increase briskly during 2002-2006, especially after mid-2003 spectroscopic event. If trend continues, will soon become brighter than its ejecta, quite different state that existed only few years ago. One precedent may be rapid observed 1938-1953. We conjecture star's mass-loss rate been decreasing throughout century.