Context. The periodicity of 5.5 years for some observational events occurring in η Carinae
manifests itself across a large wavelength range and has been associated with its binary …

The periodic events occurring in η Carinæ have been widely monitored during the last three
5.5-year cycles. The last one recently occurred in January 2009 and more exhaustive …

In late 2006, ground-based photometry of η Car plus the Homunculus showed an
unexpected decrease in its integrated apparent brightness, an apparent reversal of its long …

Abstract Spectra (1951–78) of the central object in η Car, taken by AD Thackeray, reveal
three previously unrecorded epochs of low excitation. Since 1948, at least, these states have …

We have measured the brightness variations in η Carinae for the past 6 years using the
Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph and Advanced …

Aims. Eta Car's ultra-violet, optical, and X-ray light curves and its spectrum suggest a
physical change in its stellar wind over the last decade. It has been proposed that the mass …

Using new and archived ground-based optical and near-infrared photometry (covering more
than three decades) and space-based (HST) narrow-band photometry, we document the …

A comparison of broad-band photometry of the Homunculus (ground-based data) and of
broad-band and narrow-band photometry of the central region (HST-based) from 1997 to …

A full description of the 5.5-yr low excitation events in η Carinae is presented. We show that
they are not as simple and brief as previously thought, but a combination of two components …

ABSTRACT The interacting binary Eta Carinae remains one of the most enigmatic massive
stars in our Galaxy despite over four centuries of observations. In this work, its light curve …