Presentation #227.03 in the session “Stars II”.
We present synthetic photometry of Eta Carinae, obtained with the Hubble Space Telescope’s Imaging Spectrograph (HST/STIS) during the 2020 periastron event. Unlike ground observations, the HST/STIS resolves the star from slow-moving bright material ejected about 120 years ago and it can sample the near UV, the main wavelength range for this star’s luminosity. NUV photometry with the HST goes back more than two decades, including the previous four spectroscopic events. The long-term UV brightening trend has continued, and the temporary decrease in early 2020 followed by recovery through early 2021 closely resembled the 2014.6 event. In the NUV, Eta Car is now more than 2 magnitudes brighter than it was twenty years ago. At visual wavelengths, the rate of brightening has decreased since 2010 while the UV/visual brightness ratio has substantially increased.