April 11
Abstract:
Eta Carinae (Eta Car) is one of the most studied astronomical objects. It is the
nearest super-massive star to us and contains a massive bipolar nebula that
has been resolved in exquisite detail with HST. In the mid 19th century, Eta Car
mysteriously increased in brightness and became the second brightest star in
the night sky for about 10 years. We now know that during this "Great
Eruption" the star ejected several solar masses of material and formed the bipolar
circumstellar nebula we see today. However, even after so many years of studies, we still do
not understand what triggered this mass-loss episode. In this talk, I will present
our recent discovery of light echoes from Eta Car's Great Eruption. This study
will give us new clues into the physical mechanism of the eruption and it can help
us understand episodic mass-loss events, probably a key ingredient in the
evolution of the most massive stars, and their link to some of the most energetic
core-collapse supernova explosions that are being discovered in extragalactic transient
surveys.