The Great Eruption of Eta Carinae

TL;DR

The paper reevaluates the spectral data of Eta Carinae's 19th-century eruption, suggesting previous claims of inconsistency with theory are based on uncertain measurements and that current models remain plausible.

Contribution

It clarifies that earlier claims of a new physical mechanism are based on misinterpreted and uncertain spectral temperature measurements, reaffirming existing theoretical explanations.

Findings

Previous spectral temperature estimates are uncertain.

No significant contradiction with existing theories.

The eruption's physics remain consistent with prior models.

Abstract

During the years 1838-1858, the very massive star {\eta} Carinae became the prototype supernova impostor: it released nearly as much light as a supernova explosion and shed an impressive amount of mass, but survived as a star.1 Based on a light-echo spectrum of that event, Rest et al.2 conclude that "a new physical mechanism" is required to explain it, because the gas outflow appears cooler than theoretical expectations. Here we note that (1) theory predicted a substantially lower temperature than they quoted, and (2) their inferred observational value is quite uncertain. Therefore, analyses so far do not reveal any significant contradiction between the observed spectrum and most previous discussions of the Great Eruption and its physics.