Eta Carinae and Its Ejecta, the Homunculus

Gull, Theodore R.

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NASA NTRS · 20140017417

Eta Carinae and Its Ejecta, the Homunculus

Gull, Theodore R.

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Abstract

Eta Carinae (Eta Car), its interacting winds and historical ejecta provide an unique astrophysical laboratory that permits addressing a multitude of questions ranging from stellar evolution, colliding winds, chemical enrichment, nebular excitation to the formation of molecules and dust. Every 5.54 years, Eta Car changes from high excitation to several-months-long low excitation caused by modulation of the massive interacting winds due to a very eccentric binary orbit. The surrounding Homunculus (Figure 1) and Little Homunculus, thrown out in the 1840s Great Eruption and the 1890s Lesser Eruption, respond to the changing flux, providing clues to many physical phenomena of great interest to astrophysicists.

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Gull, Theodore R.. 2014-07-11. Eta Carinae and Its Ejecta, the Homunculus. https://ntrs.nasa.gov/citations/20140017417

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