The Dusty Environment of the Peculiar Warm Hypergiant HR 5171A

Principal Investigator

Michael Gordon

Proposal ID

07_0053

Category

COOL_STARS

Keywords

• DUST
• EVOLUTION
• MASSIVE STARS
• WINDS/OUTFLOWS/MASS-LOSS

Abstract

HR 5171A is one of a few stars that define the upper luminosity boundary in the HR Diagram for evolved stars. It is a high luminosity warm hypergiant with a peculiar visual and near-infrared lightcurve and a complex, asymmetric nebulosity in the near-infrared which has been attributed to the presence of a low mass companion. The proposed long wavelength imaging with SOFIA/FORCAST will be used to map the spatial distribution and extent of the cold dust to provide a more complete picture of its dusty environment and its mass loss history. We will use FORCAST at a range of wavelengths from 8 to 37 microns to map the spatial extent of the cold dust. We are also proposing spectroscopy to investigate the nature of the grains producing its strong silicate emission features. The proposed imaging and spectroscopy will provide important missing information on the role of dust formation and circumstellar extinction on its peculiar variability.