8365(  2) - 12/18/98 16:48  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      8365
                                                       Version: 2
                                                       Check-in Date: 18-Dec-1998
                                                                      16:47:26

1.Proposal Title:
Measuring Eta Car's Giant Eruption by Modeling Dust Scattering and Emission in the
Homunculus
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2. Proposal For  3. Cycle
AR               8
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4. Investigators
                                                                                     Contact?
    PI: Barbara Whitney                   Prism Computational Sciences, Inc.
   CoI: Prof. Karen Bjorkman              University of Toledo                          N
   CoI: Prof. Jon Bjorkman                University of Toledo                          N
   CoI: Prof. Adam Frank                  University of Rochester                       N
   CoI: Dr. Michael Wolff                 Space Sciences Institute                      N

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5. Abstract

The goal of this proposal is to determine better estimates of some fundamental
quantities of the Eta Car Homunculus through modeling of HST imagery. These
quantities are: total mass of the emitting gas and dust, and the latitudinal
distribution of dust. The total mass is fundamental because it says something about
the kinetic energy of the eruption which, based on the current estimates, now sits
right up there with the bolometric luminosity of the star. The latitudinal
distribution says something about the nature of the initial mass loss mechanism that
caused the outburst. To get at these quantities, we will need to model the image
morphology confirming the shape of the homunculus and inclination, model the dust
scattering properties, and estimate the dust-to-gas ratio. The wavelength coverage
provided by the WFPC2 camera will nicely constrain dust models as the large
difference in opacities will sample different optical depths. The narrow-band images
will be used in conjunction with imaging models to estimate the gas-to-dust ratio.
We will use accurate 3-D radiation transfer codes and hydrodynamic codes as our
modeling tools.
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  Data Distribution

  Paper Products:  NO
  Media:           ELECTRONIC
  Blocking Factor: 10
  Ship To:         PI_Address
  Ship Via:
  Email:
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                                                8365(  2) - 12/18/98 16:48  - [  2]

            Summary Form for Proposal  8365

  Item                         Used in this proposal
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  Proposal Category            AR
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