10304(  1) - 04/02/04 11:29  - [  1]

    PROPOSAL FOR HUBBLE SPACE TELESCOPE OBSERVATIONS   ST ScI Use Only
                                                       ID:      10304
                                                       Version: 1
                                                       Check-in Date: 02-Apr-2004
                                                                      11:29:00

1.Proposal Title:
Departures from Axisymmetry in Planetary Nebulae
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2. Proposal For  3. Cycle  4. Parallel Pointing Tolerance
AR               13        <none>
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5. Investigators
                                                                                     Contact?
    PI: Dr. Matthew Bobrowsky             Computer Sciences Corporation
   CoI: Dr. Noam Soker                    Technion-Israel Institute of Technology       N

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6. Abstract

It is well known that outflows from planetary and proto-planetary nebulae often
exhibit axial symmetry. What is less well known are the *departures* from axial
symmetry, which need to be investigated if we are to have a complete understanding
of how planetary nebulae form and evolve. A study of the departures is very timely,
as 3D hydrodynamic numerical simulations are now being developed. The HST archive
contains ~3000 exposures of >400 different galactic planetary or proto-planetary
nebulae. By measuring the departures from axisymmetry for these targets, we will
learn how the departures are related to, and caused by, the physical and dynamical
conditions of the nebulae and central stars. We will produce a catalog for the
community that includes classifications and comparisons of the departures, and
correlations with physical and dynamical properties. We will apply our results to
departures from axisymmetry observed in PNe and in other types of objects, e.g., SN
1987A, Eta Carinae. We have measured asymmetries for a few sample objects; so we
know we will obtain reliable, quantitative results that we (and others) will use to
understand the origin of the departures from axisymmetry in a variety of objects.
Long after our work on this project ends, the catalog of PN parameters will continue
to benefit the wider community.
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                                                10304(  1) - 04/02/04 11:29  - [  2]

            Summary Form for Proposal  10304

  Item                         Used in this proposal
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  Proposal Category            AR
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