Planetary nebulae are a late stage of the evolution of intermediate-mass (~1-8 solar mass) stars. A planetary nebula is formed after an asymptotic giant branch star's ejected mass becomes ionized by the stellar core, which is on its way to becoming a white dwarf. The shaping of planetary nebulae is slowly unveiled through studies of young and evolving nebulae such as NGC 7027. I have conducted an extensive analysis of the first-ever suite of contemporaneous panchromatic Hubble Space Telescope Wide Field Camera 3 (HST/WFC3) images of NGC 7027, extending from near-UV to near-IR. Extinction correction is performed successfully on several HST/WFC3 images, facilitating analysis of the spatial distribution of H recombination and forbidden emission lines within the nebula. The resulting extinction-corrected line ratio images and line ratio diagnostic, as well as an analysis of forbidden emission lines, are used are used to distinguish between photoionization and shock-ionized regions and to place constraints on the gas densities in the shocked regions. This analysis revealed regions dominated by shocks in the NW and SE lobes of NGC 7027. All of these results provide insight on the strength of NGC 7027's outflows, confirming previous assertions that NGC 7027 is among the youngest and most rapidly evolving PNe.

Library of Congress Subject Headings

Planetary nebulae--Observations; Planetary nebulae--Evolution

Publication Date


Document Type


Student Type


Degree Name

Astrophysical Sciences and Technology (MS)


Michael Lam

Advisor/Committee Member

Jason Nordhaus

Advisor/Committee Member

Joel Kastner


RIT – Main Campus

Plan Codes