Hubble Space Telescope Observations of the SN 1987A Triple Ring Nebula

Abstract

We have observed SN 1987A with the optically corrected WFPC2 on the Hubble Space Telescope both in emission lines and in the UV and optical continuum. The previously observed outer nebular structure is shown to be part of two closed unresolved loops. These loops were flash-ionized by the supernova itself. They are not caused by limb brightening of an hourglass shell produced by the interaction of the winds from the progenitor. The inner ring is seen to be extended and may be connected to the new outer rings by sheets of material. However, beyond the outer rings, emission is not seen, implying a very low density (n < 10) for the outer hourglass shell if it exists. The new outer rings are unresolved, and this together with their observed brightness implies a density n > 1000. This density contrast of at least 100 is difficult to reconcile with the conventional picture of the progenitor evolution. Two models for the rings are presented, but each is deficient in important respects. A proper understanding of this system will require new physical insight.

Spatial Distribution and Kinematics of the Molecular Material Associated With Eta Carinae

“…Morris et al (1999) associate it with a torus pre-dating the Great Eruption, that could have been responsible for "pinching" the waist of the Homunculus. Hony et al (2001), on the other hand, argued that it might trace overlapping rings similar to those found in SN 1987a (Burrows et al 1995). The most detailed observations (Smith et al 2002;Chesneau et al 2005) suggest that this dust traces a warm (∼ 300 K) torus highly disrupted by the winds and mass ejections from η Carinae.…”

X-Ray Evolution of SNR 1987a: The Radial Expansion

“…The many spots seen in the optical appear to correspond to the less resolved soft X-ray spots. The X-ray and radio image structures are much simpler than the complex triple-ring structure seen in optical observations (Burrows et al 1995); the X-rays and radio emission are only detected from the central inner ring. This ring appears to be a structure of hot gas that is flattened into a round disk.…”

20 years of Hubble Space Telescope optical modeling using Tiny Tim

“…Using deconvolution to gain back some resolution on the corrected but undersampled WFPC2 camera images, Burrows et al 17 showed that the jet of the young star HH 30 narrows as it is seen closer to the star. In a separate paper, Burrows et al 18 used deconvolution with Tiny Tim PSFs to more clearly reveal the rings around of Supernova 1987a in WFPC2 images (Figure 7). …”