Assertion: nebula's shell | /r/HasProperty | thin
Facets:
Source sentences:
text: The shells are smooth and thin suggesting they were ejected in as little as five years, but there are streaks of thicker dust detectable within the shells.
text: Optical nebulas of this type are a thin shell on the shock front; the shell is of high density—about 103cm3—and has cooled to a temperature of about 1040K.