The Veil Nebula
The complete shell of the supernova remnant contained within the Veil Nebula can not be viewed by the Hubble Space Telescope. For that one needs to use a telescope with a much larger field of view. The image at left is a ground-based observation of the Veil Nebula taken by the Digitized Sky Survey Project. The field of the ground image is roughly 4 degrees square. The position of the Hubble images are marked.
Image Credit: NASA, ESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and the Digitized Sky Survey 2
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