Starship Asterisk*

I see that Simbad agrees with your identification of Gum 56 with the Prawn nebula (IC 4628). But a quick google finds that many other sites say that Gum 56 is the catalog number for *the* Gum nebula, the close, big one that includes the Vela supernova remnant. This includes the Wikipedia article on the Gum Nebula and several other astronomy sites.

So which is it? Gum's original paper is not available through the ADS for an immediate check.

Unfortunately, I've noticed that Simbad is not always reliable when it comes to nebula identification.

Just for the record, the Wikipedia was wrong about the Gum Nebula. The Gum Nebula is Gum 12 in Gum's famous catalog. Gum 56 is the Prawn Nebula - so APOD is correct.

I will see if I can get the Wikipedia article corrected.

I've fixed the Wikipedia article. You can see the full list of Gum nebulae at my Galaxy Map site.