# Stingray Nebula

An entry in Fortnightly Topic Challenge #35: Restricted Title 1. Inspired by the title of this xkcd comic, but in no way related or affiliated beyond the shared name.

This is the stingray nebula:

Spectacular, isn't it?

This is a nebula map of another part of the sky:

Unfortunately, it only contains data from a limited spectrum of light, so whilst you can see the stars, you can't see the nebulae themselves. I need your help restoring it...

Luckily, as with all nebula maps, it follow the standard rules, which - as I'm sure you'll recall - consist of:

1. Every square of the map belongs to exactly one nebula
2. Each nebula consists of a single set of contiguous squares connected by edges
3. All nebulae have at least one axis of reflective symmetry
4. The letter in each star is a relative magnitude indicating the number of squares in the containing nebula:
• $A$ is strictly less than $B$, which is strictly less than $C$, and so on...
• In this map, $A = 1$ and $L = 20$
5. Stars are considered to be part of a nebula, thus cannot be shared and must be taken into account when applying rule 3

Complete the nebula map by indicating which squares of the grid are contained within each nebula.

• Is a nebula necessarily connected? – Riley May 29 '18 at 2:29
• @Riley - yes, all squares within a given nebula are contiguous (on edges, so no diagonals). – Alconja May 29 '18 at 2:42
• Must the shown letters be symmetric within the nebulae? For example, is a straight horizontal line with five squares connecting the Es in the top left corner allowed? – Austin Weaver May 29 '18 at 3:12
• @AustinWeaver - that would still be symmetrical anyway (vertically mirrored), but yes, stars are part of the nebula, so rule 3 still applies. – Alconja May 29 '18 at 3:27
• Lovely puzzle. Saw Alconja, was not disappointed. – BmyGuest Jun 8 '18 at 8:24