Lunar Halo

[scarragher]

I wasn't sure what would be the best category to put this question in, but here it is:

I'm looking for the special character that symbolizes a lunar halo. The one I've come across is a semicircle divided by a line (shown here: https://commons.wikimedia.org/wiki/File:Symbol_lunar_halo_WMO.svg). However, on some websites this symbol is cited as representing a lunar corona. Those sites list a different image for lunar halo - the semicircle isn't closed, so the character looks like a pitchfork. I can't find a consensus on which of these images represents the corona and which represents the halo. These links demonstrate my confusion: 

https://books.google.com/books?id=Q7geAQAAIAAJ&pg=PA16&lpg=PA16&dq=character+symbol+for+lunar+halo&source=bl&ots=tSEOaEO-wC&sig=ACfU3U2g4GT68xxrs_tSAOIM3KB80EbOgw&hl=en&sa=X&ved=2ahUKEwj_sMC5ksLlAhUQ2FkKHfD3DwAQ6AEwFXoECAkQAQ#v=onepage&q=character%20symbol%20for%20lunar%20halo&f=false

http://wolstanton.org.uk/code-weather-symbols.php

If anyone can add clarity, or point me to someone who might know, I would really appreciate it!