PAL

Ptolemaeus Arabus et Latinus

_ (the underscore) is the placeholder for exactly one character.
% (the percent sign) is the placeholder for no, one or more than one character.
%% (two percent signs) is the placeholder for no, one or more than one character, but not for blank space (so that a search ends at word boundaries).

At the beginning and at the end, these placeholders are superfluous.

بعد ما بين (النيّرين)  ‘elongation’

Arabic

References: PH Morelon: I.9:1, 29:4-5
Translation of:
Greek: ἀποχή [PH Heiberg: I.9:1, 82:3]
Modern translations:
French: éloigne<ment> (l'un de l'autre les deux luminaires) [PH Morelon: I.9:1, 28:6]
German: Abstand [PH Nix: I.9:1, 83:4]