Caption: Lunar eclipse types.

Features:

1. Every total lunar eclipse includes a partial lunar eclipse and penumbral lunar eclipse.

   But when we say partial lunar eclipse without further qualification, we usually mean one that does NOT include a total lunar eclipse.

2. Every partial lunar eclipse includes a penumbral lunar eclipse.

   But when we say penumbral lunar eclipse without further qualification, we usually mean one that does NOT include a partial lunar eclipse.

3. Almost all penumbral lunar eclipses (that do NOT go on to being partial lunar eclipses) are partial penumbral lunar eclipse, and thus are usually NOT qualified with the word "partial".

   A penumbral lunar eclipse that is total and does NOT include a partial lunar eclipse is a total penumbral eclipse.

4. The aforementioned "qualifications" are often implied by context only. This is usually true in any jargon.

5. Every eclipse season (duration 31--37 days) must have at least one penumbral lunar eclipse and there can even be two if a full moon occurs just at the start of the eclipse season since the lunar month = 29.530588861 days (J2000) ≅ 29.53059 days (mean J2000 to 7 digits) ≅ 29.5 days is short enough to allow the two full moons during an eclipse season (see Wikipedia: Eclipse season: Details).

   Most often the two lunar eclipses in one eclipse season wiil both be penumbral lunar eclipses. However, it is barely possible that one will a partial lunar eclipse. The eclipse season for a partial lunar eclipse is 24 days around exact nodal alignment (Mo-128): i.e., for about 12 days before and 12 days after exact nodal alignment. So if a partial lunar eclipse happens on day -12, then -12 + 29.5 = 17.5 days which is sometimes within the total range of an eclipse season (duration 31--37 days) which stretches at maximum from -18.5 days before to 18.5 days after exact nodal alignment.

6. See Eclipse keywords below (local link / general link: eclipse_keywords.html):
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