The cone’s dark tip — the umbra — still has width when it lands,
so the corridor it draws is solid ink. From inside it the Sun is gone, and the
corona shows.
Not to scale — real gaps are 25× wider.
Annular
penumbraumbraantumbra
The Moon is too far to fill the Sun. The cone closes before the Earth and reopens
as the antumbra, leaving a ring a twenty-first of the Sun’s radius
— thinner than most pictures of it.
Not to scale — real gaps are 25× wider.
Hybrid
penumbraumbra
The tip ends exactly on the Earth’s surface: total where the curve rises to
meet it, annular at the two ends. Under two per cent apart, so the corridor is
drawn as a total’s.
Not to scale — real gaps are 25× wider.
Partial
penumbraumbra
The dark tip misses the Earth entirely; only the penumbra lands. No corridor
— just a wash, drawn as a screen turned down. The median bite takes
0.47 of the Sun’s width.
Not to scale — real gaps are 25× wider.
The catalogue as a grid
A saros repeats an eclipse after 18 years and
11 days, an inex after 29 years less
20. Those are the axes, and reading them forward is how eclipses
are predicted.
Saros series →click a number to pick one
Inex series →click a number to pick one
A saros
223 lunar months: 18 years,
11⅓ days. After that the Moon is back at the same phase, at
much the same distance, and at much the same place relative to the node where its orbit
crosses the Sun’s path — so the eclipse happens again, close enough to look
like the same event returning.
The extra third of a day is what keeps it from being the same event. The Earth turns
another 120° underneath it, so each return lands about a
third of the way further west, and every third return comes back near the same meridian
one step along.
A family opens near one pole as a grazing partial, works its way across the face of the
Earth over twelve to fifteen centuries, and dies as a grazing partial near the other.
Series 126, the column that produces
12 August 2026, opens in 1179
at 72°S and closes in 2459 at
70°N: 72 eclipses, the
31 partials among them all at the two ends.
An inex
358 lunar months: 28 years and
345 days. It is the other step you can take and still land on an
eclipse, and it behaves nothing like a saros. A saros return stays in the same hemisphere;
an inex return crosses to the other one. 12 August 2026
falls at 65°N off Iceland; one cell to the right, same row,
is 24 July 2055 at 33°S
off southern Africa.
Inex families also last far longer. Saros 126 runs
1,280 years end to end. Inex 70 has
members at both edges of the catalogue, 1998 BCE and
2981 CE, and the catalogue runs out before the family does.
The two together are why this is a grid and not a list.
38 inexes less 61 saroses is exactly one
lunar month, so the pair (saros, inex) can name any eclipse, and can name it only one
way.