Star Almanack
Eclipses
The Sun, Earth, and Moon line up. A shadow crosses a world.
Why not every month?
A solar eclipse occurs at new Moon, when the Moon passes between Earth and the Sun. A lunar eclipse occurs at full Moon, when the Moon passes through Earth’s shadow.
Most new and full Moons produce no eclipse. The Moon’s orbit is tilted by about 5° to Earth’s orbital plane. Usually the Moon passes above or below the alignment. An eclipse requires the Moon to be near a node, where the two orbital planes cross.
Solar eclipses
In a total solar eclipse, the Moon covers the Sun’s bright face for observers within the path of totality. In an annular eclipse, the Moon appears too small to cover it completely, leaving a ring of sunlight. A partial eclipse covers only part of the Sun. A hybrid eclipse is total along some portions of its path and annular along others.
Lunar eclipses
Earth’s shadow has a pale outer region, the penumbra, and a darker inner region, the umbra. A penumbral eclipse can be subtle. A partial lunar eclipse carries part of the Moon into the umbra; a total lunar eclipse carries the entire Moon inside it. The Moon may remain visible with a reddish appearance during totality.
How to read an eclipse entry
Greatest eclipse is a global reference instant. For a solar eclipse, it is when the Moon’s shadow axis passes closest to Earth’s center; for a lunar eclipse, it is when the Moon passes closest to Earth’s shadow axis. It is not necessarily the time of maximum eclipse at your location.
UTC is the common clock used for the listed times. Convert it to your local time and date. The hour and minute shown below are taken from the source timestamp; seconds are omitted.
Magnitude here describes eclipse geometry, not stellar brightness. Solar magnitude measures coverage along the Sun’s diameter; it is not the fraction of the Sun’s area covered. The lunar values below are umbral magnitudes, measured along the Moon’s diameter. A value above 1 is possible when the Moon lies completely inside the umbra.
Visibility summarizes broad regions. A total solar eclipse is total only inside its narrow path; most people within the wider visibility region see a partial eclipse. A lunar eclipse is visible where the Moon is above the horizon during the relevant phases. These summaries do not supply local contact times or a route map.
2026 eclipses
| Date | Eclipse | Greatest eclipse | Magnitude | Visibility | Observing note |
|---|---|---|---|---|---|
| February 17, 2026 | Annular solar | 12:14 UTC | 0.963 | Partial eclipse from southern Argentina and Chile, southern Africa, and Antarctica; annularity crosses Antarctica. | Use certified solar-eclipse viewers or a properly filtered telescope for the entire event; an annular eclipse never becomes safe to view directly. |
| March 3, 2026 | Total lunar | 11:31 UTC | 1.151 | Visible from eastern Asia, Australia, the Pacific, and the Americas wherever the Moon is above the horizon during the eclipse. | Safe to view directly. Binoculars or a small telescope can enhance the color and structure of Earth's shadow. |
| August 12, 2026 | Total solar | 17:48 UTC | 1.039 | Partial eclipse from northern North America, western Africa, and Europe; totality crosses the Arctic, Greenland, Iceland, and Spain. | Use certified solar-eclipse viewers or a properly filtered telescope during every partial phase. Direct viewing is safe only during the brief total phase for observers actually inside the path of totality. |
| August 28, 2026 | Partial lunar | 04:10 UTC | 0.930 | Visible from the eastern Pacific, the Americas, Europe, and Africa wherever the Moon is above the horizon during the eclipse. | Safe to view directly. Binoculars or a small telescope make the umbral boundary easier to follow across the lunar surface. |
Calculated here, checked independently
The Almanack calculates eclipse geometry from Sun–Earth–Moon positions. Published eclipse catalogues provide independent comparison targets. The visibility descriptions and standard magnitudes in the entries are reference metadata retained against the NASA GSFC catalogue; they are not all independent outputs of the timing calculation.
The 2026 source list is still labeled a first-pass calculation. Its displayed times should not be confused with the separate, more precise solar greatest-eclipse audit.
What the recent check establishes
The recorded October 21, 2026 audit compared the production Besselian solar timing backend with nine frozen NASA reference cases from 1919–2028. Its largest absolute difference was 0.454 seconds, within the test’s 1-second tolerance. That comparison uses matching dynamical timescales: calculated TT against NASA’s published TD labels, whose resolution is one second.
This is evidence for the tested solar greatest-eclipse times. It does not establish the same accuracy for lunar eclipses, local contact times, path boundaries, or every date outside the test set. The timing backend uses cached JPL DE440s source data and an identified Besselian calculation dependency; it does not read the reference catalogue to obtain its answer.
Earth’s rotation: the bowl of Jell-O
Finding the Sun and Moon in space is only part of predicting an eclipse on Earth. Earth’s irregular rotation determines which longitude faces the shadow. The difference between uniform astronomical time and Earth-rotation time, ΔT, matters especially for historical and distant-future visibility. Agreement in a dynamical-time timing test does not remove that uncertainty.
Looking at an eclipse
A lunar eclipse is safe to watch directly, including through binoculars or a telescope.
For direct solar viewing, use eclipse glasses or a handheld solar viewer that meets ISO 12312-2. Ordinary sunglasses are unsuitable. An annular eclipse has no safe unfiltered phase. Only during complete totality, from inside the path of totality, may the fully covered Sun be viewed without a solar viewer; protect your eyes again before any bright part reappears.
Do not use eclipse glasses behind binoculars, a telescope, or a camera lens. These instruments need suitable solar filters secured to their Sun-facing ends. Follow NASA’s eclipse-viewing guidance.