Deep Partial Lunar Eclipse 2026 — A Near-Total Blood Moon

On the night of August 27-28, 2026, Earth's shadow will claim nearly the entire face of the Moon. At maximum eclipse, approximately 90% of the Moon's disk will be immersed in the dark umbra — Earth's deepest shadow. This is not quite a total lunar eclipse, but it is about as close as you can get.

Astronomers classify this as a "deep partial lunar eclipse" — but for observers on the ground, it will look and feel like a total eclipse. The Moon will glow with that characteristic reddish-copper hue, with only a thin sliver of the southern limb remaining in the lighter penumbral shadow.

What Makes This Eclipse Special

Most partial lunar eclipses are underwhelming — the Moon passes through only a fraction of Earth's shadow, looking slightly "smudged" on one edge. But a deep partial eclipse at 90% umbral immersion is a dramatically different experience:

| Eclipse Type | Umbral Coverage | Visual Appearance | |-------------|:---------------:|-------------------| | Shallow Partial | 10–40% | Slight darkening on one limb | | Moderate Partial | 40–70% | Noticeable "bite" out of the Moon | | Deep Partial (this eclipse) | 70–95% | Near-total appearance, strong red color | | Total | 100% | Complete immersion, full blood moon |

This eclipse belongs to Saros series 128, the same family that produced the total lunar eclipse of July 27, 2018 — the longest total lunar eclipse of the 21st century. While this event is technically partial, its depth makes it a worthy successor.

Eclipse Timing (UTC)

| Event | UTC Time | Description | |-------|:--------:|-------------| | Penumbral Eclipse Begins | August 27, 18:04 | Moon enters Earth's outer shadow (penumbra) — subtle dimming begins | | Partial Eclipse Begins | 19:11 | Moon enters Earth's dark inner shadow (umbra) — dark "bite" appears | | Maximum Eclipse | 20:52 | ~90% of Moon in umbra — deepest red-copper color | | Partial Eclipse Ends | 22:33 | Moon exits umbra — dark shadow retreats | | Penumbral Eclipse Ends | 23:40 | Moon fully exits penumbra — eclipse over |

Total duration: 5 hours 36 minutes. Umbral phase: 3 hours 22 minutes.

Local Visibility by Region

| Region | Status | Best Viewing Time | |--------|:------:|-------------------| | East Asia (Tokyo, Beijing, Seoul) | Excellent | Moon high in sky, entire eclipse visible after moonrise | | Southeast Asia (Singapore, Bangkok, Manila) | Excellent | Entire eclipse visible, Moon near zenith at maximum | | Australia (Sydney, Melbourne, Perth) | Excellent | Entire eclipse visible in evening sky | | India (Mumbai, Delhi) | Good | Moon rising with partial phase in progress | | Western Americas (Anchorage, Vancouver) | Limited | Moon setting, partial phase visible at dawn | | Europe/Africa | Not visible | Moon below horizon during eclipse |

Key City Viewing Times

| City | Moonrise (local) | Eclipse Visible? | Maximum Phase (local) | |------|:----------------:|:----------------:|:---------------------:| | Tokyo | 18:28 JST | Full eclipse visible | 05:52 JST (28th) | | Sydney | 17:23 AEST | Full eclipse visible | 07:52 AEST (28th) | | Singapore | 19:05 SGT | Full eclipse visible | 04:52 SGT (28th) | | Mumbai | 19:02 IST | Full eclipse visible | 02:22 IST (28th) | | Honolulu | 19:10 HST (27th) | Full eclipse visible | 10:52 HST (27th) | | Anchorage | 21:40 AKDT (27th) | Partial visible | 12:52 AKDT (28th) |

Use MoonSync to get precise moonrise, moonset, and lunar altitude for your exact location.

Why the Moon Turns Red

The reddish color of an eclipsed Moon — often called a "Blood Moon" — is caused by the same physics that makes sunsets red. As sunlight passes through Earth's atmosphere, short-wavelength blue light is scattered away by air molecules (Rayleigh scattering), while longer-wavelength red light is refracted (bent) into Earth's shadow.

The color intensity varies from eclipse to eclipse, depending on:

1. Atmospheric dust: Volcanic eruptions inject particles into the stratosphere, making eclipses darker and redder. The 1991 Pinatubo eruption made subsequent eclipses nearly black.
2. Cloud cover along Earth's limb: The sunlight that reaches the Moon during an eclipse has passed through Earth's atmosphere at grazing incidence. Cloud cover along the terminator affects brightness.
3. Umbra passage depth: The deeper the Moon passes into the umbra, the darker and redder it appears. With 90% coverage, this eclipse should produce a rich copper-red color on the eclipsed portion.

The Danjon Scale classifies eclipse darkness from L=0 (very dark, nearly invisible) to L=4 (bright copper-red with bluish rim). This deep partial eclipse is expected to display Danjon ~L=3 on the darkened portion — a vivid copper-red that photographs beautifully.

How to Observe the Lunar Eclipse

Unlike solar eclipses, lunar eclipses require no special equipment whatsoever. The eclipsed Moon is dimmer but perfectly safe for naked-eye viewing, binoculars, or telescopes — no filters needed.

Naked-Eye Observation

1. Find an unobstructed view of the sky: The Moon will be fairly high in the southern sky for most Asian and Australian observers.
2. Let your eyes dark-adapt: Turn off lights and phone screens for 10–15 minutes to maximize your night vision.
3. Watch the shadow advance: The umbra moves across the Moon at about 1 km/s — you can visually track its progress minute by minute.
4. Look for color variations: The umbra is rarely uniform. Watch for color bands — the central umbra appears darker, while the edge shows brighter copper tones.

Binocular Observation

With 7×50 or 10×50 binoculars:

• Individual craters become visible as they enter and exit the umbra
• Color gradients across the Moon's surface are more pronounced
• The Moon's dark limb against the starry background is easier to appreciate

Telescope Observation

For telescope users (80mm+ aperture, low magnification ~30-50×):

• Crater timing: Record the exact moment specific craters enter the umbra. These timings have been used for centuries to study lunar orbit variations.
• Star occultations: During the eclipse, the darkened Moon may occult (pass in front of) faint stars — easier to see when the Moon's glare is reduced.
• Surface color imaging: A DSLR or planetary camera on a telescope reveals subtle color variations across the lunar surface — mare (dark plains) appear differently from highland regions when illuminated only by refracted earthlight.

Photography Guide

Lunar eclipses are the most accessible astronomical events to photograph:

| Phase | ISO | Aperture | Shutter Speed | Notes | |-------|:---:|:--------:|:-------------:|-------| | Full Moon (before eclipse) | 100 | f/8 | 1/250s | Moon is bright — standard lunar settings | | Partial Phase (50% covered) | 400 | f/5.6 | 1/60s | Dimmer — adjust as shadow advances | | Maximum Eclipse (90% covered) | 800–1600 | f/4–f/5.6 | 1–2s | Darkest phase — tripod essential | | Exiting Umbra | 400 | f/5.6 | 1/60–1/15s | Brightening rapidly |

Equipment recommendations:

• Lens: 200mm minimum, 300–600mm ideal for frame-filling shots
• Tripod: Essential during deep partial and maximum phases (exposures > 1/15s)
• Remote shutter or 2-second timer: Avoids camera shake
• Shoot RAW: Enables white balance and exposure recovery in post

Using FastTool for Eclipse Planning

MoonSync — Precise Lunar Data

MoonSync provides real-time lunar data for any location, including:

• Moonrise and moonset times — Critical for knowing when the Moon becomes visible after rising
• Lunar altitude and azimuth — Plan your observing location to avoid buildings and trees blocking the view
• Current lunar illumination — Track the eclipse progress as the Moon's apparent illumination changes

Telescope FOV Calculator — Eyepiece Selection

The Telescope FOV Calculator helps plan your telescope setup. A low-magnification eyepiece (40–50×) with a wide apparent field of view (68°–82°) frames the entire eclipsed Moon beautifully, with enough context to show nearby stars.

Track the Eclipse with MoonSync →

The Rarity of Deep Partial Eclipses

While partial lunar eclipses occur roughly twice a year, deep partial eclipses — where more than 80% of the Moon enters the umbra — are far less common. The last comparable event was the November 19, 2021 partial lunar eclipse, which reached 97% coverage — the longest partial lunar eclipse in 580 years.

After August 2026, the next lunar eclipse visible from Asia will be a total lunar eclipse on December 31, 2028 — a New Year's Eve blood moon. But a deep partial with >90% coverage won't occur again until November 2042.

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Eclipse timing data verified against NASA's Five Millennium Canon of Lunar Eclipses and JPL DE440 ephemeris. Umbral immersion percentage calculated from Fred Espenak's eclipse predictions. Saros series data from NASA Eclipse Web Site.