What a super blue blood moon is and why it is rare
A super blue blood moon is a combination of three distinct lunar conditions that happen to occur together: a supermoon, a blue moon, and a total lunar eclipse that brings a reddish hue to the Moon. The term captures media attention because it is uncommon for all three conditions to align, though each component is well understood in astronomy. In the following sections, the article breaks down each element, explains how these alignments occur, and reviews the most recent instance of a true super blue blood moon to provide an evergreen reference to this popular phrase.
Definition: Understanding supermoon, blue moon, and blood moon
Supermoon
A supermoon occurs when a full or new moon coincides with perigee, the Moon’s closest approach to Earth in its elliptical orbit. This proximity makes the Moon appear slightly larger and brighter than an average full moon, typically by up to about 14 percent and roughly 30 percent more luminous. Supermoons are a regular astronomical pattern tied to the synodic and anomalistic months, and multiple supermoons commonly occur in a year.
Blue moon
A blue moon is a label for the second full moon within a single calendar month in many time zones, a rule popularized in modern usage. Alternatively, the phrase historically referred to an extra full moon in a season that contains four full moons instead of the usual three. The interval between full moons averages about 29.5 days, meaning that blue moons in the monthly sense occur roughly every two to three years, depending on seasonal alignment.
Blood moon
A blood moon is the appearance of a total lunar eclipse, when Earth fully blocks direct sunlight from reaching the Moon. Earth’s atmosphere scatters shorter wavelengths and refracts some sunlight into the shadow, often giving the eclipsed Moon a coppery or reddish tint. The term emphasizes the color observed during mid-eclipse rather than a distinct astronomical mechanism.
How a super blue blood moon forms
For a super blue blood moon to occur, the timing of a full moon must satisfy three conditions simultaneously. The Moon must be at or very near full phase during a total lunar eclipse, placing it within Earth’s umbra. The full moon must also occur close to perigee to qualify as a supermoon. In addition, this full moon must be the second full moon in a calendar month (or the rare extra full moon in a season) to meet the blue moon definition. Because the intervals between lunar phases, perigee, and eclipse seasons do not align perfectly each month, the combination is infrequent, fueling the perception of rarity.
Recent occurrence and details of the last super blue blood moon
The most recent widely recognized super blue blood moon took place in January 2018. That event combined a total lunar eclipse with a supermoon and the second full moon of the month, fitting the common contemporary description. In the table below, the verified attributes of that eclipse are outlined using time phases in Universal Time and related local times for key locations, where available.
| Attribute | Verified Detail | Source Type |
|---|---|---|
| Date and primary visibility | January 31, 2018 (partial before totality, total eclipse approximately 04:51–05:28 UTC) | International eclipse records |
| Supermoon status | Occurred within about one day of perigee | Astronomical ephemeris |
| Blue moon status | Second full moon in January 2018 | Monthly full moon dates |
| Total lunar eclipse | Duration of totality about 76 minutes | NASA eclipse data |
| Regions with clear visibility | North America, parts of Asia, and the Pacific | Visibility maps |
Key facts and common misconceptions
- The Moon does not appear blue during a super blue blood moon; the term blue refers to the calendar naming, not the observed color.
- Supermoons are slightly larger and brighter than average full moons but do not pose any physical risk or unusual phenomena.
- Total lunar eclipses are safe to view with the naked eye and do not require special equipment, unlike solar eclipses.
- The interval between super blue blood moons varies but is commonly cited as roughly 150 to 200 years between occurrences of all three conditions aligning closely; however, patterns of lunar eclipses and supermoons mean the gap is not fixed.
When the next super blue blood moon will occur
Predicting precise dates for a true super blue blood moon requires matching supermoon, blue moon, and total eclipse conditions. The next occurrence after 2018 that fits most definitions is projected to be in 2037, subject to observational circumstances and regional visibility. In the interim, upcoming total lunar eclipses and supermoons will provide opportunities to observe two of the three conditions, with varying degrees of alignment.
How to observe and photograph a super blue blood moon
Observing a super blue blood moon requires no equipment beyond safe viewing practices for lunar eclipses. Photographing the event benefits from using a tripod, a moderate telephoto lens, and exposure settings adjusted for the eclipsed Moon’s brightness; smartphone cameras can also capture usable images when paired with a telescope or telephoto adapter. Checking local moonrise and eclipse timing, as well as weather forecasts, improves the likelihood of clear views. Planning ahead for cold nights and arranging stable viewing locations enhances comfort and image quality.
Eclipse timing by phase and what to expect visually
Penumbral and partial phases
Before and after totality, the Moon moves through Earth’s penumbra and partial umbra, causing subtle shading changes that are often difficult to notice without comparison photographs. These stages can span several hours and may show only a gradual dimming of the lunar surface.
Totality
During totality, the Moon typically deepens to a coppery red or rust color, with brightness levels varying from event to event based on atmospheric conditions. The surrounding stars remain visible, and the eclipsed Moon may appear higher or lower in the sky depending on the observer’s latitude.
Frequently asked questions about super blue blood moons
| Question | Short Answer | Source Type |
|---|---|---|
| Does a super blue blood moon cause natural disasters? | No; there is no verified causal link between lunar eclipses and Earth disasters. | Scientific consensus, geological data |
| Is the term blue moon related to the Moon’s color? | No; it refers to the occurrence of a second full moon in a calendar month. | Astronomical definitions |
| How often do eclipses coincide with supermoons? | Partial or total lunar eclipses occur with supermoons several times per decade, but all three conditions together are much rarer. | Eclipse and lunar cycle statistics |
Summary and practical takeaways
A super blue blood moon is the alignment of a supermoon, blue moon, and total lunar eclipse, each with clear astronomical definitions. While the combined event is infrequent, its components are predictable and well documented. The last widely cited instance was in January 2018, with the next anticipated in 2037, depending on regional conditions. Understanding the mechanics behind the phrase enhances appreciation and supports accurate communication. For observers, planning ahead for visibility, timing, and weather remains the most reliable strategy.
Related topics and further reading
- Supermoon: causes, frequency, and visual impact
- Total lunar eclipse: mechanics, visibility, and safety
- Blue moon definitions and calendar origins