On April 25, 2026, the Moon will occult Regulus, the 21st brightest star, for up to an hour. This celestial blackout offers astronomers a rare chance to probe Regulus, a complex system of at least four stars, 79 light-years away.
21st
Brightest star Regulus
Up to 1 hour
Duration of occultation
79 light-years
Distance to Regulus system
The 2026 Occultation
On April 25, 2026, the Moon will occult Regulus, Leo's brilliant blue-white heart. A glaring 71% illuminated waxing gibbous Moon will dramatically obscure this first-magnitude star, a rare spectacle compared to the Moon's constant occulting of fainter stars.
71%
Moon illumination during occultation
By timing Regulus's disappearance and reappearance, backyard astronomers can help create hyper-detailed 3D maps of the Moon's rugged limb, surpassing the resolution of laser altimetry data from probes like the Lunar Reconnaissance Orbiter (LRO). This makes the 2026 event a rare instance where amateur equipment can produce data of higher precision than dedicated space missions, directly contributing to lunar science.
The full occultation will be visible across the eastern United States, Mexico, the Caribbean, Central America, and northern South America.
The Path of Disappearance: A Guide to Visibility
The visibility zone for the occultation sweeps across the Americas in a broad arc, a result of the Moon’s orbital motion combined with Earth’s rotation. Due to parallax, an observer's specific location determines the exact timing and angle of the event. Think of it as the Moon casting a narrow "occultation path" where Regulus is blocked; if you are outside this path, you will see the Moon miss the star entirely.
This path begins in the southeastern United States and progresses northeastward. Consequently, observers in Florida will see the event begin earlier than those in New York. The occultation will be visible in at least 18 eastern states, including Florida, Georgia, the Carolinas, Virginia, and up through Pennsylvania and New York. The farther north an observer is, the shorter the occultation will be, as the star will be seen to cross a shorter chord of the Moon's disk. For observers, this means that even a move of a few dozen miles north or south can significantly alter the event's timing and duration, making precise location planning essential for serious observation.
18+
Eastern states with visibility
Grazing Occultations: Skimming the Lunar Edge
Along the northern edge of the visibility path lies a razor-thin corridor, only a few miles wide, where a scientifically prized "grazing occultation" occurs. For observers here, Regulus won't simply vanish. Instead, it will skim along the Moon's mountainous northern limb, blinking in and out of view as it passes behind lunar peaks and reappears in deep valleys.
Few miles
Width of grazing occultation corridor
This dramatic blinking provides precise data on the lunar polar profile, a region of intense scientific interest. The 2026 graze path slices directly across densely populated areas of northern New Jersey and the New York metropolitan area, placing millions of potential observers in a prime position to contribute valuable data.
Millions
Potential observers in graze path
Occultation Times and Duration Patterns
The following table shows approximate times for major cities. More importantly, it reveals a clear geographic pattern: the duration of the occultation is longest in the south and steadily decreases as you move north, closer to the graze zone. This change from over an hour in Miami to under 50 minutes in Boston visually demonstrates the geometric effect of parallax on the event. This pattern serves as a practical guide: the farther south your location, the more observation time you'll have for the full occultation.
| City |
Disappearance (Ingress) |
Reappearance (Egress) |
Approx. Duration |
| Miami, FL |
9:16 PM EDT |
10:25 PM EDT |
69 minutes |
| Atlanta, GA |
9:25 PM EDT |
10:21 PM EDT |
56 minutes |
| Washington, D.C. |
9:38 PM EDT |
10:30 PM EDT |
52 minutes |
| Philadelphia, PA |
9:42 PM EDT |
10:33 PM EDT |
51 minutes |
| New York, NY |
9:46 PM EDT |
10:35 PM EDT |
49 minutes |
| Boston, MA |
9:52 PM EDT |
10:38 PM EDT |
46 minutes |
Note: Times are approximate; exact location can shift them by minutes. For pinpoint predictions, consult the International Occultation Timing Association (IOTA) website.
How to Find Regulus Before It Disappears
Finding Regulus is a race against the Moon itself. On April 25, 2026, the star will be positioned just off the Moon's dark limb. The primary challenge for observers will be the intense glare from the 71% illuminated Moon, which can overwhelm the nearby star.
1
Locate the Moon
First, find the Moon in the night sky.
2
Identify the Brightest Star Nearby
Look for the brightest nearby star—that will be Regulus (magnitude +1.35).
3
Confirm with Leo's Sickle
You can confirm the star's identity by locating the "Sickle" of Leo, a backward question mark-shaped asterism for which Regulus serves as the dot at the bottom of the question mark.
4
Use Optical Aid
Using binoculars or a small telescope is highly recommended; they will cut through the lunar glare and make Regulus pop into view, allowing you to watch it right up to the moment it vanishes.
Anatomy of a Disappearance
Dark Limb vs. Bright Limb
Dark Limb (Ingress)
Ingress, the star's disappearance, occurs against the Moon's dark, unilluminated eastern limb. Without lunar glare interfering at the point of contact, Regulus will brilliantly switch off as the Moon's unseen limb passes in front of it.
Bright Limb (Egress)
Egress, the reappearance an hour later, presents a tougher challenge. The star will emerge from behind the Moon's bright, sunlit western limb. The lunar glare makes spotting the star's return a test of patience. For observers, this means you should start watching for reappearance a minute or two before the predicted egress time, as the star can pop back into view suddenly and be easily missed against the bright backdrop.
Sources & References
Scott Wolfe
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