Full Breakdown
Observing the Third Quarter Moon: What to Expect
3/11/2026, 11:38:01 AM
Key Details of the Third Quarter Moon Phase
The third quarter moon phase will occur on March 11, 2024, at 5:39 a.m. EDT (0939 GMT). During this phase, the moon will appear half-lit, with its left side illuminated by sunlight and its right side in shadow. Observers in the United States can expect to see the moon low on the southern horizon, accompanied by the red supergiant star Antares, located approximately 10 degrees to the upper right of the moon.
Observational Highlights
For those interested in lunar observation, the nights surrounding the third quarter phase present an excellent opportunity to view notable features on the moon's surface. The Mare Imbrium, or Sea of Showers, is a significant impact site that spans 700 miles (1,127 kilometers) and will be prominently visible. This area is characterized by ancient lava flows that solidified nearly 4 billion years ago.
Using a telescope, viewers can explore the Montes Apennines mountain range, which forms the southeastern border of Mare Imbrium. The range will be particularly striking as sunlight illuminates its peaks and slopes during the early hours of March 11. As the terminator—the line separating the illuminated and shadowed portions of the moon—moves, features like the Copernicus crater will also become visible, showcasing its shadowed western rim and central peaks.
The Moon's Transition
Following the third quarter phase, the moon will gradually transition from a half-sphere to a waning crescent. This change will culminate in the new moon phase on March 18, when the moon will be obscured by the glare of the sun. Notably, around 10-11 days after each new moon, the Sinus Iridum, or Bar of Rainbows, will exhibit a "Golden Handle" effect, as sunlight catches the upper peaks of the Montes Jura mountain range while leaving the surrounding terrain in shadow.
Official Statements & Responses
Space.com emphasizes the importance of this lunar phase for both amateur astronomers and photography enthusiasts. They encourage readers to explore the moon's changing features and consider investing in quality telescopes and cameras for optimal viewing and photography experiences.
Criticism & Opposition
While the article primarily focuses on the observational aspects of the moon, some critics argue that the accessibility of lunar observation can be limited by urban light pollution, which may hinder the ability to view celestial events clearly.
What's Next
As the moon continues its 27-day orbit around Earth, enthusiasts are encouraged to stay informed about upcoming lunar phases and events. The transition from the third quarter to the new moon will provide additional opportunities for observation and photography.
Verbatim Quotes
- “The half-lit moon is upon us!” — Space.com
