Latest Articles
Why We Always See the Same Side of the Moon Explained
The Moon spins as it orbits Earth, but the two motions are synchronized, keeping nearly the same hemisphere turned our way. Tidal locking explains that pattern; libration lets us glimpse a little beyond its edge.
Read more →How Many Moons Are in the Solar System? A Dated Count
A dated inventory counted 285 known moons orbiting the planets, but the tally changes as new objects are confirmed. Meet the largest moons and see how Earth’s Moon compares.
Read more →Full Moon Names Explained: Wolf, Snow, Worm and Harvest
Many familiar full-moon names reflect seasonal signs, work and local storytelling, but they do not come from one universal naming system. Wolf, Snow, Worm and Harvest Moon show how a name can preserve a useful association without having one certain origin.
Read more →Total, Partial and Penumbral Lunar Eclipses Explained
A lunar eclipse’s appearance depends on how deeply the Moon passes through Earth’s shadow. See what changes in penumbral, partial and total eclipses, and learn what to watch for from the ground.
Read more →When Is the Best Time to See the Moon in the Sky?
The Moon is not only a nighttime sight: its phase determines when it is above the horizon, while its orbit makes moonrise happen later on most successive days. Learn when to look and how to plan around local conditions.
Read more →What Is a Supermoon? Size, Brightness, and Meaning
A supermoon happens when a full moon occurs while the Moon is relatively close to Earth. Its size and brightness do increase, but the change is subtler to the eye than dramatic photographs may suggest.
Read more →Moon Basics
Why We Always See the Same Side of the Moon Explained
The Moon spins as it orbits Earth, but the two motions are synchronized, keeping nearly the same hemisphere turned our way. Tidal locking explains that pattern; libration lets us glimpse a little beyond its edge.
Read more →Moon Phases Explained: A Complete Guide
Everything you need to know about the 8 phases of the Moon — from new moon to full moon and back. The science of the 29.53-day synodic cycle explained.
Read more →Observing the Moon
Lunar Phenomena
Eclipses
Moon Culture & Calendars
Lunar Exploration
Artemis 2: Humanity Returns to the Moon
Launching April 1, 2026, Artemis 2 sends four astronauts around the Moon — the first crewed lunar mission in over 50 years. Here's what it means for the future of lunar time.
Read more →Artemis and the Future of Lunar Timekeeping
NASA's Artemis program is driving the need for precision timekeeping on the Moon. Here's how LTC will enable lunar navigation, communication, and future Moon bases.
Read more →Lunar Time
From Sundials to Lunar Time: A History of Timekeeping
From ancient sundials to atomic clocks to the Moon — how humanity's quest for precise timekeeping led to Coordinated Lunar Time.
Read more →How Lunar Time Is Calculated
The technical details behind lunar time — from the J2000 epoch reference to the Meeus algorithm that calculates moon phases to within 2 minutes accuracy.
Read more →What Is Coordinated Lunar Time (LTC)?
A comprehensive guide to NASA's proposed Coordinated Lunar Time — the future time standard for the Moon and why it matters for space exploration.
Read more →Why Time Moves Faster on the Moon
Einstein's general relativity predicts that weaker gravity means faster clocks. Here's why the Moon gains 56 microseconds every day — and why it matters.
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