courses

Tackle that seemingly endless selection of course offerings; a roundup of helpful resources and sound advice for selecting the best courses and acing them.

What Causes Halos Around the Moon and Sun? The Science Behind Solar and Lunar Halos
Understanding Halos: A Simple Overview A halo around the Sun or Moon is a ring of light that forms when light passes through ice crystals in high-altitude clouds.
By shahkar jalalabout a month ago in Education
How Ancient Calendars Were Based on Astronomy: The Science of Timekeeping in Early Civilizations
The Sky as Humanity’s First Timekeeper Before writing systems were fully developed, early humans noticed patterns in nature:
By shahkar jalalabout a month ago in Education
Why the Moon Has Phases: The Science Behind Lunar Cycles and Changing Moonlight
The Moon Does Not Change Shape One of the most common misunderstandings is that the Moon physically changes shape. It does not.
By shahkar jalalabout a month ago in Education
Teaching English to Police Officers
Monday - bored Tuesday - bored Wednesday - taught English to the police Thursday - bored Friday - bored but productive Saturday - collected stamps
By Max Brooksabout a month ago in Education
What Makes Some Stars Visible to the Naked Eye
Understanding Star Visibility Not every star in the sky is equally visible. A star’s visibility depends on its apparent magnitude, which is a measure of how bright it appears from Earth. Apparent magnitude is influenced by two main factors:
By shahkar jalalabout a month ago in Education
How Astronomers Measure the Brightness of Stars
In this detailed guide, we explore how astronomers measure stellar brightness, the tools they use, the scales involved, and why these measurements are essential for understanding the universe
By shahkar jalalabout a month ago in Education
Why the Southern and Northern Skies Look Different
Earth’s Curvature Changes Your View of the Sky The most important reason the skies differ is simple: Earth is spherical.
By shahkar jalalabout a month ago in Education
How Earth’s Rotation Affects Star Positions
Earth’s Rotation: The Fundamental Cause The key to understanding star motion lies in one simple fact: Earth rotates from west to east.
By shahkar jalalabout a month ago in Education
Why Constellations Change Over Thousands of Years
The Myth of “Fixed” Stars For much of human history, stars were called “fixed stars” to distinguish them from wandering planets. Unlike planets, stars seemed locked into permanent patterns.
By shahkar jalalabout a month ago in Education
The Science Behind Eclipses and Their Rarity
What Is an Eclipse? An eclipse occurs when one celestial body moves into the shadow of another. In our Earth–Moon–Sun system, eclipses happen when these three objects align in a nearly straight line.
By shahkar jalalabout a month ago in Education
Why the Moon Appears Larger Near the Horizon
Is the Moon Really Bigger Near the Horizon? The short answer is no. The Moon’s physical size does not change during the night. In fact, when the Moon is near the horizon, it is actually slightly farther away from you than when it is overhead. That’s because when it’s overhead, you are about one Earth radius (roughly 6,371 kilometers) closer to it than when it’s on the horizon.
By shahkar jalalabout a month ago in Education
How to Read the Night Sky Without a Telescope
Why You Don’t Need a Telescope Many beginners assume astronomy requires powerful equipment. In reality, some of the most beautiful celestial sights are visible without magnification.
By shahkar jalalabout a month ago in Education