On This Page Sunrise Duration: Quick Facts What Counts as “Sunrise”? The Math Behind Sunrise Duration Twilight vs. Sunrise Extreme Cases: Poles & High Latitudes Viewing & Photography Tips Frequently Asked Questions Sunrise Duration: Quick Facts “How long does sunrise last?” has two honest answers depending on what you mean by sunrise: the strict astronomical … Read more
The Difference Between Dawn and Sunrise. Dawn and sunrise are closely related but not the same thing. Dawn is the gradual brightening of the sky before the Sun appears; sunrise is the specific moment its upper edge reaches the horizon. Feature Dawn Sunrise What is it? A period of morning twilight A specific calculated instant … Read more
What Is a Solstice? The Astronomy Behind Earth’s Longest Days and Nights Twice each year, Earth reaches a point in its orbit where the Sun appears to reach its greatest angular distance north or south of the celestial equator. This event, known as a solstice, is not a matter of weather or calendar convention but … Read more
Watch on YouTube Open Short Open Full What is the Equinox Twice a year, headlines announce that day and night are “equal” everywhere on Earth. It’s a tidy idea — and it’s not quite true. EQUINOX axis perpendicular to sunlight SOLSTICE axis tilted toward / away from sun terminator runs pole-to-pole ☉ sunlight At the … Read more
Sky & Navigation Reference Nautical Twilight: Definition, Times, and Why It Still Matters The twilight window when the horizon and the brightest stars can be visible together — and the reason sailors built a navigation method around it. 0° −6° Civil −12° Nautical −18° Astronomical Quick Answer Nautical twilight is the interval when the sun … Read more
Solar Noon: What It Is and Why It Rarely Matches Clock Noon The exact moment the sun reaches its highest point in the sky — and why that moment almost never lines up with 12:00 on your clock. Table of Contents What Is Solar Noon? Definition and how it differs from clock noon Solar noon … Read more
Why Sunrise Time Changes Every Day Check a sunrise calendar for your city and you’ll notice the time creeps earlier for months, then later — and it never moves by quite the same amount two days in a row. Here’s the actual astronomy behind it. On This Page 1The Short Answer 2An Elliptical Orbit 3Earth’s … Read more