Guides

• How TheDarkestDay Works Out Sunrise, Sunset and the Dark Days — The solar equations, the sunrise definition, and the stated assumptions (a 7:00 am alarm, a 5:30 pm trip home) behind every page.
• Why the Earliest Sunset Comes Before the Shortest Day — In every one of 3,206 US places, the evenings start getting lighter 3 to 25 days before December 21. Here is why, with the numbers for real towns.
• Where in the US the Sun Sets Earliest, and Where the Days Are Shortest — Shortest days, earliest winter sunsets and latest sunrises across 3,206 US places, and why time zones matter as much as latitude.
• What Falling Back Does to Your Sunset, Town by Town — The November clock change moves sunset an hour earlier overnight. How many US places end up with sunset before 5 pm, and how long until it comes back.
• Sunrise Alarm Clock or Light Therapy Lamp: What the Daylight Numbers Say — Across 3,206 US places, how many have a real daylight case for a sunrise alarm clock, a light lamp, both, or neither. Not medical advice.
• Embed a Shortest-Day Daylight Badge for Your Town — A free badge with any of the 3,206 places' shortest-day daylight and sunset, one iframe, no sign-up, credited back to TheDarkestDay.