Goodbye, leap second? From 20 May 2027, UTC will run continuously, allowing its offset from Earth’s rotation to grow to an hour. A 2,700-year-old eclipse record from Qufu, China, preserves clues to Earth’s changing day. #LeapSecond #EarthRotation #Astronomy

Where is the Sun taking us? Our solar system circles the Milky Way at about 240 km/s. But Hercules, Cygnus and Crater all describe its direction of motion. The answer depends on what you measure it against. A journey through three reference frames. #Astronomy #SolarSystem

Will Betelgeuse explode? Eventually. But new companion-star evidence offers another explanation for its roughly six-year dimming cycle, not a supernova countdown. A 2-minute tour of what we know and what the sky might look like. #Betelgeuse #Astronomy

If Earth were a basketball, the Moon would be a tennis ball over 7 meters away. Could the other seven planets fit in between? Sometimes. The Moon's distance keeps changing. A short film about the space between Earth and the Moon. 🌍🌙 youtube.com/shorts/4jHuv...

Can Seven Planets Fit Between Earth and the Moon?

YouTube video by 神秘的, 老A (天文通)

youtube.com

The Moon's far side isn't always dark. I made a short flight around the Moon in Stargazing Hub, the astronomy app I'm building. Come watch Earth disappear behind the lunar horizon. 🌙

New: Seasonal trends on Light Pollution Map 🌙 See how sky quality changes across all 12 months, switch between SQM and Bortle, and compare each month with the annual average. Lower-confidence estimates stay visible and are clearly marked. Try it: lightpollutionmap.app

Planning the 2026 Perseids? 🌠 The main maximum arrives Aug 12–13 under a near-new Moon. A few days late can still be worthwhile—especially late night to pre-dawn. This StargazingHub chart uses Borrego Springs as a location-based example. Check your location: stargazinghub.com

A dark map is only the first step. For an actual observing night, I check: • agreement between forecast models • Moon brightness and position • hourly conditions • terrain and the local horizon That is why I built Stargazing Hub. What usually cancels your plans first—clouds, Moon, or local light?

Has your observing site grown brighter—or darker? Our 2025 light-pollution layer is live, based on the complete annual NOAA VIIRS dataset. Compare 2012–2025 for long-term change. 2025 is the latest completed annual layer; 2026 is an estimate. lightpollutionmap.app

🚀 Just launched lightpollutionmap.app! 🗺️ Explore light pollution maps (past, now & 2025) ✨ Find Dark Sky locations 🔭 Check sky visibility & events ☀️🌙 Day/Night map view 🌐 Multilingual support #DarkSkies #Astronomy #LightPollution