A small companion
for a very large sky.

From curiosity to a plan

What time does the sky get properly dark? Will the Moon be in the way of faint stars, or should it become the main event? Could a station cross this part of the sky? Those are practical questions, and this project brings a few of them into one quiet, readable place.

The main tool combines your chosen coordinates, date and time zone with approximate Sun and Moon positions. It highlights the longest interval when the Sun is well below the horizon and the Moon is down, shows how both bodies move through the day, and lets you keep a simple text plan. The optional station tool uses a visibly dated orbital snapshot rather than pretending to be a live feed.

What we try to get right

Useful before impressive. The tools are designed for deciding when to step outside. A chart, a time and a clear limitation should help more than a wall of telemetry.

Explain the uncertainty. A precise-looking number is not necessarily precise in the real world. The methods page names the libraries, thresholds, sources, and conditions these models leave out. The guides distinguish geometry from actual visibility.

Keep the basics close. The calculations run in your browser, with local assets and no account. Coordinate entry is manual. The site does not request access to your device location, camera or microphone.

Write for a real outing. Original field notes cover twilight, Moonwatching and reading a station pass. They link to primary references and emphasize simple equipment, safe locations and flexible plans.

Independent, and deliberately limited

This is an independent educational web project. It is not a space agency, observatory, satellite operator, professional forecasting service or safety system. NASA photography and public orbital data are credited as source material, not presented as partnerships.

The site currently has no advertising scripts, analytics or behavioral tracking. If that changes, the privacy information and any required consent controls need to change with it. We do not claim that a dark interval means a clear night or that a listed satellite will be visible.

Check local weather and site access before setting out. For a time-critical observation, compare with an authoritative current ephemeris. If two tools disagree, check the time zone, horizon convention and data age before trusting the more precise-looking answer.