Search a city, explore historical satellite night lights, and compare four operator-reviewed observing candidates. A darker map is not a clear-sky or access guarantee.
A city search is sent to Open-Meteo’s geocoder. Cloud requests use the confirmed coordinates. No location permission is requested and no search is saved by this tool.
NASA Black Marble · 2016 composite · historical upward light, not live sky brightness or measured Bortle
The map loads only when requested. NASA receives your IP address and requested map area; no GPS permission is requested.
Potter County, Pennsylvania
Wide-field stars, meteor watching and faint targets when the Moon and clouds allow
Use the public viewing area for a short visit. The overnight astronomy field requires registration, a fee and a permit; arrive before dark to park on the field. Red-filtered or shielded lights are required there. Check current conditions before travel.
Official information checked:
Joshua Tree National Park, California
Wide horizons, meteor watching and dark-sky planning
NPS asks stargazers to stay awake within 20 feet (6 m) of their vehicle. No roadside or parking-lot camping. Day-use-only areas close from dusk to dawn. Entrance fees and temporary closures still apply.
Official information checked:
Long Island, New York
Wide-horizon meteors and brighter targets outside central-city glare
A valid 2026 stargazing permit and observing equipment are required. Stay in the designated parking area near your vehicle. The permit expires December 31, 2026; camping and after-sunset tents or portable shelters are prohibited. Environmental closures can override normal access.
Official information checked:
Nerima, Tokyo
Moon, bright planets and learning the sky—not a dark-sky reserve
The operator lists general park access as always open and admission as free, with exceptions for paid facilities. Service-center and facility hours differ. Check current closure notices and do not enter closed sports facilities or protected pond margins.
Official information checked:
1. Search and confirm the country. 2. Load the map and compare the city with the surrounding region at the same zoom. 3. Open an operator-reviewed destination and verify access. 4. Check its actual cloud and Moon forecast before travelling. The first four sites are a maintained starting set, not an automatically generated inventory.
The NASA VIIRS Black Marble layer is the 2016 annual night-light composite. It visualizes light seen from orbit. It does not measure the darkness above your telescope, has no current street-light inventory, and cannot supply a reliable Bortle number for a clicked pixel. Local shielding, terrain, spectrum, weather and the Moon change the view from the ground.
In a bright city, begin with the Moon, bright planets and recognizable constellations. A suburban edge may improve contrast, but direct lamps and haze still matter. A remote destination can improve faint-object contrast only when the target is above the horizon and cloud, Moon, safety and lawful access also cooperate. No class or darkness guarantee is assigned to the listed parks.
Illustrative example—not live data: a darker site with 90% opaque cloud is a poor choice for faint stars compared with an accessible urban site with a clear interval for a bright planet. If the remote site is clear but its parking gate closes before the chosen window, choose another permitted session. Map darkness never overrides a closure.
Bortle classes describe an observer’s sky and are not a direct satellite radiance conversion. We would need a properly licensed, dated sky-brightness model and its uncertainty to offer a numeric estimate. Until then, we show the source, its historical date and the limits instead of manufacturing precision.