United States · Urban Night Sky Place
Stargazing at Observatory Park at Turner Farm
How dark this certified sky really is, how far it is from the nearest cities, a live seven-night forecast for the site itself, and the moon-free nights worth planning around. Official DarkSky International page ↗
How dark the sky really is at Observatory Park at Turner Farm
Modelled zenith brightness at the site's coordinates is 18.79 mag/arcsec², which maps to roughly Bortle 7 (what each level means). This is an approximation from the 2024 light-pollution atlas, not a field measurement — and it describes the single point DarkSky lists, not the darkest corner of the urban night sky place.
At an estimated Bortle 7 this is an urban sky. Urban Night Sky Place status here is about protecting what night there is inside the city — expect the Moon, planets and the brightest stars, not the Milky Way. If you want a dark sky, use the nearest-cities list below in reverse: this place is where city dwellers start, not where they end up.
Getting to Observatory Park at Turner Farm
The nearest cities we publish guides for, with the direction to head and a rough drive estimate.
- From Washington
head west · 25.3 km straight-line · ≈32.9 km by road · ≈36 min · reachable tonight
- From Philadelphia
head south-west · 212.3 km straight-line · ≈276 km by road · ≈3.4 h · weekend trip
- From New York
head south-west · 340.2 km straight-line · ≈442.3 km by road · ≈5.1 h · weekend trip
Estimated from straight-line distance x a 1.3 road-detour factor and staged average speeds (40 km/h leaving town, 70 km/h regional, 95 km/h highway). It is a rough guide, not a routed drive time.
The next seven nights at Observatory Park at Turner Farm
Loading the live forecast…
Plan the next 90 days at Observatory Park at Turner Farm
Moon-free dark windows are astronomy — computable years ahead. Cloud is not: beyond the 16-night forecast nobody knows the weather, and we won't pretend to. What five years of reanalysis can say is how often each month's nights actually stayed clear here.
- Nov 2–1514 moon-free nights59% of November nights here stayed clear (2021–2025)
- Dec 2–1413 moon-free nights47% of December nights here stayed clear (2021–2025)
- Dec 31 – Jan 1314 moon-free nights47% of December nights here stayed clear (2021–2025)
Clear nights by month, 2021–2025
- Jan47%
- Feb48%
- Mar56%
- Apr58%
- May53%
- Jun63%
- Jul69%
- Aug65%
- Sep59%
- Oct70%
- Nov59%
- Dec47%
Clearest months historically: October (70%), July (69%), August (65%); across the year 58% of nights with astronomical darkness stayed clear.
"Clear" = weighted cloud cover (low 0.5 / mid 0.3 / high 0.2) ≤ 20% across the night's astronomical darkness. ERA5 reanalysis via Open-Meteo Archive, 2021–2025 (CC BY 4.0) — historical frequency, not a forecast. Once a window comes within 16 nights, the live forecast above takes over.
Put Observatory Park at Turner Farm's dark-sky nights on your calendar
Every month has a stretch of nights when the Moon leaves the dark hours at Observatory Park at Turner Farm essentially moon-free. Subscribe once and each window lands in your own calendar, about a year ahead — no account, no email.
moon & darkness geometry only — cloud can't be known this far out; check the live forecast above when a window gets close
Questions people ask about Observatory Park at Turner Farm
- How dark is the sky at Observatory Park at Turner Farm?
- Modelled zenith brightness from the 2024 World Atlas of Artificial Night Sky Brightness puts Observatory Park at Turner Farm at about 18.79 mag/arcsec², roughly Bortle class 7. That is an approximation derived from satellite data, not a field measurement; it is certified by DarkSky International as an Urban Night Sky Place.
- How far is Observatory Park at Turner Farm from Washington?
- About 25.3 km in a straight line, heading west from Washington. Using a 1.3 road-detour factor and staged average speeds that is roughly 32.9 km and 36 min of driving — an estimate, not a routed drive time.
- When is the next moon-free dark window at Observatory Park at Turner Farm?
- The next stretch of essentially moon-free dark hours runs Nov 2–15 (14 nights), computed from Moon phase and altitude with Skyfield and JPL DE440s. Cloud cannot be known that far ahead; the live seven-night forecast on this page shows real cloud cover once a window is close.
- What is the clearest month at Observatory Park at Turner Farm?
- Over 2021–2025, October (70%), July (69%), August (65%) had the highest share of nights with astronomical darkness that stayed clear (weighted cloud cover ≤ 20%); across the year it was 58%. ERA5 reanalysis via Open-Meteo — historical frequency, not a forecast.
Place name and coordinates: DarkSky International (reviewed 2026-07-15, data 2026-10-13). Light pollution: David Lorenz, World Atlas 2024 (EOG VIIRS, CC BY 4.0), approximate. Cloud: Open-Meteo.com (CC BY 4.0). Moon and darkness geometry: Skyfield + JPL DE440s, computed locally. Drive times are estimates, not routes.