GALAXYHUNTERS · DARKER SKIES, BETTER NIGHTS
Light Pollution Map & Bortle Scale Checker
Check the light pollution and estimated Bortle class for your location. Find darker skies nearby and work out what is worth observing on your next clear night.
You do not need a perfectly dark sky to get started. Knowing what your location is like helps you choose a target, set realistic expectations and decide whether a short trip could make a difference.
YOUR LOCATION · YOUR STARTING POINT
How much light pollution is near me?
Choose a country from the list and enter your ZIP or postal code. The existing GalaxyHunters Bortle Check estimates your local sky brightness and looks for a darker area within 100 km in a straight line.
Sky quality
Bortle Check
How dark is the sky at your location? Enter a ZIP or postal code for a quick estimate, map and practical observing tips.
Milky Way
faint to clearly visible
Suitable targets
- Bright nebulae
- Bright galaxies
- Star clusters
- Milky Way with patience
Tips
- Good transparency matters more than darkness alone.
- Consider the Moon phase and the target’s distance from the Moon.
Darker sky within range
The driving distance may be considerably longer. This is a search area, not a verified observing site. Check access, parking and permission before travelling.
No reliable map data is available for the darker-area search here.
Not in the country list? Use the worldwide location search on our night-sky dashboard. Postal-code coverage and dark-sky map coverage are not the same. The brightness atlas covers roughly 65° south to 75° north; a darker alternative is not guaranteed.
FROM A NUMBER TO A PLACE
How to read a light pollution map
Once your result appears, choose Open light-pollution map to explore the surrounding area on lightpollutionmap.info. That map opens in a new tab; the checker and your result stay here.
- Check the location. A postal code can cover more than one neighbourhood. Zoom in on the place where you actually plan to set up.
- Read the selected layer’s legend. Different layers may show satellite-observed light or modelled sky brightness. Their colours are not interchangeable, and not every colour is a Bortle class.
- Compare a wider area. A small dark-looking patch beside a bright town may still have a light dome on the horizon. Look at the surroundings, not just one pixel.
- Check the night as well as the map. Moonlight, clouds and haze can change what you see without changing the location’s mapped light-pollution estimate.
A map is a useful planning aid, not a live view of the sky. A streetlamp just outside your frame, trees or a bright southern horizon can matter more than the difference between two neighbouring map cells.
THE BORTLE SCALE · 1 IS DARKEST
What does your Bortle class mean?
John E. Bortle’s nine-class scale describes the night sky as an observer experiences it. Class 1 is an exceptionally dark sky; class 9 is a bright inner-city sky. Our map-derived number is an approximation, not a measurement of everything you would see from the ground.
| Class | Typical sky | What to keep in mind |
|---|---|---|
| 1–2 | Exceptionally dark to very dark | A good opportunity for faint galaxies, dark nebulae and wide-field Milky Way views, when the Moon and weather cooperate. |
| 3 | Rural | Many deep-sky targets benefit from the darker background. Check for light domes in the direction of your target. |
| 4 | Rural–suburban transition | A useful compromise for many observers. The Milky Way can be visible under favourable conditions. |
| 5 | Suburban | Bright nebulae and star clusters are worthwhile starting points. Faint structures need more care and often more integration time. |
| 6–7 | Bright suburban to urban transition | Consider bright clusters, the Moon and planets. Emission-nebula imaging may benefit from suitable filters; they are not a cure for every target. |
| 8–9 | City to inner city | Light pollution strongly limits faint deep-sky contrast. Brighter targets can still make a session worthwhile, with appropriate equipment. |
These are starting points, not promises of visibility. Target altitude, transparency, experience and equipment all matter. Photographing an object and seeing it through an eyepiece are different challenges.
A BETTER SKY DOES NOT HAVE TO MEAN A LONG TRIP
Find darker skies near you
The nearby search compares the stored brightness data around your position. It prefers a stable area about two Bortle classes darker and can suggest a smaller improvement when that is the best available option. It searches across country borders within 100 km in a straight line.
What the search checks
Candidate areas must have valid brightness data and fall on mapped land. Several neighbouring cells must also be dark enough, so one isolated dark pixel is not enough. Mapped water and uncertain shoreline cells are excluded as destinations.
What you still need to check
A route link does not mean there is a public observing site or a parking space. Check access, local rules, the horizon and your journey home. The driving distance can be much longer than the straight-line figure.
If no alternative appears, it may mean there is no qualifying darker area nearby, that you are already under a very dark sky, or that the required map data is unavailable. Small islands and narrow coastal strips can be difficult to assess at this resolution.
PUT THE RESULT TO WORK
What can you photograph from a light-polluted location?
A bright sky does not automatically rule out a useful night with a smart telescope or a camera. Start with a target that suits your field of view and rises well above the horizon. Stacking more usable exposures can reveal fainter detail, but it does not remove every gradient or replace a dark sky.
Filters are target-dependent. A suitable narrowband or dual-band filter can help with certain emission nebulae. Galaxies and reflection nebulae emit over a much broader range of wavelengths, so the same filter may throw away light you wanted to collect.
Light pollution and Bortle map questions
Is this a live light pollution map?
No. The checker uses a stored model of sky brightness. It does not detect tonight’s clouds, a neighbour’s floodlight or a temporary event. Use the weather tools and your own view of the sky alongside the result.
Why does my Bortle estimate differ from another map?
Maps can use different source years, models, layers and resolutions. Turning modelled brightness into a Bortle class is also an approximation. Compare the same location and layer, then check how the sky looks from your observing spot.
Does the Moon change my Bortle class?
Moonlight can make faint targets much harder to see or photograph, but it does not change the stored light-pollution estimate shown here. Plan around the Moon’s position and brightness as a separate factor.
Can I photograph galaxies from Bortle 6 or 7?
Yes, some galaxies can be worthwhile photographic targets from a bright location. Expect faint outer structures to be harder to bring out. Target altitude, total usable exposure time and careful background processing matter; a darker site usually gives you a better starting point.
Is a suggested dark area safe and open to the public?
Not necessarily. GalaxyHunters suggests a search area, not a verified observing site. Confirm access, parking, permission and local conditions before travelling. Do not assume a map marker grants permission to enter.
Do I need to create an account?
No account is needed for the checker. Your selected Bortle result is saved in your browser so other GalaxyHunters tools can reuse it. You can update it by checking another location.
Where the estimates come from
The nearby search uses the modelled Light Pollution Atlas 2025 by David Lorenz, based on annual VIIRS night-light data. The local search grid has a resolution of 0.05 degrees. It represents modelled skyglow at the zenith, not a direct measurement of your Bortle class.
The external map is provided by lightpollutionmap.info. Location lookup uses the existing GalaxyHunters geocoding services, including OpenStreetMap contributors. Land and lake boundaries come from Natural Earth.
For the visual observing scale itself, see John E. Bortle’s Bortle Dark-Sky Scale in Sky & Telescope. Local lights, obstructions and changing atmospheric conditions are reasons to treat any map estimate as a guide, not a guarantee.
Back to the Bortle checker ↑Choose a telescope. Plan a night.
New to imaging? Start with the smart telescope guide, explore the Seestar S50 Pro or S30 Pro, then check what you can see tonight for your location.