London Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

16.75

Bortle class

Class 9 (Class 9)

Darkness Quotient

14%

Dataset

May 2026

Inner city sky

London: The Practical Verdict

London, the capital city of the United Kingdom, is a global metropolis with extreme light pollution. This significantly affects its sky quality, categorising it as a severe urban environment where astronomical observations are greatly restricted.

From this location, the Milky Way is not visible at all, and stargazers will find that only the brightest astronomical objects, such as the Moon, planets, and double stars, are easily detectable. Narrowband imaging may offer some possibilities, but visual deep-sky observing and meteor-shower watching are largely ineffective.

Nearby sites like Cockley Cley, to the north north east, provide some improvement but are still not dramatically darker. Observers seeking significantly better conditions would need to venture further afield.

At a Glance

Overall

Severe urban sky - This is a severely light-polluted urban sky. Only the Moon, planets, bright stars, and a few specialist targets remain practical.

Milky Way

Not visible - The Milky Way is not visible from this sky.

Best targets from here

Moon, planets, bright stars, double stars, solar system events, narrowband imaging only with care

Do not prioritise

visual deep-sky observing, broadband galaxies, reflection nebulae, widefield Milky Way

Limited nearby upgrade

Cockley Cley is the strongest nearby option but remains Bortle 5; the improvement is real but modest.

Moderate dark window

London's longest dark windows fall in December and January, with the shortest nights around June and July. Plan deep-sky sessions around the autumn and winter months for the best combination of long nights and true astronomical darkness.

Frequently Asked Questions

Can you see the Milky Way from London?

No. London is a Bortle Class 9 sky with SQM 16.75, so the Milky Way is not visible from the city. For Milky Way photography, look for a Bortle 4 or darker site.

What Bortle class is London?

London is Bortle Class 9 (SQM 16.75), a severe urban sky for astronomy.

Is London good for stargazing?

Not for serious deep-sky observing. London is a severe urban sky where the Moon, planets, and a handful of bright targets are the realistic options from the city itself.

Is London good for astrophotography?

Broadband deep-sky imaging is heavily compromised from London and a Bortle 4 or darker site is strongly recommended. Even narrowband imaging is difficult from London without careful processing.

What can you observe from London?

Primary targets from London include Moon, planets, bright stars, double stars, solar system events. Targets such as visual deep-sky observing, broadband galaxies, reflection nebulae are not realistic from this sky.

Where are darker skies near London?

The closest meaningfully darker mapped site is Therfield, about 59 km south south east of London, reaching Bortle 6.

When is the sky darkest in London?

The sky over London is darkest around January, December. Significant summer limitation: around 59 nights per year have no true astronomical darkness.

Is light pollution in London getting better or worse?

Long-term light pollution over London has been broadly stable across the available measurements.

• Horsted Green

  Direction

  S

  Distance (km)

  63.2

  SQM

  20.34

  Bortle

  5

• Therfield

  Direction

  SSE

  Distance (km)

  59.1

  SQM

  19.92

  Bortle

  6

• Frittenden

  Direction

  SE

  Distance (km)

  63.5

  SQM

  19.95

  Bortle

  6

• Althorne

  Direction

  ENE

  Distance (km)

  64.1

  SQM

  19.78

  Bortle

  6

• Flexcombe

  Direction

  SW

  Distance (km)

  75

  SQM

  20.05

  Bortle

  6

• Cockley Cley

  Direction

  NNE

  Distance (km)

  135.2

  SQM

  20.67

  Bortle

  5