London Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

17.99

Bortle class

Class 9 (Class 9)

Darkness Quotient

23%

Dataset

May 2026

Inner city sky

London: The Practical Verdict

London, Ontario, a mid-size city in Canada, experiences severe urban sky conditions with significant light pollution. The Milky Way is entirely obscured, limiting stargazing activities to the brightest objects. The primary challenge here is the bright illumination, particularly pronounced toward the east.

In such a challenging observational environment, the Moon, planets, bright stars, and double stars remain your reliable companions. Narrowband imaging can yield results if done carefully, but traditional deep-sky visual observing, especially broadband galaxies and faint nebulae, will be fruitless. Electronic Assisted Astronomy on bright targets offers some potential if you adapt your tools.

While London itself offers limited possibilities, mildly better skies can be found at Brown Brothers (Wrack), Ontario, about 100 km to the east south-east. Though not dramatically darker, it's a tangible progression for those seeking slight relief from urban light.

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

Brown Brothers (Wrack), Ontario is the strongest nearby option but remains Bortle 5; the improvement is real but modest.

Good 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 17.99, 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 17.99), 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 Thames Centre, Ontario, about 20 km east south east of London, reaching Bortle 6.

When is the sky darkest in London?

The sky over London is darkest around January, December.

Is light pollution in London getting better or worse?

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

• Thames Centre, Ontario

  Direction

  ESE

  Distance (km)

  19.7

  SQM

  20.05

  Bortle

  6

• Warwick, Ontario

  Direction

  W

  Distance (km)

  59.8

  SQM

  20.21

  Bortle

  6

• Ratzburg, Ontario

  Direction

  NE

  Distance (km)

  60.1

  SQM

  20.12

  Bortle

  6

• 52, Ontario

  Direction

  E

  Distance (km)

  59.3

  SQM

  19.99

  Bortle

  6

• Brown Brothers (Wrack), Ontario

  Direction

  ESE

  Distance (km)

  102.2

  SQM

  20.58

  Bortle

  5

• Kingsville, Ontario

  Direction

  SW

  Distance (km)

  187.3

  SQM

  20.40

  Bortle

  5