Cambridge Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

19.15

Bortle class

Class 7 (Class 7)

Darkness Quotient

35%

Dataset

August 2026

Suburban/urban transition

Cambridge: The Practical Verdict

Cambridge, a small city in Cambridgeshire, offers generally poor sky conditions for astronomy. With high light pollution, the sky quality here is classified as a Bortle Class 7, making it difficult for any deep-sky observations. The primary limiting factor is the light pollution that generally blankets the area.

The Milky Way is not visible from Cambridge, and sky observers are limited to viewing bright objects such as the Moon, planets, and double stars. Narrowband imaging can sometimes capture bright nebulae, but requires careful processing. More detailed visual observations of deep-sky objects or galaxy photography are largely impossible.

For slightly improved conditions, head to Guilden Morden to the south-west, which provides a measurable reduction in light pollution. It's about 20 km away, offering a modest improvement to a Bortle Class 5 sky but not dramatically darker conditions.

At a Glance

Overall

Poor urban/suburban sky - This is a poor sky for astronomy. The Moon, planets, and a few bright objects remain viable, but deep-sky work is difficult.

Milky Way

Not visible - The Milky Way is not realistically visible from this level of light pollution.

Best targets from here

Moon, planets, bright double stars, bright open clusters, narrowband imaging with careful processing

Do not prioritise

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

Limited nearby upgrade

Guilden Morden is the strongest nearby option but remains Bortle 5; the improvement is real but modest.

Moderate dark window

Cambridge's limiting factor is not only light pollution. Around midsummer, Cambridge loses true astronomical darkness entirely, so deep-sky observing and imaging are strongly seasonal. Plan serious sessions around the darker months.

Frequently Asked Questions

Can you see the Milky Way from Cambridge?

No. Cambridge is a Bortle Class 7 sky with SQM 19.15, 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 Cambridge?

Cambridge is Bortle Class 7 (SQM 19.15), a poor urban/suburban sky for astronomy.

Is Cambridge good for stargazing?

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

Is Cambridge good for astrophotography?

Broadband deep-sky imaging is heavily compromised from Cambridge and a Bortle 4 or darker site is strongly recommended. Narrowband imaging of bright emission nebulae remains viable from Cambridge with appropriate Ha or OIII filters.

What can you observe from Cambridge?

Primary targets from Cambridge include Moon, planets, bright double stars, bright open clusters, narrowband imaging with careful processing. Targets such as visual deep-sky observing, broadband galaxies, reflection nebulae are not realistic from this sky.

Where are darker skies near Cambridge?

The closest meaningfully darker mapped site is Guilden Morden, about 22 km south west of Cambridge, reaching Bortle 5.

When is the sky darkest in Cambridge?

The sky over Cambridge is darkest around January, December. Significant summer limitation: around 66 nights per year have no true astronomical darkness.

Is light pollution in Cambridge getting better or worse?

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

• Guilden Morden

  Direction

  SW

  Distance (km)

  22

  SQM

  20.55

  Bortle

  5

• Manea

  Direction

  ENE

  Distance (km)

  33.3

  SQM

  20.53

  Bortle

  5

• Brent Eleigh

  Direction

  ESE

  Distance (km)

  47.9

  SQM

  20.64

  Bortle

  5

• Little Hormead

  Direction

  S

  Distance (km)

  30

  SQM

  20.17

  Bortle

  6

• Gislingham

  Direction

  ENE

  Distance (km)

  61.1

  SQM

  20.80

  Bortle

  5

• Titchmarsh

  Direction

  WNW

  Distance (km)

  44.5

  SQM

  20.40

  Bortle

  5