Gloucester Stargazing & Astronomy Report

Key Sky Quality Metrics

SQM (mag/arcsec²)

18.94

Bortle class

Class 7 (Class 7)

Darkness Quotient

32%

Dataset

May 2026

Suburban/urban transition

Gloucester: The Practical Verdict

Gloucester, a small city in Gloucestershire, experiences high light pollution due to its urban and suburban environment. This means that the overall quality of astronomical observation is poor, with much of the night sky obscured by artificial lighting. The most significant limiting factor is the light pollution that plagues the area.

Under these conditions, the Milky Way is not visible at all. Observing focuses need to pivot towards the brightest celestial objects such as the Moon, major planets, bright double stars, and select open clusters. Deep-sky visual observing is largely impractical, while attempts at broadband galaxy photography or Milky Way imagery would likely be unsuccessful.

For those looking to escape this glow, travelling west to Merthyr Cynog presents the best nearby upgrade. Situated about 90 km away, this location offers improved skies closer to a Bortle 4 classification—making it suitable for more serious deep-sky endeavours.

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

Best nearby upgrade

Merthyr Cynog sits about 88 km west and reaches Bortle 4, roughly 8.4x darker.

Moderate dark window

Gloucester's limiting factor is not only light pollution. Around midsummer, Gloucester 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 Gloucester?

No. Gloucester is a Bortle Class 7 sky with SQM 18.94, 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 Gloucester?

Gloucester is Bortle Class 7 (SQM 18.94), a poor urban/suburban sky for astronomy.

Is Gloucester good for stargazing?

Not for serious deep-sky observing. Gloucester 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 Gloucester good for astrophotography?

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

What can you observe from Gloucester?

Primary targets from Gloucester 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 Gloucester?

The closest meaningfully darker mapped site is Rushwick, about 36 km south east of Gloucester, reaching Bortle 5.

When is the sky darkest in Gloucester?

The sky over Gloucester is darkest around January, December. Significant summer limitation: around 63 nights per year have no true astronomical darkness.

Is light pollution in Gloucester getting better or worse?

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

• Rushwick

  Direction

  SE

  Distance (km)

  35.8

  SQM

  20.47

  Bortle

  5

• Ettington CP

  Direction

  NE

  Distance (km)

  53.1

  SQM

  20.39

  Bortle

  5

• Merthyr Cynog

  Direction

  W

  Distance (km)

  88.2

  SQM

  21.25

  Bortle

  4

• Longbridge Deverill

  Direction

  S

  Distance (km)

  77.4

  SQM

  20.93

  Bortle

  4

• Great Bedwyn

  Direction

  SE

  Distance (km)

  70.1

  SQM

  20.70

  Bortle

  5

• Montgomery

  Direction

  NW

  Distance (km)

  98.7

  SQM

  21.16

  Bortle

  4