Mills Observatory officially reopens for its 91st season

The dome is open, the darker nights are drawing in and Dundee’s Mills Observatory is back for another winter of stargazing.

The observatory officially reopens tonight, beginning its 91st season from its familiar home at the top of Balgay Hill.

Britain’s first purpose-built public observatory has been introducing people to the night sky since 1935, giving generations of Dundonians the chance to look through its telescope and discover a little more about what’s happening above the city.

This year’s reopening follows two particularly memorable seasons for the Mills – its landmark 90th anniversary year and, immediately before that, a record-breaking season for visitor numbers.

Now the lights are off, the telescope is ready and it’s time to start looking upwards again.

Season 91 begins at the Mills

Perched above Dundee in Balgay Park, Mills Observatory has been part of the city for more than nine decades.

What makes the Mills unusual is that it wasn’t built primarily for professional astronomers or scientific research.

From the beginning, it was created for the public.

When it opened in 1935, it became Britain’s first purpose-built public astronomical observatory – somewhere ordinary people could come through the doors, learn about astronomy and see the night sky for themselves.

That remains a big part of its appeal today.

Its distinctive dome houses the observatory’s telescope, which visitors can look through when conditions are suitable, while the building itself offers the chance to learn more about planets, stars and the wider universe.

And on a genuinely clear Dundee night, the view through the telescope can make the trip up Balgay Hill well worth it.

Following two memorable seasons

Season 91 has quite a lot to follow.

More than 14,000 people visited the Mills during its 89th season in 2024/25, setting a new seasonal record and representing a 121% increase in visitors.

Then came the observatory’s 90th anniversary season in 2025/26, marking nine decades since it first opened its doors to the Dundee public.

With the anniversary celebrations now over, the new season starts another year in a story stretching all the way back to 1935.

What could you see this season?

Autumn and winter are when the Mills really comes into its own.

Longer nights mean more time for stargazing, with a changing line-up of planets, meteor showers and other sights appearing over the months ahead.

Among them will be the Pleiades, the distinctive cluster of stars often known as the Seven Sisters.

The Orionid and Leonid meteor showers will make their annual appearances too, while November brings the Beaver Supermoon.

Several planets will also be visible at different stages of the season, including Venus, Jupiter, Mars and Mercury.

There’s one thing the Mills can’t schedule, though: clear skies.

Anyone who spent time trying to stargaze during the observatory’s 90th anniversary season will know that only too well. Cloudy and unsettled weather repeatedly made telescope observations difficult.

A new way to find the best nights for stargazing

That unpredictability has prompted Dundee Culture to try something new for Season 91.

A weekly Mills Observatory Weather Tracker is being published throughout the 2026/27 season, looking ahead to the nights that currently appear to offer the best chance of decent stargazing conditions from Balgay Hill.

Published each Sunday – when the observatory itself is closed – the tracker looks at the forecast for the following week, paying particular attention to cloud cover and the chances of clearer skies during the Mills’ Monday to Saturday opening days.

Each evening is given a simple stargazing outlook, making it easier to spot which nights might be worth considering for a visit.

The forecasts are being published on the Dundee Culture website and shared across its social media channels, with additional updates possible if the outlook changes significantly during the week.

There is, of course, a fairly sizeable Dundee-weather-shaped caveat.

Forecasts change, sometimes quickly, and a promising outlook on Sunday doesn’t guarantee there will be a perfectly clear sky several days later. The tracker also can’t guarantee that telescope observations will take place on any given evening.

Visitors should still check official Mills Observatory information before making the journey.

But for anyone who has made it halfway up Balgay Hill only to discover a thick blanket of cloud overhead, having a better idea of the week ahead certainly won’t hurt.

Planetarium shows are back

Even when the weather isn’t playing along outside, there’s still plenty happening inside the observatory.

The Mills’ popular planetarium shows return for Season 91, taking place on selected Friday evenings between October and March.

Shows begin at 7pm, 8pm and 9pm.

Space is limited, with only 25 places available for each session, and bookings open one month in advance.

Tickets cost £3 for adults and £1.50 for children and can be booked by calling 01382 435967.

When is Mills Observatory open?

During the 2026/27 season, Mills Observatory is open from 4pm until 10pm, Monday to Friday, and 6.30pm until 10pm on Saturdays.

The observatory is closed on Sundays.

Entry to the observatory itself remains free and there is no booking system this time round.

There have been record visitor numbers, anniversary celebrations and now even a weekly attempt to second-guess the Dundee weather.

But the basic appeal of the place hasn’t really changed.

On a clear night, you can climb the hill, step through the doors and look through a telescope at something far beyond the city below.