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Telescopes

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Telescopes

The Department of Physics has three telescopes.

The John Cruickshank Telescope is a 16" telescope system acquired in 2024. It is installed in the new Anne H Cruickshank Observatory, and will be used primarily for research and teaching.

We also have a 10" Meade LX200 formerly housed in the Cromwell Tower Observatory, which has recently been repaired.

Finally, in 2025 we acquired a 4.75" Sky-Watcher Evostar refracting telescope, primarily for outreach.

Our recent acquisitions have followed an expansion of astrophysics-related teaching and research at the 51cg. A new BSc Physics with Astrophysics degree started in September 2024. Existing undergraduate and postgraduate students use astronomical imaging, data, spectroscopy and artificial intelligence (AI) across several disciplines, in their taught courses and final-year projects.

 

Our telescopes

16" John Cruickshank Telescope

The John Cruickshank Telescope on display at an outreach event on 21 October 2024. Image credit: 51cgIn 2024 we acquired a professional level StellaLyra 16"-aperture telescope system to extend and enhance the University’s teaching and research in astrophysics. It is capable of performing high quality deep space with high quality astro-imaging data output. The purchase of this instrument was made possible by the Cruickshank Trust.

The photo to the right shows the telescope set up in the atrium of the Zoology building for an outreach event in October 2024. It is now permanently installed in the Anne H Cruickshank Observatory.

Telescope characteristics:

  • 16" diameter (40.6 cm)
  • 3.25 m ( / 8)
  • reflector design
  • 800x
  • 95% mirrors
  • 0.29" , 200 times sharper than the human eye
  • Virtually zero using strong carbon fibre frame
  • -free optics, as used by , , , and other large professional telescopes
10" Meade LX200

Dr John S. Reid with the 10In the 2000s we acquired a "Classic" 10" telescope (25.4 cm , 2.5 m , /10). This was installed in the Cromwell Tower Observatory (CTO) during its 2000s refurbishment, and at the time was a very popular commercially available instrument.

The image to the right shows Dr John Reid with the 10" telescope under the south dome of the CTO, circa 2000.

In 2023 the 10" telescope was removed from the CTO to prevent its further deterioration, and repaired and restored by BSc student Christopher Willett under the supervision of Dr Charles Wang.

Charles Wang soldering on the new component, right, Christopher Willett disassembling the electronics. Image credit: Charles Wang and Christopher WillettInitial work was on the electronics, which had not worked for at least 10 years, with the optics to follow later. In principle the telescope could still be used manually if the electronics could not be repaired. The problem was identified as a that had resulted from an early manufacturer's modification to the "Classic" LX200 model to make it run on 18V rather than 12V. The image to the left shows the installation of the replacement component.

Restoration of the optics followed next. Most concerning was whether the actual optics had been destroyed by being left exposed to extreme weather cycles in the CTO for up to 20 years with no heating or air conditioning. The telescope tube was disassembled and a grainy deposit carefully cleaned off the (the lens at the entrance to the telescope tube). The images below show the lens before and after cleaning.

LX200 optics before and after cleaning. Image credit: Charles WangWith these repairs done, the telescope was tested first in the Meston Building and later at Sheddocksley Sports Centre playing fields. The kindly loaned two Akit 4000 cameras, and was installed for telescope tracking, for taking photos, and for image editing.

Fraser Mackenzie and Dr Charles Wang standing by the University's 10The tests identified a problem with focus or collimation, which was fixed thanks to some additional help from the AAS. One of the three collimating set screws had come out of its housing and was not moving the secondary mirror at all when adjusted. A final fix to the electronics was required when the motor encoder blew (which had been repaired in the past but not replaced correctly).

The photo to the left shows the restored telescope being used to observe the Sun from the roof of the Fraser Noble Building in June 2025, by placement student Fraser Mackenzie from under the supervision of Dr Charles Wang.

4.75" Sky-Watcher Evostar

In 2025 we acquired a 4.75"-diameter (120 mm) Sky-Watcher Evostar telescope, primarily for outreach and solar observing. This is an with a precision and an .

Technical specifications:

  • 4.75" / 120 mm
  • 1 m ( / 8.333)
  • 40-100x
  • 9x50 optical
  • lens to correct for
  • Potential for solar observing with a / filter
  • Sky-Watcher EQ3-2 GEQ () mount
  • StellaMira 2" 90o to reverse up/down and left/right for easier viewing

Observations with the restored 10" Meade LX200 telescope

Since restoration was completed, the 10" Meade LX200 telescope has been able to take some fantastic images, some of which are shown here.

Copernicus Crater on the Moon

Copernicus Crater on the Moon

The image is enhanced using the Astrosurface programme by taking multiple images of the same object and then digitally "stacking" them together to improve the signal-to-noise ratio. From Westhill, 24/12/2023.

Jupiter and the four Galilean Moons

Jupiter and the four Galilean Moons

After stacking, the image is enhanced by modifying the colour balance, saturation, brightness and contrast to produce a finer image without altering or adding to the original image. From Westhill, 26/12/2023.

Photosphere of the Sun showing sunspots and granulation

Photosphere of the Sun showing sunspots and granulation

A white-light solar filter removes ~99.999% of the sunlight, allowing details like sunspots and granulation to be seen in this unedited image. From the Fraser Noble Building roof around noon on 20/06/2025.

Image credits: Zara Smerdon (BSc link); Brian Stewart, 51cg Photography (JCT); Dr John Reid; Dr Charles Wang and Christopher Willett; Dr Charles Wang; Dr Taylor Coffey (10" telescope); Dr Charles Wang (4.75" telescope); Dr Charles Wang (Copernicus, Jupiter); Fraser Mackenzie and Charles Wang (Sun). 

Source: CS Willett (2024) "A History of Astronomy: From the 17th Century to the Cromwell Tower Observatory, Incorporating Recent Work on the Telescope in Aberdeen", BSc Physics project thesis, 51cg, Chapters 6-7.