| Modulo | Universe

Cosmology, Astronomy and Abstract Mathematics

Leave a comment

Next Abriachan Astronomy Dates

I’m excited to be hosting two more astronomy events alongside the Abriachan forest team in March and April 2018.  Details and ticket links below.

Star Cluster Special – March 10th (moved from Feb 10th) 7pm-9pm


The Hyades and Pleiades Star clusters

Explore the great winter open clusters under moonless dark skies with campfire stories to follow. Outdoor binocular guiding under clear skies. Indoor talk, astronomy activities and virtual guiding in the classroom in the event of poor weather. Refreshments provided.

Ticket link: https://www.eventbrite.co.uk/e/dark-sky-observingwith-a-sta…

Solar Special and the Life of Stars – April 14th 2pm – 4pm


A typical G-type main sequence star – locals have dubbed this one ‘The Sun’

A Sun special exploring our nearest star and the life of giant stars. Outdoor sun projections and activities, with illustrated talk and refreshments. Suzann even has plans for a solar pizza oven!

Ticket link: https://www.eventbrite.co.uk/e/some-sunny-science-and-the-l…

All stargazing events organised in collaboration with the Abriachan team, astronomer Stephen Mackintosh and learning coordinator Suzann Barr. Campfire tales delivered by forest ranger Clelland.

For group bookings please email: abriachanforest@gmail.com

Leave a comment

Mesolithic Stargazing at Abriachan


Stargazing at Abriachan – Photo by Ken Armstrong – Castlehill Photography

A fantastic night of stargazing was had at Abriachan community forest last Friday.  The night was dubbed ‘Mesolithic Stargazing’ and was delivered as part of the Highland Archaeology Festival.

Abriachan is an excellent location for dark sky observing, being both well elevated in the high moors above the Great Glen and miles away from urban light pollution.  Its southern skies are particularly stunning.

Interest in the event far exceeded expectations, with a Facebook event erected in August achieving a shared reach of over 35,000 people!  The Sky at Night magazine even got in touch, wishing to highlight the event in the ‘What’s On’ section of the print magazine.   Because of this, a late request for email bookings had to be enforced by Abriachan to control numbers.  This left lots of folks disappointed but ultimately ensured the event ran smoothly.

There were two elements to the evening which people could move between – stargazing and mesolithic campfire stories.  I was set up to host the stargazing component out in the open above the forest classroom, while ranger Clelland built a hearty fire in the woods for camp fire tales.  Meanwhile, Suzann and the Abriachan team prepared the site and classroom, marking out paths with glow-sticks to help people negotiate safely in the dark.  They also readied hot drinks, soup and snacks to serve from the Camanachd Cabin beside the classroom.


Mesmerising colours – Photo by Ken Armstrong – Castlehill Photography

Around 7pm folks started arriving, just as an ominous bank of clouds rolled in.  I needed some extra time to decide if the stargazing would go ahead at this point, so Suzann helpfully escorted the first group of folks down to the campfire for stories.  Meanwhile, lots more people were arriving and a call had to be made soon on whether to abandon the stargazing, and instead present an indoor talk I’d prepared on ‘Ancient Astronomy’.

Thankfully the shifting skies soon made that decision easy.  The clouds began melting away revealing a lovely evening sky peppered with brighter stars.  By the time I escorted my first group to the appointed observing spot the skies were ablaze with stars, and a beautiful Milky Way soared overhead.  After that, conditions got better and better, and to top it all off a mesmerising display of northern lights materialised, distracting everyone from the stargazing as it ebbed and rippled high in the northern sky.


The Summer Triangle and the Cygnus Rift, captured by photographer Claire Rehr

In rough order, the stargazing tour covered the following:

  • Ursa Major and the Big Dipper asterism
  • Ancient navigation and time keeping using Polaris and circumpolar constellations
  • Properties of Polaris
  • Cassiopeia – the 1572 Tyco Brahe supernova
  • Perseus – the Merfak group, the double cluster and the ghoul star Algol
  • Andromeda – the stunning M31 galaxy.
  • The story of Perseus, Andromeda, Pegasus and the sea monster Cetus
  • The summer triangle – Vega, Deneb and Altair
  • Cygnus – the galactic disk, the Cygnus rift and the Kepler exoplanet survey
  • Lyra – Vega and the double double
  • The unique properties of the blue-white giant Vega
  • Delphinus and Sagitta – the coat hanger asterism
  • Meteor storms and large impactors

The tour was largely naked eye and with binoculars.  I had hoped to get some telescope time in with the 200mm auto tracker, but the groups were too large to make that a practical option.  However, some folks who stayed behind after the tours did see some pleasing views of Andromeda and the double cluster in the eyepiece.


More stunning aurora, captured by photographer Claire Rehr

Overall the evening was a big success with lots of positive feedback.  The addition of a stunning display of northern lights made the experience all the more memorable.  By all accounts the story telling was very well received too, with Clelland recounting a Celtic tale about Ursa Major, including the ghoul star ‘Algol’ in Perseus, which we’d surveyed earlier in the sky tour.

A followup event is planned for November 18th.  Please check the Facebook site for details.


Leave a comment

Globular Cluster M3

Globular clusters are some of the best deep space objects to view with a video telescope setup.  These tightly bound swarms of stars orbit our Milky Way at a distance of 100,000 lights years or more and contain many more older stars than open clusters.  The density near the core of these stellar globules is very pronounced indeed, such that any inhabitants of a planet deep inside one would see a night sky peppered with incredibly bright stellar neighbours.  This artist impression from William Harris and Jeremy Webb illustrates the point beautifully.

glob inside

What the sky might look like inside globular cluster ’47 Tucana’ where nearly 600 thousand stars jostle within a volume of space only 120 light years across.

I planned to video the famous M3 globular tonight after seeing its relative high altitude and fortuitous position in SkySafari, and noting with some relief how clear and enticing the moonless sky looked.

After very little effort, and with a short 3 second integration time, I was able to watch this spectacular sight slowly materialise in the video monitor


M3 contains over 500 thousand suns at a distance of 34 thousand light years from earth.

This image is incredibly bright and vibrant compared to naked eye views of M3 and is only slightly marred by a few visual artefacts due to the sensor technology.  The bloated white dots at the widest periphery of the image are not stars but hot spots due to the video chip heating up during long exposures.  Despite this I’m sure you’ll agree the view is a triumph of video observing, readily revealing the awesome density and structure of the cluster.

There are over 150 of these satellite clusters orbiting our Milky Way galaxy and their formation is the topic of excited debate.  The fact they harbour such a high proportion of older stars suggests they were some of the first stars to evolve within the overall galactic neighbourhood.

As far as the question of technological life existing within these systems, the chaos from closely interacting stars (on average only 1 light year apart) might prove an unfavourable environment.  Stars and planets in such a system would be under constant perturbation from nearby neighbours imparting gravitation ‘tugs’, resulting in unstable planetary orbits.

Leave a comment

Merkinch Astronomy Evening

I was delighted to be approached by Caroline Snow, who manages the local Merkinch Nature Reserve, to host an astronomy evening in March.  Our mutual friend Russel Deacon introduced us via Facebook and after some informal chat we agreed enough of an initial proposal for Caroline to begin promoting the event on social media and some local papers.

From a dark sky perspective the area isn’t perfect as there’s a fair bit of light pollution facing south and east back towards Inverness.  But it’s a beautiful location overall with lovely clear views north and west and perfectly acceptable dark skies in those directions.  It was also a good compromise between darkness and accessibility for the people we hoped to attract from the local area and beyond.

We initially planned the tour for Friday 24th of March but the weather was a bit patchy and looking better the following day.  So after some further discussion Caroline and I decided to go for for the clearest night possible, and delayed the event until Saturday.

The next day was sunny and clear as forecast and when twilight fell I headed over to the reserve to setup an hour or so early.  This was the lovely scene as the sun set over the observing site.


Sunset at Merkinch Nature Reserve looking North West.

My first challenge arose when unloading the telescope beside the picnic benches at our chosen spot. I realised I had some company next to me in the form of a few local teenagers who were blaring out Johnny Cash and Elvis from a brightly flashing ghetto blaster!  I approached them to say hello and explain what I was doing here, and in return was offered a swig from a Buckfast bottle!  After declining and explaining I had my van with me, one of the party lurched towards me and gave me a giant bear hug, which was a lovely welcoming gesture but threatened to unbalance me and the large bag of astronomical equipment I was carrying!  Dusting myself down, I thanked them and invited them to join the tour when it got underway.  I then continued with my astronomical setup, calmed by the soothing melodies of ‘Love Me Tender’ drifting through the darkness.


Elvis performing in front of a large comet.

The plan for the evening was a naked eye and binocular constellation tour, focusing on some interesting targets I’d prepared to discuss in advance.  The telescope would serve to give more detailed views of a few select objects we’d be looking at.  At this stage I was only expecting perhaps a dozen people to turn up but I severely underestimated Caroline’s promotional skills; over the course of the evening about 30-40 people appeared.  This was obviously fantastic but meant individual telescope time was going to be limited.

As the tour started the next challenge arose.  Both laser pointers we’d taken down with us failed, producing a pitiful beam only I could see.  An audience member came to the rescue and offered me his laser pointer, but incredibly that failed too!  The result was that only a few of the more experienced stargazers really knew what I was pointing at.  The only real way out of this pinch was to use the telescope to track to each object in turn and invite people over to the eyepiece.  This let everyone know the rough direction I was pointing at and afforded them a great view of each target.  Phew!

Eventually the pens warmed up and the party really kicked off when people started asking questions – really interesting ones.  What were supernova?  How large is the universe?  Why are stars different colours?  Where does the plane of the milky way sit?  The list was impressive and resulted to some great crowd chat and one to one conversations.  Some of the best questions came from the younger members of the audience, some of whom were so small they had to be lifted up to the eyepiece to see through the telescope (note to self:  bring a step next time).

In rough order our stellar tour took us through the following:

  • The Plough (Mizar/Alcor double, Alkaid) 
  • Plaeides cluster 
  • Aldebaran (the follower)
  • Hyades cluster
  • Orion (Rigel, Betelgeuse and the great Orion nebulae)
  • Double Cluster in Perseus
  • Beehive Cluster
  • Auriga (M37 and Capella)
  • M3 Globular
Simon Garrod

Simon Garrod took this nice image of Orion from our observing position at the Merkinch Nature Reserve.

Highlights?  The Orion nebulae and the M3 globular cluster were real crowd pleasers in the scope.  M3 looked great in the eyepiece despite being in the light polluted eastern sky, its densely speckled core in clear evidence.


The M3 globular cluster is a fantastic target even with moderate light pollution.

After an hour or so people began to filter off home but the stragglers were rewarded with Jupiter just beginning to rise in the East.  Despite a view impinged by a tree the telescope did a great job of bringing Jupiter and its moons in for some closeup action.  There was general gratitude and thanks all round, leaving Caroline and myself thoroughly rewarded by a successful night.

If you’d like more information on the Merkinch Nature Reserve and all the events Caroline’s coordinating visit their Facebook page at Friends of Merkinch Local Nature Reserve and look out for another astronomy evening later this year.

Leave a comment

Galaxy NGC 2903

Why this galaxy on this particular night?  Simply because it was a relatively bright object that was high in the sky within Leo and facing south, the direction of least obstruction from my local observing position.  One of the best tips I learned about observing deep sky objects, in particular galaxies, is to never underestimate the benefits of superior elevation.

Setting up my video telescope at its maximum integration time of 10 seconds, I wasn’t holding too much hope of anything spectacular appearing from these semi light polluted skies.  I was thankfully mistaken.


Despite its staggering distance of nearly 30 million light years, the video screen began resolving a beautifully presented barred spiral galaxy with easily discernible spiral pathways, surrounding a very bright core.  I’m always in awe when viewing distant galaxies like this in real time.  The main idea that captures my imagination is the understanding of what makes up those dim dust lanes – billions of suns!

NGC 2903 is only slightly smaller than our own Milky Way at over 80,000 light years across and is very similar in structure to our own island universe.  Its central bar is a common feature in spiral galaxies found in around two thirds of them.  The formation of these bar structures is still poorly understood.  The most popular hypothesis is due to a density wave propagating from the galactic core, reshaping surrounding dust into a long column.  In general these structures indicate relative maturity for a galaxy – younger galactic siblings don’t have them.

Leave a comment

The Whirlpool Galaxy (M51)

They say good things come to those who wait.  Never  was this more exemplified than this evening after several hours in bitterly cold conditions on Culloden moor with my video telescope.  The cold made setup and targeting much more fraught than usual, and the small gas stove I’d balanced pecariously beside the monitor did little to help.

However, near the end of my session I hit the jackpot when this stunning image of the Whirlpool galaxy, over 23 million light years away,  materialised from the video screen.

Whirlpool galaxy

This image is a true testament to the power of video astronomy and the huge increase in aperture it lends to amature telescopes.  Dust lanes and connective spiral arms are clearly in evidence here.  The best naked eye views of the Whirlpool I’ve seen have only really resolved the two central cores of the interacting galaxies.  You generally need a scope of 16 inches or more to reveal dust tendrils in this much detail.

This is how the Earl of Rosse sketched the galaxy back in 1845 with his monstrous 72 inch dobsonian from the grounds of Birr Castle in Ireland.


Of course back then these structures were given the loose classification of ‘nebulae’ and were assumed part of our local galaxy.  It wasn’t until the 1920s when Edwin Hubble observed cepheid variable stars within each bright core of the Whirlpool that this image was understood to be two distinct but interacting galaxies, the larger of which has been estimated to be 35% the size of our own Milky Way galaxy.

M51 is still a hot target for professional astronomers, not least because of the black hole that exists within the heart of the larger galaxy.  This central region is undergoing rapid stellar changes and star formation.

Leave a comment


Venus has been a constant jewel in the evening sky recently, popping into view during twilight in the south west and burning with an astonishing intensity in the western skies after darkness.

I’ve been taking my telescope out a few evenings in a row to view the planet from kerb side and marvelled at how well resolved it is at high power.  It’s a half crescent right now, revealing a lovely hazy terminator where Venusian day meets night.  Eager to record its majesty,  I trained my video setup on it this evening, using leg stabilisers and a barrow to maximise the surface area per pixel captured on my Samsung’s CCD chip.  Here’s what I captured.

The visual scale of Venus is impressive here compared to general viewing with eyepiece observation.  This is one of the advantages of having a smaller CCD sensor.  Whilst more limited for large deep sky objects (without focal reduction) it permits big and bold presentations of the planets with just a modest x2 barlow lens.

Notice the pronounced atmospheric haze and refraction of light at the terminator between day and night.  Venus has a thick cloud covered atmosphere which is highly reflective – giving the planet its bright white appearance.  There’s also the slightest hint of mottling or streaking on the surface.  These fine streaks are large cloud structures that ebb and flow slowly within the Venusian atmosphere.

Not so long ago Venus was the target for many pulpy science fiction stories.  These authors imagined the planet full of swamps with dinosaurs and primitive tribes battling across vast continents.  These fantasies were shot down after robotic probe and satellite recognisance of the planet was undertaken, first by the Soviets and later NASA.

Our current understanding of Venus is that it’s a planetary embodiment of hell.  An atmosphere of nearly 96% carbon dioxide traps heat from the sun, raising the pressure to 92 times that of earth, with surface temperatures approaching those inside the finest Italian pizza ovens.  This pizza analogy would apply to any human making it all the way down to the surface of Venus!