I’ve recently finished part one of a mini Unity project looking at the stacking behavior of red blood cells in a basic turbulent flow. In this real time simulation you can see how the contact adhesion and stacking rate of red cells increases as plasma Fibrinogen concentrations increase.
Fluid flow was programmed from first principles using some simplified assumptions and custom code generated for red cell attraction and adhesion as a function of plasma content.
This simulation is VR ready so you can don a headset and fly around and study any part of the domain in real time. This simulation can also be ported over to more complex domains.
Stage two of the simulation will include deformation of the red cells during contact with domain walls and other cells.
These stacking effects happen in patients with various blood clotting conditions or super high haematocrits.
Developed By Mackintosh Modelling and Data Simulations
This is an amazing composite image of the Crab Nebula supernova remnant. It shows the neutron star at the center, superimposed over the shockwave nebula (whose outline can be observed dimly in a decent telescope).
This is what happens to high mass stars when they run out of fuel. The atmosphere of the star suddenly collapses inward and dramatically rebounds off the compressed neutron core.
Conservation of angular momentum makes the neutron star spin rapidly (a pulsar) and the rest of the star’s atmosphere expands into space releasing huge quantities of energy (a supernova).
This particular supernova was observed and recorded by Chinese astronomers in 1054 AD as a ‘guest star’, in the constellation Taurus. It remained visible as a naked eye star for over a year before fading.
“Thou lingering star, with less’ning ray,
That lov’st to greet the early morn…”
After last night I’m convinced Rabbie Burns did all his stargazing with a delicious wrap of haggis in hand.
Haggis hand warmers and Clelland’s address from last night’s sellout Dark Sky Burns event. Big thanks to the Abriachan team for the Burn’s supper fare.
Due to inclement skies the astronomy moved indoors I got to talk in some detail about the planet Venus and its harsh environment. A fascinating place that surely deserves more attention in the future, not least for its potential to harbour microbial life in its more clement upper atmosphere.
Why not try looking at Venus through a telescope or a pair of stabalised binoculars? You should be able to make out its phase, just as Galileo did when he first gazed up at it back in 1610.
I can’t get over how much dimmer Betelgeuse in Orion appears at the moment. To my eye Aldebaran (a red giant) in Taurus now appears obviously brighter.
This was an image taken last winter.
Orion image from winter 2019
Many click bait astronomy articles have surfaced claiming the star might be dimming due to its impending collapse and rebound as a supernova, but Betelgeuse is a known variable star and similar changes in its brightness have been noted in the past, although recent changes appear to deviate from established patterns.
Unusual gravitational waves have also been detected in the vicinity of the red supergiant, adding to the sense of mystery. It’s important to note that these waves are merely in the vicinity, so could easily be generated by countless other sources behind Betelgeuse.
Still, it’s fun to speculate about the possibility of witnessing a relatively close supernova event in our lifetime. The last two major naked eye supernovas were recorded in 1572 and and 1054, in Taurus (the Crab nebula) and Cassiopeia (Tycho Brahe supernova). Both generated enough luminosity to be visible in daylight for several weeks, and shone as new ‘guest stars’ for around a year or so before fading.
Some work published by Dolan in 2016 estimated the impact of a Betelgeuse supernova on Earth and found it to be negligible. At 500 light years distance the residual energy of the vastly expanded shockwave would be exponentially diminished as it passed Earth. However the brightness predicted would be magnitude -12.4, making such an event more luminous than a full Moon!
For the mathematically motivated I enclose an extract from his calculations below.
Stargazing can provide mental perspective and wellbeing. Problems we’ve amplified in our heads can seem much less important under the amazing canopy of the night sky.
Here’s some interesting stats to think about.
1. The average person in Scotland spends less than 30 minutes a day outdoors.
2. This equates to over 50 years of an average person’s life spent indoors.
This despite growing levels of stress, anxiety and depression.
Yet one of the best, and absolutely free, ways to alleviate stress and anxiety is being in nature, and stargazing gives us that little bit of extra motivation to head outside, especially during the long periods of darkness we experience over winter in Scotland.
Even if you don’t see anything, packing your binoculars and heading out for an evening stroll under open skies is almost never a waste of time. At the very least you get some exercise, and if you’re lucky, a beautiful night sky to gaze up at.
One of the objects we observed was the star forming nebula in Orion’s sword, imaged here by local aurora hunter and photographer Chris Cogan.
I had a fun astronomy outreach session with pupils and parents from Aldourie Primary near Loch Ness on Friday evening. At 6pm kick off we saw some captivating glimpses of dazzling Venus before it set below the tree line.
Due to initially changeable weather we moved between my indoor presentation and outdoor stargazing, but ended up getting a brilliant spell under the stars mid session.
Despite its relative closeness to Inverness skies are dark enough out here to see the Milky Way very clearly.
Lots of the youngsters (and parents) tried their hand at binocular stargazing for the first time, peering at open star clusters, double stars, the Orion nebula and Andromeda galaxy.
If you’d like to book an outreach session for your school please message me on my facebook site, Highland Astronomy.
The main constellations were visible over the Merkinch nature reserve in the west of Inverness, and even a hint of Milky Way.
We had a great evening at the Merkinch Urban Astronomy gathering tonight. Big thanks to Dr Anthony Luke for delivering a fascinating talk on the chemistry of stars and supernovas. We learnt all about the synthesis of elements and compounds forged in the heart of stars.
Afterwards we were rewarded with clear skies, so I led a group up to the nature reserve for a blustery stargazing session over the Beauly Firth.
Overlooking the water we had lovely views of Orion, the Pleiades and even a hint of the Milky Way and the Andromeda galaxy.
The next event is an Aurora Special on Feb 20th with guest Graham Bradshaw.