Wednesday 30 November 2016

TIME FOR SOME SIRIUS STUDY

It is St Andrew's Day, November 30th. Before the day is out I must share my story of my November night sky observations.

For much of the month the weather has been remarkably bright and clear both during the day but also at night. On several occasions  when I was up during the night I observed a bright white light ... and as I reported to Iain in the morning ... the light had a port and starboard light on either side.  Weird ... but that is how I saw it on repeated occasions.


It was in the south-east and low in the sky. I could not hear a plane coming overhead, nor find any planes arriving at Glasgow airport (using Flighttracker24). 

I mentioned this to a few folk over the weeks and got interesting responses:  "Yer mad Woman!" (Iain) .... through to ...  "Get yourself a star chart and see what lines up. (Alastair).
 

Well, it is a star! This website* clinched it for me when it said  "anyone familiar with the constellation Orion can simply draw a line through Orion’s Belt, to the left. "  The star is Sirius and appears, especially in November  in the northern latitude, low in the sky and very bright.


This photo is the position of these stars as seen from the back garden.

But what about the colour? I had never realized that stars could twinkle in colour.  They do, and Sirius can be seen with any number of colours; it has been given the name The Rainbow Star.

And the following explains how this occurs:

The brightness, twinkling and color changes sometimes prompt first-time observers to report Sirius as a UFO. But these changes have nothing to do with Sirius. Rather, they are what happens when such a bright star as Sirius shines through the blanket of Earth’s atmosphere. The light from Sirius, which often appears fairly low in the sky from the mid-north latitudes, passes through a long column of air before it reaches our eyes. Changes in density and temperature of this air affect the light and cause the flickering and shimmering we see when we gaze at this star. This happens for other stars, too, but it is more noticeable for Sirius because it is so bright, and because it appears low in the sky.
 * Ref:  http://www.universetoday.com/110605/sirius-ufo-trickster-extraordinaire/

* * * * * * * * * *  

While I was fascinated to learn about this star I also learned 2 other striking things:

[1] In my report of this sighting (I genuinely believed I was looking at a plane coming in toward me as we live on a flight path for Glasgow Airport but the flights are not usually from that south-east direction) I used descriptive words which skewed my 'report'.  If I had said I saw a white shining light with red and green on either side I might have had a different/better/less shrill reaction.  But having seen exactly that kind of light at sea (ships in the distance coming towards us, or, indeed, passing far away on the horizon heading for some port or other) I used that terminology and unwittingly affected the outcome.

[2] This observation could form a nice little kernel for a sociological study on personality types!  Glass half full people reactions vs Glass half empty reactions!


[Thanks to Jane in Kelowna for this wine glass image!]

Later - some feedback:  you omitted to give the Engineer's take on the glass half full situation which is "the glass is twice as large as it needs to be"!!!!




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