"A moment of lunacy"?

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rwilkinson
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"A moment of lunacy"?

#1 Post by rwilkinson » Wed Feb 16, 2011 9:24 am

This is the event which I mentioned at last night's meeting:
isstransit2.jpg
Lunar transit of the ISS from Bolton on 16-Feb-2011 (shown with "Stellarium" program)
isstransit2.jpg (34.25 KiB) Viewed 6453 times
Yes, from a small area of the Earth's surface - in this case within a few miles to the South and West of Bolton - the International Space Station could be seen silhouetted against the Moon.
But as it was still raining when I went to bed at 11pm, I didn't get up to check if it had cleared over by 00:57am (it had by 04:30).
This would have been a "blink and you miss it" event, lasting only about 0.7 sec, but I think that it should have been observable through binoculars or a small 'scope.

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Re: "A moment of lunacy"?

#2 Post by rwilkinson » Wed Feb 16, 2011 11:42 am

I used Ed Morana's free Java program:
http://pictures.ed-morana.com/ISSTransits/predictions/
to predict this event.
It produces a ground-plot of the area of visiblilty which can be displayed in GoogleEarth or on a GoogleMap - here's the map for last night's event:
16feb.jpg
Ground-track for ISS transit on 16-Feb
16feb.jpg (118.27 KiB) Viewed 6451 times
The blue line is the centre, and the two red lines are the limits of visibility.

And there's another one predicted on Saturday morning, visible on the North side of Bolton, and Bury (one for Carl?):
19feb.jpg
Ground-track for ISS transit on 19-Feb
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Possible ISS transit on 7-Mar

#3 Post by rwilkinson » Sat Feb 26, 2011 8:08 am

The latest simulation runs predict an ISS transit of the Moon around 5:45pm on Mon 7-Mar, which could be visible from the South side of Bolton.
At this time the Sun will be just setting so the ISS will be sunlit, and the Moon is a thin crescent, so it may be a tricky observation.
But even if you're outside the transit zone, it's probably the best chance to spot the ISS in daylight?
I'll post updates here nearer the time, as we get more accurate predictions...

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Re: "A moment of lunacy"?

#4 Post by rwilkinson » Mon Mar 07, 2011 12:53 pm

Here's the predicted ground-track for tonight's event:
7mar.jpg
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and the sky is clearing...

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Re: "A moment of lunacy"?

#5 Post by rwilkinson » Mon Mar 07, 2011 1:14 pm

Although I'm not in the transit zone, it should still be worth a look from central Bolton:
7mar.jpg
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Looks like a job for binoculars on a tripod?

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Re: ISS/lunar conjunction on 7-Mar

#6 Post by rwilkinson » Mon Mar 07, 2011 6:54 pm

Yes, I saw it! :-)

As it was fairly low in the West, I had to set up my binoculars in the "side passage":
binoculars.jpg
binoculars.jpg (111.02 KiB) Viewed 6393 times
The thin crescent Moon was surprisingly difficult to find at first in the daylight sky, but I soon had it in the top half of my 7x50 field-of-view.
There were a few high-flying aircraft in the area too, but exactly at the appointed second I saw the ISS pass by, to the South of the lunar disk. It was bright enough to show against the early twilight sky, and crossed my binocular field in a couple of seconds, but I could still make out a sort of "T"-shape (the main body with the two solar arrays extended).

Did anyone else see it - or even take a picture?

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