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Unmanned Spaceflight.com _ Telescopic Observations _ Amateur ISS spotting

Posted by: Stu Mar 22 2009, 12:25 PM

Been watching the ISS go over the past couple of nights and it's now fantastically bright. Many amateur astronomers are now training their 'scopes on the ISS and photographing it, achieving stunning results like this...

http://spaceweather.com/submissions/large_image_popup.php?image_name=Quintus-Oostendorp-iss210309-flare_1237676263.jpg

Interesting to see how golden and shiny the new panels are in those images... have the others been "dulled" by exposure to the environment of space, or is there some other reason..?

Posted by: ilbasso Mar 22 2009, 01:16 PM

A quick reply before this topic gets shut down ... rolleyes.gif

I think the color difference is a result of the angle of reflection - notice that it's only one side of the new panels that are golden, as are the same side of the S5 panels, which have been up there for a while.

Posted by: Stu Mar 22 2009, 01:38 PM

I think this topic is pretty safe; I am just talking about visual observations through a telescope, not passing comment on manned spaceflight issues.


Posted by: AndyG Mar 22 2009, 01:57 PM

What I've found surprising about the recent - gorgeous! - views, is that it's undeniably different to point-source stars and little satellites, yet human visual acuity suggests 100m at (my latitude's average) 700km range is j-u-s-t below the point at which "size" becomes apparent.

Mind you, that's on a par with crescent Venus, so presumably it's a "large source" partially overcoming "twinkling-atmospheric-turbulence" thing?

Andy

Posted by: Tesheiner Mar 22 2009, 02:13 PM

I have to agree with Ilbasso that the effect is due to angle of reflection and the first picture is the best example. The second image (actually a composite) is not so overexposed and the different pointing of each individual array wing can be easily seen.

Posted by: Stu Mar 22 2009, 02:15 PM

Good explanations. I just wondered. smile.gif

Posted by: Hungry4info Mar 22 2009, 05:52 PM

It's definitely just reflection angle that makes the solar arrays a different colour. Note that colour differences are observed between the 'forward' and 'aft' section of the solar array wings, however for a single solar array wing, both the front and back section has been in space the same length of time.

The colouration of the arrays in the linked images is thus inconsistent of being affected by the length of time they were in space.

Posted by: Decepticon Mar 22 2009, 05:56 PM

Can binoculars see that kind of detail?

Is 30x enough to see some detail?

Posted by: imipak Mar 22 2009, 09:49 PM

We've had nice clear skies here for the last couple of nights, and I helped my parents see their first ISS passes last night (mag -2.3) and tonight (-2.4.) Tonight Dad came equipped with some rather elderly but good quality 30x binoculars, with which I /think/ I could just about discern an H shape... although it could have been wishful thinking. Both experimental subjects reported their surprise at it's brightness and clarity, and that they found it interesting and enjoyable. (They've spent much of today calling round various friends and family excitedly suggesting they take a look, too. Hey, it's a quiet village!)

It's amazing how simple outreach can be. $heavensabove++ !

I'm starting to have crazy daydreams about trying to get framegrabs from a cheap webcam plus some kind of telescope, and learning how to stack frames. Some of the ground-based images out there are astounding (and of course there are plenty of interesting unmanned s/c to try to get!) Anyone here tried it? [Edit - snip unfortunate evidence of why UMSF does not go with G&T sad.gif ]

Posted by: ngunn Mar 22 2009, 11:00 PM

I'd like to say thanks to Stu for the reminders about when to look. I've been looking with x10 binoculars. It moves fast and anything more would make it pretty hard to catch without clever automation. X10 is easily enough to see some shape.

Posted by: Decepticon Mar 23 2009, 03:16 AM

I had 2 chances tonight.

It's was to fast for any detail.

Posted by: remcook Mar 23 2009, 08:07 AM

I saw ISS on Friday. It was amazingly bright. Quite a sight.

Posted by: AndyG Mar 23 2009, 10:05 AM

A quick google suggests there is definitely "shape" with image-stabilised binoculars of 12 times magnification.

Andy

Posted by: 4th rock from the sun Mar 23 2009, 10:17 AM

I've tried with 10x50 binoculars on tripod and the station moves too fast through the field of view to see any details.
Using my hands, even with a firm support, I never saw any defined shape.
Perhaps my old Hi8 video camera with 10x image stabilized optical zoom might record something :-)

Nevertheless the view is tremendous with the naked eye alone... specially if the shuttle is close to the station. Then you get to see both moving through the sky in tandem. Awesome sight.

Posted by: ngunn Mar 23 2009, 10:48 AM

QUOTE (4th rock from the sun @ Mar 23 2009, 10:17 AM) *
Using my hands, even with a firm support, I never saw any defined shape.


I don't use an external support but instead use my hands to clamp the binoculars firmly to my head. The head is better at smooth panning than the arms are.

Posted by: Decepticon Mar 23 2009, 03:22 PM

QUOTE
Perhaps my old Hi8 video camera with 10x image stabilized optical zoom might record something :-)


Interesting! I'm gonna try that and see what happens.

Posted by: Sunspot Mar 23 2009, 11:32 PM

Had a great view of it here this evening, Also some flaring during the first pass in twilight - maybe mag -4 plus

Posted by: Stu Mar 23 2009, 11:38 PM

Really nice view of ISS from Kendal tonight, during its 20.14 pass. Managed to follow it in my 4.5" 'scope, and magnified 20x or so it was very noticeably an elongated object. No detail visible, but not stellar. One nice flare too, really stunning to look at.

Posted by: James Sorenson Mar 24 2009, 12:48 AM

I have been meaning to catch the new sight of ISS for the last few days now. However clouds are a nuisance when it comes to looking up at the heavens above sad.gif .

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