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Re: Streaks hypothesis
Posted: Wed Aug 15, 2007 12:08 pm
by LIVbase13
progan01 wrote:I was all set to accept MaG's Iridium flare explanation, then I checked the orbits via NASA's JTrack (
http://science.nasa.gov/Realtime/JTrack ... ack3D.html). All the listed Iridiums are in polar orbits. That does not explain these west-to-east streaks. If they are satellites, they are not the Iridiums MaG noted.
Well, the picture was taken 04:28:23 (local time I guess) and if you consult a star map, you'll see that the Pleiades are direction EAST. If the camera was pointing East the objects were going north-south - so it could be Iridiums in polar orbit. But it could also be a number of other satellites.
Kind regards LIVbase13
About the composite image
Posted: Wed Aug 15, 2007 12:29 pm
by canopia
Hello, I am the photographer of today's APOD.
First of all, I am sorry not to be able to write sooner. And below is what I can say about the image.
We were observing at Beynam, Ankara, Turkey (the location data can be found at
http://www.heavens-above.com).
The streaks in the picture you see comes from 5 different pictures I took, at 04:23-04:25, 04:31-04:33, 04:41-04:43, 04:51-04:53 ve 04:59-05:01 GMT+3, in the morning of 12th August (not 13th). I aligned the streaks according to the background stars they passed. (You can see the effects of composition in the picture.)
When the first meteor stroke, one friend said, "If you could not catch this, I will lose my respect in this photography," and we are sure it was a meteor. And we thought it to be a Perseid. Why not? It was the Perseid night.
When examining the images I came across the repeated streaks in the series (I took 100 of these pictures using the camera and lens combination you already know) it was clear that satellites were a possibility. (But we did see the first one as a meteor, remember.) I guess, either a satelite or a meteor, the streak cut right at the bright edge was recorded just at the beginning of the exposure, as the ones we saw were moving from left to right.
And we did see two satellites moving parallel, of one I later confirmed to be Iridium, not at the part of sky you see the streaks, but 25 degrees to the right, in Eridanus.
And, I found out other mentioned possible Alpha Ursae Majorid streaks in other images and "not in Orion". Had I not found those, I would be in much doubt, maybe never posting the image at all.
Last, I submitted the image data (and original images themselves) to Dr. Josep Maria Trigo, a researcher of these subjects.
I hope this helps. Good day,
Tunç Tezel
Posted: Wed Aug 15, 2007 12:42 pm
by quarkcsj
40 minutes?
Posted: Wed Aug 15, 2007 12:42 pm
by eboily
Multiple possibilities:
- 1. It is 40 seconds, not minutes. Using a short enough focal length, no star trail should be visible. which is the case.
2. It is 40 minutes, unguided. Then we would observe star trails.
3. It is 40 minutes guided, then the trees would be blurred.
4. It is 40 minutes guided and the trees have been photoshopped in. But the horizon lights seems to indicate otherwise.
5. Other possibilities like multiple superposed exposures but again, the trees would be blurred.
I think the first possibility is the most probable. It is consistent with the unblurred trees, the lighting of the sky near the horizon, the mointaintop light and the crisp trail-less stars. The exposure time is more likely 40 seconds.
- Edouard
Posted: Wed Aug 15, 2007 1:11 pm
by FieryIce
Re: About the composite image
Posted: Wed Aug 15, 2007 1:11 pm
by quarkcsj
canopia wrote:Hello, I am the photographer of today's APOD.
The streaks in the picture you see comes from 5 different pictures I took, at 04:23-04:25, 04:31-04:33, 04:41-04:43, 04:51-04:53 ve 04:59-05:01 GMT+3, in the morning of 12th August (not 13th). I aligned the streaks according to the background stars they passed. (You can see the effects of composition in the picture.)
Tunç Tezel
This really clears things up.
So it was 5 images from 04:23 to 05:01, (thus the 40 minute Span) that were 105 second exposures.
I'm guessing that (just) the streaks were superimposed on an image that was only a 56 second exposure though, as the EXIF data indicates.
Posted: Wed Aug 15, 2007 1:13 pm
by orin stepanek
I can't tell what it is; but it looks like a spot light could be shining on some power lines that may be a little wet or icy.
Orin
Posted: Wed Aug 15, 2007 1:16 pm
by quarkcsj
I think maybe you are mistaking his Sabre for the Belt. The 3! Belt Stars are almost straight up and down in this image.
The 4! stars that are at a 45 degree angle is his Sabre.
Posted: Wed Aug 15, 2007 1:18 pm
by pjsuther
Clearly the streaks are from a large glass, ridged object reflecting the light given off by the light source at the horizon. Stealth technology at its best, undoubtedly using transparent superconducting materials - I'd be curious to know how far the nearest US air base is from where these images were taken.
Posted: Wed Aug 15, 2007 1:20 pm
by Dirty25RS
In response to APOD saying there was a microburst meteor shower happening simulatenously i would like to post my observations of that night. I was outside with 3 other people and trying to explain that all the perseids would appear to radiate from a single point in perseus, but i was having a hard time backing that claim becuase there were meteor falling in all different directions that night! Made me look stupid.
Posted: Wed Aug 15, 2007 1:26 pm
by quarkcsj
Dirty25RS wrote:In response to APOD saying there was a microburst meteor shower happening simulatenously i would like to post my observations of that night. I was outside with 3 other people and trying to explain that all the perseids would appear to radiate from a single point in perseus, but i was having a hard time backing that claim becuase there were meteor falling in all different directions that night! Made me look stupid.
Here's one report from my club:
Gretchen and I went to the Ulumaika Park in Kahala (not too far
from our Kahala Park observing site. We got there around 10:15pm
and didn't see any Perseids until about 11:27pm when we saw a
really nice earthgrazer. Little did we know that was to be the best
one we saw all night!! We finally left the park around 1:00am. We
probably saw less than 6 real Perseids, altho we did see a few
sporadics. The clouds would roll in periodically and we got a few
light showers, but there were some really nice open times. We were
pretty much disaapointed in what we saw.
Posted: Wed Aug 15, 2007 2:15 pm
by crateocrickets
So, where any actual meteors captured (or harmed) in this photo?
Re: About the composite image
Posted: Wed Aug 15, 2007 2:19 pm
by MaG
canopia wrote:
We were observing at Beynam, Ankara, Turkey (the location data can be found at
http://www.heavens-above.com).
The streaks in the picture you see comes from 5 different pictures I took, at 04:23-04:25, 04:31-04:33, 04:41-04:43, 04:51-04:53 ve 04:59-05:01 GMT+3, in the morning of 12th August (not 13th). I aligned the streaks according to the background stars they passed. (You can see the effects of composition in the picture.)
Tunç Tezel
Hi, thank you for your better comments.
As you can see now, your words are in very good agreement with times from Calsky..
I submit: Location Beynam near Ankara, Time: 4:00 - 7:00 local time.
and I receive this in Calsky.com:
4:23:26 Iridium 35, -1,9 mag (in Orion)
4:32:45 Iridium 97, -4,7 mag (in Orion, spare satellite, time and mag can be inaccurate)
4:42:04 Iridium 5, -2,6 mag (in Orion)
4:51:19 Iridium 6, +1,2 mag (in Orion)
So we have only one problem - what was at 4:59 - 5:01?
Calsky says nothing in Iridium flares section..
..so now I searched all satellites in eastern Orion between 4:59 and 5:01 up to 9 mag! And I saw - Iridium 7, mag 8,3 exactly in the same position and line as in your image (fifth weak line on the top)! That means, I think, this Iridium 7 satellite flashes some small flare to you and Calsky means, that this flare is too dimm that he did not tell me.
When you can, I can send e-mail with sky maps form Calsky, where are all these Iridium flares - all are in the same positions as in photo of the day
(sorry for my bad english)
![Smile :)](./images/smilies/icon_smile.gif)
meteor shower
Posted: Wed Aug 15, 2007 3:06 pm
by tom2688
i had the great fortune to be in the las vegas area during the last great meteor storm ( i think it was winter 2004 ). the view of all those meteors falling at the same time was awsome. unfortunately i didn't have a camera that could take time exposures, now i do. when can we expect another meteor storm again??? thanks in advance for the info. tom.
Mystery Solved
Posted: Wed Aug 15, 2007 3:53 pm
by canopia
I have just looked the flares up, with the exact location of our observing site found by google maps ans satelite images, and the predicted Iridium flares were within a degree of the streaks in the pictures. Mystery is most probably solved.
One should be alert for Iridium series like this even if it is not a meteor shower night.
So long for these five Alpha Ursae Majorids
![Rolling Eyes :roll:](./images/smilies/icon_rolleyes.gif)
But still, I have 2 ot 3 more non-Perseid streaks in consistence with the radiant of this shower.
This high-ISO-DSLR setup with a wide angle lens is a good tool for meteor observing.
Good day,
Tunç Tezel
PS: Don't despair about your language skills, it is just fine.
![Wink :wink:](./images/smilies/icon_wink.gif)
-------------------
>When you can, I can send e-mail with sky maps form Calsky, where are all these Iridium flares - all are in the same positions as in photo of the day
>(sorry for my bad english)
![Smile :)](./images/smilies/icon_smile.gif)
[/quote]
Posted: Wed Aug 15, 2007 4:05 pm
by DM
C'mon everyone -- take a closer look --
![Shocked :shock:](./images/smilies/icon_eek.gif)
-- it's clearly a light shining on wires (the top wire being lightning protection, as usual).
Posted: Wed Aug 15, 2007 4:35 pm
by Andy Wade
DM wrote:C'mon everyone -- take a closer look --
![Shocked :shock:](./images/smilies/icon_eek.gif)
-- it's clearly a light shining on wires (the top wire being lightning protection, as usual).
Well that could be cleared up really easily if canopia were to take a look during the day to see if there are any overhead wires in this position.
Alternative Explanation
Posted: Wed Aug 15, 2007 4:36 pm
by Pzoxic
The first thing that I thought of when I saw the picture was that it might possibly an atmspheric effect, similar to green flares, striped suns, etc... at sun/moon set or rise.
Under certain atmospheric conditions (strange temperature gradients) a sunset can like like a stacked set of lines parallel to the horizon. See for example:
http://www.atoptics.co.uk/atoptics/smir7.htm
I think that longer exposures might exagerate this effect. It is hard to judge from the pictue how close the flashes are t the horizon, they should be pretty close for this to occur.
Considering the brightening horizon, this might be due to a sunrise (if the picture was taken to the east), or of a moonrise or set (what time did the moon rise and set in turkey that night?).
Also I am wonderring what the bright light o the hilltop on the lower right of the picture is.
Of course, they're probably just satelites...
Posted: Wed Aug 15, 2007 4:50 pm
by DM
looking at previous posts, I agree that:
if it's forty minutes there should be star trails, but Iridium series is possible
if it's forty seconds, there is insufficient time for 5 Iridiums to pass
someone noted that the image was edited with Photoshop 7
I still think it's a high powered flashlight shining on overhead wires is most likely
Posted: Wed Aug 15, 2007 5:03 pm
by productivity_zero
Did anyone say Streetlight yet?
More answers
Posted: Wed Aug 15, 2007 5:16 pm
by canopia
* The bright light on the horizon is a forest fire observation tower. There used to be an unwelcome mercury lamp there. But it somehow went off and never fixed again, much to our delight.
* There are no power lines there, take my word.
Good day,
Tunç Tezel
Posted: Wed Aug 15, 2007 5:20 pm
by Bunghole Jones
I totally spanked it all over that cosmic streetlight. Thanks for the pic fap fap fap
Non-Perseid meteors during the night of 12/13 August
Posted: Wed Aug 15, 2007 5:56 pm
by GGaskill
I am a not very experienced observer who was located at approximately 35° 13' N, 117° 26' W, facing to the northeast and observing from 2130 12 Aug to 0200 13 Aug (times are PDT.) Almost half of the meteors observed did NOT come from the Perseid radiant but from the west (behind me) including the most brilliant one.
Its a Streetlight
Posted: Wed Aug 15, 2007 6:00 pm
by teknocrat
Being an expert on Streetlights and nighttime streetlight photography I can clearly tell by the blur in the photo that it is a miaoyu GDJ4111 Model of streetlight most likely with a sulfer bulb.
Posted: Wed Aug 15, 2007 6:31 pm
by avicenna
I am very glad to find that amongst all the talking back and forward (It's powerlines, no it's Iridium flares no it's photoshop) there are a few people who, like me, come out and say they saw lights streaking across the sky in the wrong direction.
I feel much less of a fool now. I also read the whole discussion - and found that not everybody does.
Good skies tonight!