Search found 7 matches

by Fil
Tue Mar 22, 2016 3:40 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Rainbow Airglow over the Azores (2016 Mar 22)
Replies: 17
Views: 4572

Re: APOD: Rainbow Airglow over the Azores (2016 Mar 22)

Wow! It would be really nice to see an animation of these, if more pictures were taken... To see their evolution. Personally I find it both "strange" and "amazing" that there appears to be a relation between airglow emission and the position of air within the wave (phase). It wou...
by Fil
Sat Sep 07, 2013 10:56 pm
Forum: The Observation Deck: Latest Sky Photography
Topic: Submissions: 2013 September
Replies: 285
Views: 121721

Re: Submissions: 2013 September

Earth-lit Moon, with a crescent painted on it, is rolling Weston the sky, following Teide's silhouette:Image
by Fil
Sun Jun 23, 2013 11:53 pm
Forum: The Observation Deck: Latest Sky Photography
Topic: Submissions: 2013 June
Replies: 224
Views: 132234

Re: Submissions: 2013 June

Hi, Here in Portugal we could not see the Full Moon 21 minutes after perigee at our antipodes, so we could either see it the night before or after its "biggest size". Here are two views from before and after "Super Moon"! 2013-06-22 19:30 UT http://farm6.staticflickr.com/5500/912...
by Fil
Tue May 25, 2010 1:45 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Looking Back Across Mars (2010 May 25)
Replies: 22
Views: 3349

Re: APOD: Looking Back Across Mars (2010 May 25)

I have another question: The tracks left printed on the ground by the rover have a clearly periodic pattern.. I was expecting the tracks to be smooth and constant, as made by wheels in good condition! Does this mean there is a defect on (all) wheels :shock:, or is it an intentional effect, meant to ...
by Fil
Wed Apr 21, 2010 9:11 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Ash and Lightning Above an Icelandic... (2010 Apr 19)
Replies: 48
Views: 14204

Re: APOD: Ash and Lightning Above an Icelandic... (2010 Apr

Artifact of photography. Your reference to different emulsions producing different colors isn't very relevant to a digital image like this. In fact, lightning ionizes nitrogen, which results in the purple color seen here. The main lightning path is saturated, making it appear nearly white. Less bri...
by Fil
Sat Feb 27, 2010 11:52 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Dawn's Endeavour (2010 Feb 27)
Replies: 3
Views: 1552

Re: APOD: Dawn s Endeavour (2010 Feb 27)

Really nice picture! Great framing with the bridges! Does anyone know which direction they were going? Hmm, dumb question, I will check... Judging from http://www.calsky.com , and it seems they both were going from roughly North to roughly SouthEast, so one the image it would mean down from top to b...
by Fil
Thu Aug 06, 2009 2:52 pm
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: A Triple Sunrise Over Gdansk Bay (2009 Aug 04)
Replies: 338
Views: 49720

Re: Cause of Triple Sunrise (APOD 2009 August 4)

In my view, the multiplication of the number of Suns occurs between the camera focal plane and the atmosphere where the Sun gets deformed or where the clouds are. The reason for this assumption is that the extra images of the Sun have this same shape/image. So, unless there is something with a disco...