DeepSkyFreak
Aktives Mitglied
Hallo Leute,
Ich habe eben das "Unmoegliche" versucht und - ich nehme es gleich vorweg - Erfolg gehabt:
Details auf Ganymed bei 1026x.
Also, ich habe weder Malaria noch hat mich ein Meteorit getroffen :biggrin: Die Bedingungen waren heute perfekt!
Temperatur 28 C um 22 Uhr LT :schwitz:, 67% Luftfeuchtigkeit, kein Wind, Jupiter hoch im Sueden (ich bin ja hier auf 14 Grad Nord) und Super-Seeing.
Das Equipment: 15" Obsession, 5 mm Nagler und 3x Powermate.
Ich poste hier meinen Original-Eintrag in mein Log - ist halt in Englisch... Danach geht's wieder ans Okular.
With very good seeing and clear skies I thought that it would be worth trying to scan Jupiter's biggest moon for details. I had attemped the "impossible" before with magnifications of up to approximately 500x but did not succede. Weather conditions were also very favourable today with 28 C and 67% humidity at 2200 local time. No wind. The temperature inside the house was around the same, so the mirror would be in perfect condition for the observation. I first trained the scope towards the moon at 342x magnification, to see how good the seeing was. Ahhh, steady, just a tiny little bit of low frequency wobble. I increased the mag to 732x (7mm Nagler + 3x Powermate). I was amazed to still get sharp views. OK, one more final increase to 1026x (5mm Nagler + 3x Powermate). Craters and shadows still sharp - unbelievable!! Right - Jupiter now. The first glimpse of Jupiter at 732x was disappointing, though. Lack of contrast and by far not as many details as I expected. Well, Jupiter is tricky and contrast is absolutely essential to see a lot of detail. Actually, I saw more at 342x... Now I had no more hope for more. Nevertheless I pointed the scope at Kallisto first. Wow - what a beautiful dark, tiny disk. I was stunned by the color that reminded me of pictures right away. Then Ganymede: Geee, like a tiny Mars! Beautiful orange and already fairly big at 732x. After some 10 minutes and waiting for seconds of very steady seeing, I thought that it had seen hints of shading on Ganymede. Now go for it! 1026x... It almost blew me over when I realized that there are shadings visible on that "not-so-tiny-anymore" disk. What I saw was basically a cone-shaped dark area that ran through the center of the moon. The northeastern and southeastern parts of the disk (scope direction) were distinctly brighter than the area around the equator of ganymede. In moments of perfect seeing I could spot a very dark tiny patch southeast of the disk's center. Now I will have to find out what part of Ganymede I saw and then compare my sketches to maps. The date and time of the observation was 2 hours ago, 14 Aug 08 at 14 - 1500 UT from Kanchanaburi, Thailand. Wow, I am still breathless... Post the observation and go out again for more!
CS
Armin
Ich habe eben das "Unmoegliche" versucht und - ich nehme es gleich vorweg - Erfolg gehabt:
Details auf Ganymed bei 1026x.
Also, ich habe weder Malaria noch hat mich ein Meteorit getroffen :biggrin: Die Bedingungen waren heute perfekt!
Temperatur 28 C um 22 Uhr LT :schwitz:, 67% Luftfeuchtigkeit, kein Wind, Jupiter hoch im Sueden (ich bin ja hier auf 14 Grad Nord) und Super-Seeing.
Das Equipment: 15" Obsession, 5 mm Nagler und 3x Powermate.
Ich poste hier meinen Original-Eintrag in mein Log - ist halt in Englisch... Danach geht's wieder ans Okular.
With very good seeing and clear skies I thought that it would be worth trying to scan Jupiter's biggest moon for details. I had attemped the "impossible" before with magnifications of up to approximately 500x but did not succede. Weather conditions were also very favourable today with 28 C and 67% humidity at 2200 local time. No wind. The temperature inside the house was around the same, so the mirror would be in perfect condition for the observation. I first trained the scope towards the moon at 342x magnification, to see how good the seeing was. Ahhh, steady, just a tiny little bit of low frequency wobble. I increased the mag to 732x (7mm Nagler + 3x Powermate). I was amazed to still get sharp views. OK, one more final increase to 1026x (5mm Nagler + 3x Powermate). Craters and shadows still sharp - unbelievable!! Right - Jupiter now. The first glimpse of Jupiter at 732x was disappointing, though. Lack of contrast and by far not as many details as I expected. Well, Jupiter is tricky and contrast is absolutely essential to see a lot of detail. Actually, I saw more at 342x... Now I had no more hope for more. Nevertheless I pointed the scope at Kallisto first. Wow - what a beautiful dark, tiny disk. I was stunned by the color that reminded me of pictures right away. Then Ganymede: Geee, like a tiny Mars! Beautiful orange and already fairly big at 732x. After some 10 minutes and waiting for seconds of very steady seeing, I thought that it had seen hints of shading on Ganymede. Now go for it! 1026x... It almost blew me over when I realized that there are shadings visible on that "not-so-tiny-anymore" disk. What I saw was basically a cone-shaped dark area that ran through the center of the moon. The northeastern and southeastern parts of the disk (scope direction) were distinctly brighter than the area around the equator of ganymede. In moments of perfect seeing I could spot a very dark tiny patch southeast of the disk's center. Now I will have to find out what part of Ganymede I saw and then compare my sketches to maps. The date and time of the observation was 2 hours ago, 14 Aug 08 at 14 - 1500 UT from Kanchanaburi, Thailand. Wow, I am still breathless... Post the observation and go out again for more!
CS
Armin
