Mars 17/02 sketch with clean mirror
Posted 17 February 2010 - 01:46 PM
lack of time and being tired, i chose not to set up both scopes, but only the 8" on GEM. seeing was quite good, transparancy as well, and i had the impression the view i got was probably the sharpest or 'best looking' so far this year. perhaps because of the cleaned mirror? mars just looked 'nicer'.
immediately apparent is the shrunken north pole cap and limb haze or clouds at both edges and around the south polar area, left and above Hellas. a lot of dark area around the npc, (hyblaeus and utopia,..) with two darker spots.
Nodus alcyonius was spotted as wel as some fuzzie dark markings at boreo syrtis. a first time for me.
at moments i think to have seen a (small) brightening where elysium is, bordered at the right with a dark streak.
Libya and aethiopis (the areas left of syrtis major) were easily seen as lighter than the other northern dessert plains. aeria, right of syrtis major, looked very dusty or cloudy. syrtis major itself showed detail within in the form of darker streaks. there seemed to be a faint division (hesperia) between mare cimmerium and mare tyrrhenum
good luck with your observations!
Posted 17 February 2010 - 01:51 PM
Posted 17 February 2010 - 01:53 PM
We should all agree to view Mars at the exact same UT date/time and do a sketch. Would be interesting to see each person's interpretation of Mars at the exact same moment
Posted 17 February 2010 - 02:07 PM
Bill: there was even some cat-hair and spiderweb-rag on it as well that's what happens when the scope has been out for half a night about twenty times since last summer with the end cap removed!
i agree about your idea, there are already lots of sketches being posted here to compare our views!
Posted 17 February 2010 - 04:12 PM
Looks like you did a good job with the mirror as well!
Posted 17 February 2010 - 04:27 PM
I'm jealous about the amount of detail you see... maybe I'm going to clean my mirror
Posted 17 February 2010 - 04:43 PM
Posted 17 February 2010 - 08:39 PM
Posted 17 February 2010 - 10:16 PM
I have worked with mirrors that looked worse than yours but one does feel much better knowing the primary mirror is clean. Pinched optics on the other hand can be very bad for good resolution and it does not take much to ruin the view.
Beautiful Mars sketch, I think I like the way it looks above all your other excellent sketches. Much subtle detail as you pointed out.
Posted 17 February 2010 - 10:40 PM
A truly outstanding observation of Mars! You have recorded a wealth of detail over the red planet. This has to be one of the finest observations of Mars of the current apparition. Your Mars observations using a dirty mirror have been excellent but this is your finest to date. I have labeled the major albedo features noted. Thank you for sharing this fine observation with us all.
Posted 18 February 2010 - 11:19 AM
actually this opposition isn't so poor at all Tommy, considering the oppositions to come... i'm kicking myself i quit sketching mars last opposition when it dropped below 12 seconds of arc i now consider anything above 10" 'prime observing time'!
i've seen some similar amount of detail inside syrtis major in the past: sketch 1, sketch 2, sketch 3.
i can only dream about seeing this amount of detail