Session 5 for 2022

[Davesellars]

Session 13th Jan
Scope: 12" Dob

Session 5 for this year was moon observing!  I'm a complete noob at observing the Moon  Therefore I spent a bit of time on google and found a good page listing 12 targets:

https://astronomy.com/news/observing/2020/01/explore-12-great-lunar-targets

I popped these targets in to Sky Safari and added a couple of others for good measure...  prepared, it was time to start around 9pm.

For this part I started with the Pentax XW 5mm but quickly switched to a 4mm TMB Optical Planetary II giving 300x

Clavius - Not too far away from the terminator this was showing really clearly.  Craterlets J,N,Y,C,D,T,X and K all very clear.  I enjoyed the "route" walking down from this towards Tycho via Maginus.

Plato - Perhaps not the best (too much illumination?) for attempting to see the small craterlets however I could just about make out some pock-marks in the extremely flat featureless crater.

Archimedes - Nice visual on this spotting a couple of the craterlets.  The nearby Montes Spitzbergen highlighted especially well.

Thor's hammer - Not the offical name (as it doesn't see to have one).  However it a feature just to the south (normal way up) of Mons Piton that looks unmistakenly like a mallet.  Not too difficult to see but it rather an impression on the surface that needs the sharpness and reasonable power to make out the shape well.

Back down to Plato it's a short stroll to...

Sinus Iridum (Bay of Rainbows) - OK, this feature blew me away.  I think it may have been ideally situated(?) with the close terminator - following the length of the bay a great amount of features embedded into it particularly from Bianchini crater to Laplace D.  One of the most awesome features of this bay was Promontorium Laplace - on the bay side of this cape starts looks to be a meandering valley which is of reasonable length.  To the west of this (dob view) some "footprints" left in the otherwise flawless bay.

Copernicus - Obviously two central craterlets and ridges on the edge of the main crater.  Montes Carpatus nicely detailed below this (dob view).   As I strolled then towards the terminator from Copernicus I was intrigued by Montes Riphaeus which stood out beautifully illuminated although it does not appear to be a particularly prominent mountain range.

Rimae Gassendi - This one was spectacular - the closeness to the terminator really highlighted the depth of this feature and the central mountains inside the crater which there seemded to be 4 individual mountains although clumped together - The 3D effect was really quite outstanding.

Rimae Hadley - One of my extras as it was the site of the Apollo 15 landing site and I was particularly after seeing the "stream" that runs through that area.  I'd got the area in view however the clarity was disappearing fast...  I looked to see where the problem was and sure enough my secondary mirror had succumbed to dew.  In fact, the air was so damp that everything was soaked with water.  This feature will have to wait until next time!

 

 

 

[Franklin]

Do you use a Neutral Density or Polarising filter?

[Davesellars]

Hi Franklin.  No filter used.  It wasn't necessary with the 4mm eyepiece as it was sufficiently dimmed not to be painful.  Having said that though..  I may have to invest in one as in normal conditions I wouldn't be abe to use that power.

Edited January 17, 2022 by Davesellars

[Kon]

Very nice report. I think the 13th was the best seeing I had of the moon as well; it easily took x360 magnification in my 8" Dob and it remained sharp.