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The Classic Moon

beginner classic moon refractor
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#151 sunnyday

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Posted 19 June 2020 - 10:26 PM

superb  work , thanks .


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#152 AllanDystrup

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Posted 20 June 2020 - 03:47 AM

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Dean, Sunnyday -- Thank you! smile.gif

 

     Here are a couple of supplementary maps I generated of the region west of Tycho, including the Heinsius formation and the Hainzel crater group (which I’ll fly past in my next post). Oriented to match my flyby orientation, with N approximately to the right and E down:

 

Tycho West.jpg

*click*

 

    As you can see on the transect below, Heinsius A reaches a good 5 Km below mean lunar surface altitude, while the floor of Tycho is "only" at around 3½ Km depth. Still, sunlight reaches the floor of Heinsius A, so there can be no ice down there. To my knowledge the only definite evidence of water ice on the Lunar surface is from the polar regions, where the very small tilt of the Moon’s rotation axis results in sunlight never reaching the floor of the deepest craters; Here in the perpetual shadow, the temp. is always kept below -157°C (-250° F), and water in the surface layers may therefore be preserved from earlier eons in the lunar history.

 

Heinsius Transect.jpg

*click*

 

     -- Allan


Edited by AllanDystrup, 21 June 2020 - 12:05 AM.

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#153 AllanDystrup

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Posted 20 June 2020 - 08:20 AM

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The Daylight Moon, May 14 2020 at 09:30 AM
[2]: Schickard - Capuanus

    

    

    Looking straight ahead in the flight path of my LEM, I now approach the Marsh of Epidemics and the Lake of Fear; I have definitely no intention of touching down here though, but there are a couple of surface features that draw my attention: first there’s the Hainzel crater group between Schiller and Capuanus, and further up towards the lunar horizon, the large but shallow Schickard crater (227 Km Ø, 1.5 Km depth).

    

2020-06-14 3 Schickard - Capuanus.jpg

*click*

 

    

     Located at the NE edge of the degraded pre-Nectarian crater Mee is seen a trefoil of overlapping craters: the largest and oldest (Nectarian) being Hainzel, the younger C and the youngest A. The terraced walls of Hainzel A and its ejecta carpet into C and out over the NE part of Lacus Timoris can be seen; These indicate an Eratosthenian age for Hainzel A, while Hainzel C must be older, -- anywhere from Imbrian age or possibly formed almost simultaneously just prior to A in an oblique cometary impact.

    

Hainzel Transect.jpg

*click*

         

     The crater floor of Schickard was lava flooded in the upper Imbrian epoch, and shortly thereafter covered by light hued highland material excavated and thrown out by the Orientale Basin impact; Subsequently additional lava eruptions have covered the NW and SE parts of the floor in dark mare basalt, leaving a broad wedge of the Orientale ejecta to be seen in the central part.

    

     -- Allan

 


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#154 AllanDystrup

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Posted 21 June 2020 - 06:34 AM

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The Daylight Moon, May 14 2020 at 09:30 AM
[3]: Byrgius – Gassendi
[4]: Rook Mts. – Grimaldi

    

    
     I end my daylight flyby over the waning Moon with a couple of views out the right window of my imaginary LEM; In this illumination, there are a couple of very bright spots which immediately draws my attention; They turn out to be two young Copernican impacts that each has thrown out a brilliant web of ejecta rays over the lunar landscape: the first is Byrgius A, and further up, past Grimaldi and Rainer Gamma, is Olbers A.

 

     Equally conspicuous in the high sun are some dark areas, formed by a couple of unnamed mare patches S of Vieta and in the Nectarian Zupus crater, plus a pair of lava-filled craters further up N in the Imbrian impacts: Billy and Crüger.

 

BYRGIUS.jpg
*click*

    

      

     Leaning forward towards the window and looking up further N, past Byrgius A and Billy - Crüger, I can faintly trace out the double-ringed impact basin of Grimaldi as well as the eastern rim (the Cordillera and Rook Mt. chains) and the lava-filled trenches (Lacus Autumni and Aestatis) of the far-side Orientale impact basin. These features are however not suitable for a detailed study right now, due to the low resolution and an unfavorable lunation.

 

GRIMALDI.jpg
*click*

 

     -- Allan


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#155 AllanDystrup

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Posted 21 June 2020 - 06:46 AM

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The Daylight Moon, May 14 2020 at 09:30 AM
[5] Olbers A – Reiner γ

    

    

     Past Grimaldi I can glimpse the Reiner Gamma magnetic swirl and the Olbers A crater. Reiner γ shows its two tails, the brightest up N and the fainter and more broken up swirl down S. Olbers A has thrown out bright ejecta rays predominantly up NNW, indicating an oblique impact coming in low from SSE. The brightest ray across Procellarum is seen from the crater Cardanus up N to Seleucus (the Seleucus Ray)

 

OLBERS-A.png

*click*

    

    
     Thus ended my imaginary flight in the LEM in orbit from the center of the Moon down towards the SW horizon. As previously mentioned, the observations here were done from Earth grin.gif in broad daylight at ~10 AM local time, and so the contrast of my views were significantly reduced as compared to a nighttime observing session. Never the less it was possible for me – in a long stretch of overcast and rainy weather – to seize the opportunity for a quick lunar observing session which was both enjoyable and also inspired me to research a couple of surface features that I had not paid attention to before.

    

     My observations were done through my small 4” refractor, both visually at 50x (TV 13mm EP), and for close-ups using my small FLIR CM3 industrial cam in live mode, while for documentation taking a series of 40s AVIs (that were later AS!2 stacked to PNG images). The camera was placed after a 4x barlow yielding 300x mag, which was too much for the daylight and seeing conditions (a 2x barlow would have given sharper images), -- but I had a cloud cover closing in from the east, so I chose to stick with the barlow at 4x mag and see what I could catch before curtain fall.

 

     -- Allan


Edited by AllanDystrup, 21 June 2020 - 06:47 AM.

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#156 AllanDystrup

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Posted 20 July 2020 - 06:56 AM

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The 18 day (84%) waning gibbous moon.

    

    

     It’s the start of July, just past midnight local time (2020-07-09 01:30 CEST, UT+2). I’m out in my suburban backyard on the northern outskirts of Copenhagen, Denmark. I’m located at 56° N latitude and currently in astronomical dawn with a “city sky” of SQM ~18.6 (NELM 5.4). The temperature is a cool 10°C, the dew pt. down at 6°C, the humidity is 75% and the Moon is on the rise, but still low at ~10° altitude in Aquarius towards the SE.

    

     The lunar libration is [+7° Lat, +3½° Long], so the NE limb of the Moon is well exposed tonight. The transparency and seeing are both hampered quite a lot by the low altitude and the atmospheric humidity, so the views are quite soft, but I decide to take a sweep down the terminator anyway, and see what I can catch. I’m pressing my 4” refractor to the limit with a Baader FFC @ 4x barlow, for ~300x magnification in a ~6 arc’ FOV.

    

2020-07-09 01.00 Moon 18.3DY Overview.jpg
*click*

 

 

To be continued…

     -- Allan


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#157 AllanDystrup

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Posted 20 July 2020 - 07:01 AM

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18-Day MOON: 1. N. Polar region (West)

    

    

     In the north polar region, the large old (Pre-Nectarian/Nectarian) walled plains Pascal, Anaximenes and Goldschmidt are conspicuous, as are the young Copernican craters Carpenter, Philolaus and not the least Anaxagoras with its long bright ejecta rays cast out west and south across Mare Frigoris.

    

     The “King in the North” must however be the large walled plain Hermite, with part its floor in permanent shadow, where LROC has recorded the coldest temperature in the solar system of 26°K (the coldest spot recorded on Pluto is 43°K). The triplet of craters just W of Hermite can also be glimpsed: Sylvester, Haber and even Lovelace, which I have not seen before. The North Pole itself is to the E, just outside my image, on the back rim of the crater Peary.

 

2020-07-09 01.00 Moon 18.3DY 1 North Polar region W.jpg
*click*

    

Tbc / -- Allan


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#158 AllanDystrup

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Posted 21 July 2020 - 01:11 AM

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18-Day MOON: 2. Lacus Mortis

    

    

     Between the two young (Eratosthenian-Copernican) crater pairs of Aristoteles-Eudoxus and Hercules-Atlas, the most conspicuous feature is the large ancient (Pre-Nectarian) complex crater: Lacus Mortis. The crater floor and the eastern rim were lava flooded in Upper Imbrium, as were the floors of the younger, partly overlapping pair of craters Plana-Mason that impacted in the Nectarian epoch right on the southern crater wall of Lacus Mortis.

 

     Much younger of course (Copernican) is the crater Bürg with a central peak, terraced walls and an ejecta carpet with highland rocks excavated from below the dark lava cover. Also seen is the Shannen Ridge, which was described as late as 2009 by Maurice Collins based on Kaguya laser altimeter data (LALT). It is a 630 km long and 430 m elevated ejecta ridge radial to the Imbrium basin.

    

18DY 2.Lacus Mortis.jpg

*click*

    

     -- Allan


Edited by AllanDystrup, 21 July 2020 - 01:15 AM.

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#159 AllanDystrup

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Posted 23 July 2020 - 12:26 AM

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18-Day MOON: 5. Nectaris

    

    

     Here I'm looking down at the central part of the Nectaris Basin that has a thin cover of upper-Imbrian mare lava, which has also flooded the large Fracastorius crater at the S end. The view is fully inside the basin ring #4 marked by the prominent Altai Scarp (not seen here), but the three inner rings can be glimpsed: from Santbech to Cyrillus, the Pyrenees Mts. and (faintly) the mare wrinkle ridges.

    

     Besides Fracastorius are seen several other large Nectarian craters surrounding Mare Nectaris, notably: Cyrillus, Catharina and Santbech, and on top of that: the younger impacts of Theophilus and Colombo, both with well-preserved terraced walls and ejecta carpets.

     

     A couple of interesting formations are seen above M. Nectaris: the large promontorium Mons Peck W of Theophilus, and the Imbrian-sculpture feature Vallis Capella through the Capella crater N of Nectaris and down towards the tormented Gaudibert crater cluster.

    

 

8DY Moon 5 Nectaris.jpg
*click*

    

     -- Allan


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#160 AllanDystrup

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Posted 24 July 2020 - 01:44 AM

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18-Day MOON: 6. Piccolomini, Janssen.

    

    

     Here I'm looking down at an old, mostly Pre-Nectarian area of the lunar surface just S of the Nectaris basin, delimited by the Altai Scarp and younger Piccolomini and Neander craters.

    

     Towards the W is a semi-circle of big battered PN-craters (Zagut, Rabbi Levi, Riccius), and in the south is seen the large complex landscape of the old Janssen-Brenner-Metius craters with young Eratosthenian Fabricius on top. Inside Fabricius can be glimpsed its characteristic horseshoe shaped down-slided terrace towards the NE.

    

     S of Neander can be seen a ridge, that continues in the Rheita Valley (a radial Imbrium feature). N of the Janssen complex I noticed a couple of arcuate surface features that could be interpreted as signs of an old basin rim (?), but more likely are just random alignments; -- our brain is geared to try "connecting the dots" in nature...

    

18DY Moon 6 Piccolomini-Janssen.jpg

*click*

     -- Allan

 


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#161 Organic Astrochemist

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Posted 29 August 2020 - 12:10 AM

Thanks Allan for continuing this great thread.

I really like your use of LROC Quickmap. I had a quick peek at Sinus Iridum last night (84% illuminated) and seeing the elevation on Quickmap really helped me to appreciate what I was seeing.

Sinus Iridum

The plain gently slopes down, casting a shadow, until the mountains suddenly rise over 3 km into the blazing sun producing a beautiful bright crescent around the bay.


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#162 AllanDystrup

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Posted 01 September 2020 - 07:30 AM

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Organic Astrochemist -- interesting! The Iridium crater wall has a rise of 2.5 Km over a distance of ~25 Km, -- that's a slope of 9 dg... I think the steepest gradient in the Tour de France bicycle race is ~11 dg, so you should still be able to drive a good lunar rover uphill over the crater rim (of course that would be cheating lol.gif).

     

     

12 Day Waxing gibbous Moon.

     

     It’s the end of August, just around midnight local time (2020-08-30/31, 23.00-01.00 DST CEST (UT+2). The 12-Day 95% waxing gibbous moon is hanging at a low 11.9° altitude in Capricorn, just past the meridian towards the S horizon. Here at 56°N 12°E in Denmark we are now crossing the border from Summer to Autumn, with a fresh temperature of 13°C, 80% humidity and the dew-point down at 9°C. The seeing is a bit wavering around 4-5/10, and the transparency is ~medium at 4-5/7, with a faint halo around the moon from the high atmospheric humidity plus a sheet of medium-altitude Stratocumulus stratiformis covering half the night sky (but not the moon, currently).

     

     I’m out, barefoot and in shirtsleeves, in my Copenhagen suburban backyard with the 7” f/10 Mak. telescope for a closer look at the lunar terminator: from Mare Frigoris, further on through the E Procellarum area with the Aristarchus plateau and the Marius hills, and down to the cratered southern highlands with the large prominent Schickard  crater. The full disc view is pretty good at low magnification, using a 2x barlow plus a 41mm Panoptic for 88x, but it gets softer as I push up the magnification to 140x with my small ASI120MC camera.

     

     

Lunar Lavas.jpg

2020-09-01 12-DY Moon full disc.jpg

*click*

To be continued...

     -- Allan


Edited by AllanDystrup, 01 September 2020 - 07:36 AM.

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#163 AllanDystrup

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Posted 02 September 2020 - 01:44 AM

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12 Day Waxing gibbous Moon.

Continued

 

2020-09-01 12DY Moon Frigoris.jpg

2020-09-01 12DY Moon Aristarchus - Schickard.jpg

*click*

 

     -- Allan


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#164 AllanDystrup

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Posted 06 September 2020 - 02:21 AM

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8-Day Moon

     

     

     It’s an early evening in late August, just after 9 PM (2020-08-26, 21:00 local DST, CEST UT+2) , and here at 56°N latitude we’re right now at the border between civil and nautical dusk. The 8-day half (62%) waxing gibbous moon is hanging low at 9½°, just clear of the tree line but down in the haze towards  the S horizon. The atmosphere is rather unsteady, and so with below medium transparency and seeing plus a Bortle 5 (NELM 5.7) suburban dusk sky, this is far from optimal conditions to observe the Moon.

 

     But HEY! It’s a nice late-summer evening with a comfy 17°C temperature after a week with showers and a forecast promising another cloudy and rainy week, so let’s pull out the scope for a moon walk down the lunar terminator!
 

8DY Moon 2020-08-26 21.00 Overview.jpg

*click*
    

     -- Allan


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#165 AllanDystrup

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Posted 06 September 2020 - 05:51 AM

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8-Day Moon, [1] East Imbrium.

     

     

     In East Imbrium, several wrinkle ridges are seen in the lava flows: one ridge from Mons Spitsbergen stretching up W of Kirch and continuing N to Mons Pico, and another lava surf breaking  against the crater wall of Piazzi Smyth, then wiggling up N to the crater wall of Plato.

     

     The light hued Apennine Bench SE of Archimedes is made, partly of igneous rock erupted on the basin floor, and partly of landslide blocks from the Apennine basin wall, when the excavated floor was uplifted soon after the Imbrium impact (leaving steep-sloped mountain faces like Huygens, Bradley and Hadley). In the following upper-Imbrian lava flooding, only part of the Apennine Bench was submerged, including the floor of Archimedes and the low area now known as Palus Putredinis. The young craters Aristillus and Autolycus showing distinct ejecta carpets were created later, by Copernican impacts in the Mare Imbrium lava plains.

 

8DY Moon 2020-08-26 21.00 Overview N.jpg
*click*

 

     -- Allan


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#166 AllanDystrup

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Posted 06 September 2020 - 05:57 AM

.     

8DY Moon 2020-08-26 21.00 1A.jpg
*click

   
    -- Allan


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#167 AllanDystrup

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Posted 06 September 2020 - 05:59 AM

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2020-09-06 12_53_21-8DY Moon 1B.jpg
*click*

     -- Allan


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#168 AllanDystrup

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Posted 07 September 2020 - 08:02 AM

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8-Day Moon  [2] Aestuum, Vaporum, Medii

     

     

     The landscape N of the Central Bay (Sinus Medii) is dominated by a couple of dark mantle deposits (DMD) from lava eruptions; -- most obvious in this image are the DMD on the 3 parallel rubbly hilly ridges of Imbrium ejecta N of the Hyginus crater, -- and you can spot some of the fire fountain vents in the collapsed lava channel known as the Hyginus Rille.

     

     Also glimpsed on the image are the narrow intertwined Triesnecker Rilles, probably mare lava cracks pulled apart by uplifting caused by rising mantle material.

     

2020-09-26 21.00 8DY Moon 2A.jpg

*click*

 

     -- Allan


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#169 AllanDystrup

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Posted 10 September 2020 - 08:50 AM

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8 Day Moon, south terminator.

     

     

8DY Moon 2020-08-26 21.00 Overview S.jpg

*click*

     -- Allan


Edited by AllanDystrup, 10 September 2020 - 09:01 AM.

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#170 AllanDystrup

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Posted 10 September 2020 - 08:59 AM

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8-Day Moon:  [3] Great Peninsula (W)

     

     

     Several long furrows/troughs are slicing through the highlands in the W part of the Great Peninsula, all radial to the Imbrium Basin and thus of course all Imbrium Sculpture features.

     

     In the low sun along the terminator, the smooth floor of the 153 Km wide pre-Nectarian Ptolemaeus walled plain shows several small 5-10 Km craters that have been almost fully covered by a combination of intruding mantle magma plus Imbrium Basin impact melt and pulverized ejecta; These craterlets are now only detectable as shallow hollows ("saucers") in the walled plain of Ptolemaeus. I've marked five of the more obvious saucers, including the largest one, named Ptolemaeus B.

     

     The nearby but younger (Nectarian) walled plain craters Alphonsus and Albategnius also show overall smooth floors, Alphonsus with both signs of volcanic activity (rilles, dark-haloed craters) but also a striking diagonal ridge of Imbrium ejecta, and Albategnius with a couple of saucers, just like Ptolemaeus.

 

 

8DY Moon 2020-08-26 21.00 3A.jpg
*click*

     

     -- Allan


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#171 AllanDystrup

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Posted 12 September 2020 - 07:35 AM

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8-Day Moon:  [3] Great Peninsula (W) 
continued: Deslandres, Purbach, Regiomontanus, Walther

     

     

     Deslandres is an ancient (pre-Nectarian) 256 Km wide, walled plain (or small lunar Basin); It is heavily degraded, and was in early lunar cartography only marked as “Hell Plain” after the family of “Hell” craters on the Deslandres impact floor. There’s a line of 5 craterlets: a Catena, at the NE quadrant of the Hell Plain, pointing south towards a small group of young craterlets including Hell-Q with a light hued halo of ejecta known as Cassini’s Bright Spot (best seen at full moon). Well seen on the image is also a valley (a Graben) that extends from the center of Deslandres down SE, cutting through the N crater wall of Lexell.

     

     Purbach and Regiomontanus are a couple of other old (pre-Nectarian) and battered craters, bordered on the south by the younger (Nectarian) and more well-preserved crater Walther. Purbach and Regio both have a relatively smooth floor filled in by ejecta from later impacts, which have left only breached saucer-like crater rims (like Purbach W). The central peak of Regio has a craterlet (A) at the summit, which before the Apollo era by some (like Patrick Moore) were interpreted as a volcanic vent, but spectral analysis has since determined that the central peak is made of not basalt but just normal highland rock. At the impact of Walther, the E crater wall pushed into the smaller Nonius crater, leaving an unusual triangular depression.

     

     Many other details can be seen in this area, -- to mention a few: the floor of Blanchinus streaked with ejecta from Werner, the landslide from Nasireddin into Miller, the Werner White Spot on the N crater wall around crater D (best seen at high sun), part or the Werner-Airy fossil basin, and “The” so called Lunar X (which is just one random alignment of 4 craters, of which there are countless forming any figures you can imagine, from the alphabet to eyes, faces etc. and so on...).

     

2020-09-26 21.00 8DY Moon 3B.jpg

*click*

 

     -- Allan

     

 


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#172 AllanDystrup

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Posted 02 October 2020 - 02:15 AM

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The 23-day Moon.

     

     

     It’s past midnight this early morning at the end of September (2020-09-30, 01:00 Local DST, CEST UT+2), and I have been out trying to observe the Perseus Molecular Cloud complex (Per MCC); Though the seeing is good (8/10), the transparency is only ~medium (4/7), and with a high haze in the atmosphere plus an almost full Moon at 27° altitude in Aquarius, the sky is rather “washed out” and not really suitable for DSO.

     

     So, after a short observation of IC348 at the eastern end of the Per MCC, I swing over my 4” refractor towards the Moon to see what is on display up there tonight. The lunation is close to full Moon (12.6 days), so the “usual suspects” at the terminator towards the W lunar limb are well illuminated: from the Rümker volcanic complex and the Gruithuisen viscous magma domes, past the Aristarchus Plateau nicely dusted with mustard colored pyroclastic deposits, and down to the Marius Hills region and the Rainer Gamma Swirl.

     

     What’s most interesting tonight, however, is that the libration is tilting the NE quadrant towards the Earth, which offers a very good view of the Humboldtianum Basin. I can in fact see all of Mare Humboldtianum with the Hayn and Bel’kovich craters to the north and the jagged up-tilted Humboldtianum basin rim at the horizon. The Marginis and Smythii mares are also well exposed tonight -- what a wonderful sight! I take a few quick iPhone snapshots through my 13- and 8mm eyepieces, but I’m too tired for a closer up study of Humboldtianum combined with some proper camera shots (-- which I regret today, but as we say in Denmark: “There’s always another bus and another girl coming by”. And another Moon, of course...)

     

2020-09-30 13-Day Moon.jpg

*click*

     -- Allan


Edited by AllanDystrup, 02 October 2020 - 02:15 AM.

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#173 AllanDystrup

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Posted 07 October 2020 - 05:17 AM

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The 18-Day Moon

     

     

     It’s an early morning in the start of October (2020-10-05, 04:30 Local DST, CEST UT+2), and I have been out in my suburban backyard a good hour observing Mars with Syrtis Major at display right at the central meridian. The waning 17.8 day (91% illuminated) gibbous Moon is now sailing up at 45° altitude in Taurus towards the south just past the meridian, so I chose to close the night with a quick scan of the  lunar surface.

     

     The two most striking features at this illumination are: the W basin rim of Crisium, which looks like a space monster has taken a bite out of the “crumbling celestial cookie”..., plus the many light hued ejecta rays from young Copernican cratering impacts, crisscrossing the highlands and dark mares:  from Anaxagoras in the N, past the splosh of Aristillus in E Imbrium and down to the big splash of Tycho in the S cratered highland.

     

     Also well illuminated on the 18-day Moon are the lava fills in the Nectarian epoch Serenitatis Basin, with the oldest lava fill seen as a broad light-hued patch at the center of the basin (Unit III, mid-Imbrian ~3.4-3.3 Gyr), and the younger, darker and smoother lava plains (Unit II, early Eratosthenean 3.2-3.1 Gyr ) located along the N and E shore. A couple of  local regions show up with Dark Mantle Deposits (DMD) of ash from fire fountains, notably in the Taurus-Littrow area and along the SW shore from Sulpicus Gallus and up.

     

     The bright ejecta ray across Mare Serenitatis from Menelaus past Bessel is obvius; Looking at a cross section of the Menelaus crater, it does seem like it could have been created by an oblique impact coming in from the W and digging out a non-symmetrical crater interior with a roughly N-S butterfly ejecta pattern (like that seen around Procleus W of Crisium). On the other hand, the N “Bessel-ray” also seems to align well with the Tycho crater impact as the origin, so I guess the votes are still out on this lunar feature...

     

18DY MOON N 2020-10-05.jpg

18DY MOON N Serenitatis 2020-10-05.jpg

*click*

     -- Allan


Edited by AllanDystrup, 07 October 2020 - 06:11 AM.

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#174 AllanDystrup

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Posted 08 October 2020 - 03:05 AM

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     And here's the big "splash" of the Copernican Tycho impact into the cratered southern highands. The dark doughnut halo of impact melt splashed out around the Tycho crater wall is well seen at the center of radial spokes formed by light-hued excavated highland rock; The two main ejecta rays are located in a butterfly pattern: one up NW and the other down SW, indicating that the impactor came down in an oblique path from the W. I’ve looked at transects of the Tycho ejecta rays, clearly visible in W Nubium, -- but the material is so pulverized that it is hard to discern on a transect profile.
     
     A couple of other noteworthy surface details in this observation are the wedge of surface deposits in central Schickard (an ejecta ray 
from the Orientale impact), and the two “white spots” most prominent near full moon: Cassini’s white spot in central Deslandres (“Hell Plain”) plus the bright spot on top of the N crater rim in Werner; The first is the bright halo surrounding the young crater Hell Q, while the latter is ejecta from the high-albedo craterlet Werner D.

     

     There's also a bright region where the SW main “butterfly-ray” from Tycho (stretching down S between Longomontanus and Clavius) has coated the mountainous region at the SSW horizon around the Le Gentil crater. The jumbled mountains in this region rise up 4-6 km above the crater floors.

     

      

18DY MOON S 2020-10-05.jpg

*click*

     

     -- Allan


Edited by AllanDystrup, 08 October 2020 - 03:14 AM.

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#175 AllanDystrup

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Posted 15 October 2020 - 01:51 AM

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22-24 Day MOON
Daytime view of Orientale Basin

     

     
     The large 3-ringed Orientale Basin is the result of a young Imbrian impact, featuring two large craters in the central lava-fiilled interior: Maunder and Kopff. The crater Kopff is right on 90° W longitude, so the Orientale Mare with Maunder and the far side of the basin rings are all “beyond the bend” so to speak, out in the western libration zone.

        

     Here’s a view of the Orientale region from October 11. 2020, showing first the main features in perspective as seen through my 4” refractor, and then for comparison a “rectified” view based on LROC:: Quickmap data:

 

 

22DY Moon 2020-10-09 2x Orientale daytime.jpg

22DY Moon 2020-10-09 4x Orientale daytime.jpg

*click:

     

LROC Orientale.jpg

     

     To-be-continued...
     -- Allan

 

 

 


Edited by AllanDystrup, 15 October 2020 - 02:05 AM.



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