Contains:  Solar system body or event
Cabeus Crater - Lunar South Pole region, 


            Bruce Rohrlach

Cabeus Crater - Lunar South Pole region

Acquisition type: Lucky imaging

Technical card

Imaging telescopes or lenses: Skywatcher 200P 200mm/f5 NEQPro6

Imaging cameras: ASI224MC

Mounts: SkyWatcher NEQPRO6 Synscan GOTO

Software: Autostakkert  ·  Adobe Photoshop Lightroom CC  ·  RegiStax 6

Accessory: TeleVue 5x Powermate

Date:June 16, 2019

Focal length: 7000

Seeing: 3

Transparency: 4

Resolution: 12000x9033

Locations: Lysterfield, Melbourne, Victoria, Australia

Data source: Backyard


“Pics de lumiere eternelle” located near the lunar south Pole and imaged from the back verandah in Lysterfield last night. Skywatcher 200mm/f5, ASI224mc, Televue 5x Powermate.

Being a full moon, one is forced to explore the edges of the terminator (boundary between light and dark) which during a full moon lies around the periphery of the lunar disc where the light does not wash out the features and some shadowing is present to show relief.

Courtesy of information from Sky and Telescope, and a NASA article ..... with the lunar axis of rotation being tilted just 1.5 degrees to the ecliptic (compared to Earths 23.5 degree tilt), on the lunar poles the sun is perpetually near or at the lunar horizon. This means the sun never rises above some deep pockets on crater floors near the lunar poles, and they have remained permanently shadowed for billions of years, never seeing the sun. These locations produce some of the coldest recorded temperatures in the entire solar system, around -248 degrees Celcius, cold enough to freeze oxygen and prevent any H2O from sublimating. The corollary of this very small axial tilt is that some of the highest peaks on the south pole crater rims, such as Shackleton and others, experience the sun’s rays around 90% of the time as the moon rotates around its axis. The French astronomer and author Camille Flammarion romanticized these peaks as …. Pics de lumiere eternelle…..”Peaks of Eternal Light”. Most of these semi-permanently illuminated peaks occur around the Shackleton crater, whose name is famously tied to both the Earth and Lunar south poles. The temperatures on these near permanently illuminated peaks are near a constant -50C, rather temperate for their lunar location. But descend to the crater floors and you entire a frigid zone not seen anywhere else (known to date) in the solar system. Due to the permanently shadowed regions at the poles, scientists have theorized that these have acted as “cold-traps” – places where water has frozen into the soil from early in the lunar history and preserved for billions of years without sublimation. NASA launched the LCROSS mission to search for water at the Lunar South Pole in June 2009. On 9 October 2009 the Centaur stage of an Atlas V carrier rocket was purposely impacted into the floor of Cabeus crater (labelled above) followed shortly after by the impact of the LCROSS space-craft itself. Sensors on the LCROSS were used to detect water vapour from the impact plume of the preceding Centaur impact.



Bruce Rohrlach
License: None (All rights reserved)


Cabeus Crater - Lunar South Pole region, 


            Bruce Rohrlach