Moon's rotation axis from the orbit plane of earth is about 1.54° tilted. Just like earth because of tilt, do polar regions experience 6 months day and 6 months night?

If so, aren't these places ideal for landing site as you may get power throughout 6 months[In case you dont have RTG's]

  • 1
    $\begingroup$ Yeah lunar obliquity to ecliptic is what I wanted to refer. Yeah thanks I shall edit it $\endgroup$
    – zephyr0110
    Feb 5, 2019 at 16:06
  • $\begingroup$ I still get confused about the lunar system's geometry! $\endgroup$
    – uhoh
    Feb 5, 2019 at 23:18

1 Answer 1


As Uhoh stated, the 1.54 degrees 'Lunar Obliquity to Ecliptic' is more important here. I'm not exactly sure of the length of time that sunlight occurs, but there are elevated locations on the southern pole that experience sunlight for far longer than most places during the Lunar day. According to Air and Space Magazine's 'New Light on the Lunar Poles' article:

We had a poor understanding of polar topography until the Japanese Kaguya mission flew in 2008. The Kaguya spacecraft made a detailed laser altimetry map of the entire Moon, including both poles. From this precision topographic data, we made a simulated relief model of the poles and illuminated it as the real Moon would be illuminated by the Sun over the course of a year. Our new results suggest at least four areas near the south pole are in sunlight for large fractions of the lunar day. One location (B) is illuminated more than 82% of the lunar day and is only 10 km from another point (A) that is lit 81% of the day. Moreover, these two points are complementary in that the dark times at one corresponds to sunlit times at the other. The four topographically high sunlight points are collectively illuminated 100% of the time during the lunar seasons.

Image of locations described in article

As you said, these locations are good places to land, not only because of near-constant sunlight but because thermal variations are limited in comparison to lunar day.

  • 2
    $\begingroup$ That's a really beautiful image! $\endgroup$
    – uhoh
    Feb 5, 2019 at 14:23
  • 1
    $\begingroup$ As I understand it, there are nearby points (inside the craters) that are never illuminated. These are (a) places where moisture might gather and (b) great telescope sites $\endgroup$ Feb 6, 2019 at 15:09
  • $\begingroup$ @SteveLinton indeed. I believe there have been some satellites pointed at the craters which show a higher concentration of hydrogen in the area, which may point to water ice. $\endgroup$
    – jos
    Feb 7, 2019 at 13:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.