Peak of eternal light
A peak of eternal light (PEL) is a hypothetical point on the surface of an
Detailed lunar topography collected by the Lunar Reconnaissance Orbiter (LRO) suggests that no points on the Moon receive perpetual light during both the winter and summer. However, there are points on crater rims which have very extended periods of sunlight.[3][4]
On the Moon
Orbital survey
The ESA SMART-1, NASA Clementine and JAXA SELENE spacecraft made maps of the lunar poles that have been used to identify sites receiving eternal light. The orbiting craft monitored the lighting at the poles and looked for seasonal variations, as well as mapping the relief so that peaks of eternal light could be identified topographically.
The Lunar Reconnaissance Orbiter then took a data set including 24,000 wide-area camera and 31,500 narrow-angle camera images within 2° of the poles. These were used to construct high-resolution maps that reveal illuminated terrain under varying lighting conditions.[3]
Lunar north pole
Based on images from the
Lunar south pole
The lunar south pole is situated in a huge depression, leading to 16 km altitude differences over the region. Careful analysis of imagery and topographic conditions on the lunar South Pole by teams from NASA and the ESA revealed a small number of illuminated ridges within 15 km of the pole, each of them much like an island of no more than a few hundred meters across in an ocean of eternal darkness, where a lander could receive near-permanent lighting (for ~70–90% of the southern lunar winter, and likely all of the southern lunar summer).[6]
The Malapert Mountain region, on the rim of the
The data set from Lunar Reconnaissance Orbiter shows that some sites on the rim of Shackelton remain illuminated for 94% of a lunar year. The longest all three Shackleton outposts are eclipsed is 43 h.[3]
Approximate placement near a named feature |
Lunar coordinates |
Illuminated time fraction | Notes | ||
---|---|---|---|---|---|
Over lunar year 2020 |
Minimum per lunar day |
Maximum per lunar day | |||
On Shackleton Crater ridge: point A |
166.0°W |
89.68°S81% | 44% | 98% | Even during the worst lunar day the longest period of darkness is ~7 Earth days, with shortest periods of light between darkness of ~3 Earth days |
Peak near Shackleton Crater ridge: point B |
141.8°W |
89.44°S82% | 56% | 100% | During worst lunar day the longest period of darkness is ~12 Earth days; has 4.5 lunar days of continuous lighting in lunar summer and only 4.5 Earth days of total darkness time in 8 lunar days. |
on De Gerlache Crater ridge: point C |
68.7°W |
88.71°S85% | 64% | 98% | Has shortest period of darkness of only ~6 days, followed by ~7 days of intermittent light and darkness periods. |
Peak close to Shackleton Crater ridge: point D |
124.5°E |
88.79°S86% | 58% | 100% | 5 lunar days of continuous light, ~7 lunar days lighting with only ~2 Earth days of darkness, ~12 Earth days periods of darkness or near darkness during lunar winter. |
on Malapert Mountain: point M1 |
2.7°E |
86.04°S74% | 54% | 95% | |
on Malapert Mountain: point M2 |
2.9°W |
86.00°S74% | 58% | 90% |
In culture
- Moon Temple planned for a peak of eternal light on Shackleton crater's rim to address future needs (such as spiritual accommodation) of people living on the Moon
- 2017 — European Space Agency artist in residence Jorge Mañes Rubio created initial design[9]
- 2018 — corresponding artifacts were created by the ESA Advanced Concepts Team
See also
- Crater of eternal darkness
- Extraterrestrial sky
References
- ^ Beer, Wilhelm, and Mädler, Johann Heinrich (1837). Der Mond nach seinen kosmischen und individuellen Verhältissen oder allgemeine vergleichende Selenographie. Berlin, Simon Schropp and Co. (in German).
- ^ Flammarion, Camille. Astronomie Populaire, description générale du ciel. Paris, 1879. (in French).
- ^ a b c Speyerer, Emerson J., and Robinson, Mark S. (2013). "Persistently illuminated regions at the lunar poles: Ideal sites for future exploration", Icarus, 222, No. 1, January, pp. 122–136.
- ^ Gläser, P., Oberst, J., Neumann, G. A., Mazarico, E., Speyerer, E. J., Robinson, M. S. (2017). "Illumination conditions at the lunar poles: Implications for future exploration", Planetary and Space Science, vol. 162, p. 170–178.
- .
- ^ Kruijff, M. (2000). The Peaks of Eternal Light on the Lunar South Pole: How they were found and what they look like, 4th International Conference on Exploration and Utilization of the Moon (ICEUM4), ESA/ESTEC, SP-462, September.
- ISBN 978-0-7844-0625-0.)
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: CS1 maint: multiple names: authors list (link - ^ doi:10.1016/j.icarus.2010.03.028.)
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: CS1 maint: multiple names: authors list (link - ^ "Peak of Eternal Light". jorgemanesrubio.com. May 9, 2018. Retrieved December 28, 2023.
External links
- Koschny, Detlef; Grieger, Björn. "Taking a SMART sidelong look at Peak of Eternal Light". Europlanet Research Infrastructure. Archived from the original on 2011-09-29. Retrieved 2009-09-24.
- The Peak of Eternal Light video by the European Space Agency.