Nicholas John Shackleton生前是英国剑桥大学地球科学系教授.因为在利用氧-碳同位素研究第四纪气候变化方面的奠基性工作,他于1995年获得Crafoord地球科学奖.他的主要学术成就包括:(1)改进了同位素质谱仪,使得小样品测试成为可能,并确...Nicholas John Shackleton生前是英国剑桥大学地球科学系教授.因为在利用氧-碳同位素研究第四纪气候变化方面的奠基性工作,他于1995年获得Crafoord地球科学奖.他的主要学术成就包括:(1)改进了同位素质谱仪,使得小样品测试成为可能,并确立了深海氧同位素可以作为全球冰量的指标;(2)提供了验证米兰科维奇假说的深海氧同位素关键证据;(3)对建立轨道调谐年代序列作出了突出贡献;(4)在古大洋环流及CO2对全球气候的驱动和响应方面做了开创性研究工作.Shackleton教授被誉为"深海氧同位素之父",他的里程碑式的研究影响着20世纪下半叶古气候的发展历程.本文简要介绍Shackleton教授的学习与科研工作经历、主要的学术成就及成功的素质,希望从中得到一些对中国科学家有益的启示.展开更多
This study focuses on the illumination and temperature at China’s next lunar candidate landing site Shackleton crater.We used the NASA’s SPICE system to evaluate the terrain obscuration effect on real-time illuminat...This study focuses on the illumination and temperature at China’s next lunar candidate landing site Shackleton crater.We used the NASA’s SPICE system to evaluate the terrain obscuration effect on real-time illumination;the resulting illumination map resembles previous studies,validating the methodologies used in our study.In addition,we estimated an accumulated illumination map for the period of likely rover movement.The map indicates the illuminated inner wall of the Shackleton crater is close to 27%of the whole,meaning that the rover will likely receive solar radiation during its movement.Using the real-time illumination and the distributed 1-D thermal diffusion model,we continuously evaluated the regolith temperature for more than 20 years to stabilize the temperature,and selected the temperature of the end time as the initial value used in a thermal study set for July 20,2023 and May 8,2027.Our results indicate the temperature in the permanent shadow region remains nearly constant,thus validating the stability of our estimated initial temperature.Our results also indicate that the surface temperature is more sensitive to transient illumination,but the subsurface temperature is more likely to be associated with the accumulated illumination.This difference indirectly implies that the conductivity of the lunar regolith is inefficient.The locations receiving more solar radiation show a temperature larger than the threshold(~112 K)of ice stability.The permanently shadowed regions can be as cold as 25 K,and such extreme coldness is a hazard to the rover.There are suitable temperature locations which have a warm surface but cold subsurface to preserve water ice.To further ensure normal rover movement,we provided a map of suitable temperature sites and found that these locations exist not only in the Shackleton crater’s inner wall,but also outside the crater.We suggested four trade-off sampling sites with suitable temperatures and gradual slopes.展开更多
文摘Nicholas John Shackleton生前是英国剑桥大学地球科学系教授.因为在利用氧-碳同位素研究第四纪气候变化方面的奠基性工作,他于1995年获得Crafoord地球科学奖.他的主要学术成就包括:(1)改进了同位素质谱仪,使得小样品测试成为可能,并确立了深海氧同位素可以作为全球冰量的指标;(2)提供了验证米兰科维奇假说的深海氧同位素关键证据;(3)对建立轨道调谐年代序列作出了突出贡献;(4)在古大洋环流及CO2对全球气候的驱动和响应方面做了开创性研究工作.Shackleton教授被誉为"深海氧同位素之父",他的里程碑式的研究影响着20世纪下半叶古气候的发展历程.本文简要介绍Shackleton教授的学习与科研工作经历、主要的学术成就及成功的素质,希望从中得到一些对中国科学家有益的启示.
基金funded by the National Natural Science Foundation of China(Grant Nos.41864001 and 42030110)funded by a DAR Grant in Planetology from the France Space Agency(CNES)。
文摘This study focuses on the illumination and temperature at China’s next lunar candidate landing site Shackleton crater.We used the NASA’s SPICE system to evaluate the terrain obscuration effect on real-time illumination;the resulting illumination map resembles previous studies,validating the methodologies used in our study.In addition,we estimated an accumulated illumination map for the period of likely rover movement.The map indicates the illuminated inner wall of the Shackleton crater is close to 27%of the whole,meaning that the rover will likely receive solar radiation during its movement.Using the real-time illumination and the distributed 1-D thermal diffusion model,we continuously evaluated the regolith temperature for more than 20 years to stabilize the temperature,and selected the temperature of the end time as the initial value used in a thermal study set for July 20,2023 and May 8,2027.Our results indicate the temperature in the permanent shadow region remains nearly constant,thus validating the stability of our estimated initial temperature.Our results also indicate that the surface temperature is more sensitive to transient illumination,but the subsurface temperature is more likely to be associated with the accumulated illumination.This difference indirectly implies that the conductivity of the lunar regolith is inefficient.The locations receiving more solar radiation show a temperature larger than the threshold(~112 K)of ice stability.The permanently shadowed regions can be as cold as 25 K,and such extreme coldness is a hazard to the rover.There are suitable temperature locations which have a warm surface but cold subsurface to preserve water ice.To further ensure normal rover movement,we provided a map of suitable temperature sites and found that these locations exist not only in the Shackleton crater’s inner wall,but also outside the crater.We suggested four trade-off sampling sites with suitable temperatures and gradual slopes.
