China's Mars probe,named Tianwen-1,including an orbiter and a landing rover,will be launched during the July-August 2020 Mars launch windows.Selected to be among the rover payloads is a Subsurface Penetrating Rada...China's Mars probe,named Tianwen-1,including an orbiter and a landing rover,will be launched during the July-August 2020 Mars launch windows.Selected to be among the rover payloads is a Subsurface Penetrating Radar module(RoSPR).The main scientific objective of the RoSPR is to characterize the thickness and sub-layer distribution of the Martian soil.The RoSPR consists of two channels.The low frequency channel of the RoSPR will penetrate the Martian soil to depths of 10 to 100 m with a resolution of a few meters.The higher frequency channel will penetrate to a depth of 3 to 10 m with a resolution of a few centimeters.This paper describes the design of the instrument and some results of field experiments.展开更多
Mars orbiting,landing and roving are expected to be achieved during China’s first Mars exploration mission,disclosed at the working meeting of the rover system for the mission held on March 1,2017.The mission,covers ...Mars orbiting,landing and roving are expected to be achieved during China’s first Mars exploration mission,disclosed at the working meeting of the rover system for the mission held on March 1,2017.The mission,covers a complicated process,requiring large technical leaps,many critical links and huge engineering challenges,is of great significance in promoting advancement of space technology and展开更多
Hydrated minerals provide direct indications of the early Martian water environment. The various clay minerals and evaporite salts found to date are mainly exposed in the ancient southern highlands of Mars. While it i...Hydrated minerals provide direct indications of the early Martian water environment. The various clay minerals and evaporite salts found to date are mainly exposed in the ancient southern highlands of Mars. While it is believed that the area of the northern lowlands could have hosted a global ocean in the past, its surface is covered with a layer of spectrally nonabsorbing materials, and orbital hyperspectral remote sensing has found only sparse evidence for the presence of water. China's first Mars exploration mission, Tianwen-1, landed in the putative ancient shoreline zone of the northern lowlands of Mars. Its rover,Zhurong, conducted high-spatial-resolution reconnaissance to reveal the geological and environmental evolution of this region.Owing to frequent dust storms, not only is the Martian surface covered with dust, but also the spectral calibration panels on the rover are affected by dust coverage. Data from the shortwave infrared(SWIR) spectrometer onboard the rover are also affected by other environmental factors such as instrumental temperature changes and atmospheric carbon dioxide absorption. This study recalibrated the in situ SWIR data to minimize the impact of the above factors. The recalibrated spectral data show that the reflectance of the landing area falls within the normal range of Martian soil, and confirm the presence of several important absorption peaks. The absorption characteristics indicate the presence of polyhydrated sulfates, gypsum, and hydrated silicates in the surface materials along the rover track, with sulfate content of <27–39 wt.%. Our results further confirm past activity of liquid water in the Zhurong rover landing area, providing mineralogical evidence supporting hypotheses related to underground water or an ancient shoreline.展开更多
A new object-oriented method has been developed for the extraction of Mars rocks from Mars rover data. It is based on a combination of Mars rover imagery and 3D point cloud data. First, Navcam or Pancam images taken b...A new object-oriented method has been developed for the extraction of Mars rocks from Mars rover data. It is based on a combination of Mars rover imagery and 3D point cloud data. First, Navcam or Pancam images taken by the Mars rovers are segmented into homogeneous objects with a mean-shift algorithm. Then, the objects in the segmented images are classified into small rock candidates, rock shadows, and large objects. Rock shadows and large objects are considered as the regions within which large rocks may exist. In these regions, large rock candidates are extracted through ground-plane fitting with the 3D point cloud data. Small and large rock candidates are combined and postprocessed to obtain the final rock extraction results. The shape properties of the rocks (angularity, circularity, width, height, and width-height ratio) have been calculated for subsequent ~eological studies.展开更多
Mars may once have been a wet place where life could flourish,according toNASA scientists who say a robot rover has found evidence that rocks on the RedPlanet“were once soaked with liquid water.” 【原译】据美国宇航...Mars may once have been a wet place where life could flourish,according toNASA scientists who say a robot rover has found evidence that rocks on the RedPlanet“were once soaked with liquid water.” 【原译】据美国宇航局的科学家报道:火星过去可能有丰富的水资源,生物能在那里蓬勃生长。展开更多
尽管人类生存的地球麻烦不断,但是人类探索外层空间的努力始终没有松懈。前不久,又一颗“流浪者”挣脱地球之引力飞往火星。就凭这一句(Afternine balloons have deployed,completely enveloping the landing craft,it will bouncealong...尽管人类生存的地球麻烦不断,但是人类探索外层空间的努力始终没有松懈。前不久,又一颗“流浪者”挣脱地球之引力飞往火星。就凭这一句(Afternine balloons have deployed,completely enveloping the landing craft,it will bouncealong like a toy on the Martian surface as much as a mile before coming to rest.)便足以让我们展开想象之翅膀!展开更多
基金support from the China National Space Administration.
文摘China's Mars probe,named Tianwen-1,including an orbiter and a landing rover,will be launched during the July-August 2020 Mars launch windows.Selected to be among the rover payloads is a Subsurface Penetrating Radar module(RoSPR).The main scientific objective of the RoSPR is to characterize the thickness and sub-layer distribution of the Martian soil.The RoSPR consists of two channels.The low frequency channel of the RoSPR will penetrate the Martian soil to depths of 10 to 100 m with a resolution of a few meters.The higher frequency channel will penetrate to a depth of 3 to 10 m with a resolution of a few centimeters.This paper describes the design of the instrument and some results of field experiments.
文摘Mars orbiting,landing and roving are expected to be achieved during China’s first Mars exploration mission,disclosed at the working meeting of the rover system for the mission held on March 1,2017.The mission,covers a complicated process,requiring large technical leaps,many critical links and huge engineering challenges,is of great significance in promoting advancement of space technology and
基金funded by the National Key Research and Development Program of China (Grant No. 2022YFF0504000)the Key Research Program of the Chinese Academy of Sciences (Grant No. ZDBS-SSW-TLC00106)+1 种基金the Key Research Program of the Institute of Geology and Geophysics, Chinese Academy of Sciences (Grant No. IGGCAS-202102)the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant No. 2023071),the Young Elite Scientists Sponsorship Program by CAST (Grant No. 2021QNRC001)。
文摘Hydrated minerals provide direct indications of the early Martian water environment. The various clay minerals and evaporite salts found to date are mainly exposed in the ancient southern highlands of Mars. While it is believed that the area of the northern lowlands could have hosted a global ocean in the past, its surface is covered with a layer of spectrally nonabsorbing materials, and orbital hyperspectral remote sensing has found only sparse evidence for the presence of water. China's first Mars exploration mission, Tianwen-1, landed in the putative ancient shoreline zone of the northern lowlands of Mars. Its rover,Zhurong, conducted high-spatial-resolution reconnaissance to reveal the geological and environmental evolution of this region.Owing to frequent dust storms, not only is the Martian surface covered with dust, but also the spectral calibration panels on the rover are affected by dust coverage. Data from the shortwave infrared(SWIR) spectrometer onboard the rover are also affected by other environmental factors such as instrumental temperature changes and atmospheric carbon dioxide absorption. This study recalibrated the in situ SWIR data to minimize the impact of the above factors. The recalibrated spectral data show that the reflectance of the landing area falls within the normal range of Martian soil, and confirm the presence of several important absorption peaks. The absorption characteristics indicate the presence of polyhydrated sulfates, gypsum, and hydrated silicates in the surface materials along the rover track, with sulfate content of <27–39 wt.%. Our results further confirm past activity of liquid water in the Zhurong rover landing area, providing mineralogical evidence supporting hypotheses related to underground water or an ancient shoreline.
文摘深空探测巡视任务中巡视器的高精度定位对于巡视器的自身安全与持续运行至关重要。巡视器定位主要包括相对定位和绝对定位两种方式,其中绝对定位方法主要是利用轨道器/着陆器的数据为基准确定巡视器在全局坐标系下的位置。美国Mars 2020任务携带的机智号无人机在火星环境下完成了飞行验证,它能够获得高分辨率的火星表面影像,从而为火星巡视器绝对定位提供了新思路。据此,本文提出了一种卫星-无人机-巡视器影像协同的多分辨率影像匹配绝对定位框架。首先,利用运动恢复结构(structure from motion, SFM)方法对无人机影像进行三维重建,获取局部高分辨率三维地图;然后,开展巡视器影像与无人机影像的多视角匹配,并基于匹配结果利用后方交会实现巡视器在无人机局部地图中的高精度定位;最后,通过局部无人机影像与卫星影像的配准,实现卫星影像全局坐标系下的巡视器绝对定位。为验证本文方法的可行性,开展了巡视器定位仿真试验,试验结果验证了本文方法的可行性,能够为后续我国开展类似工程任务提供参考。
基金supported by the National Natural Science Foundation of China(Nos.41171355and41002120)
文摘A new object-oriented method has been developed for the extraction of Mars rocks from Mars rover data. It is based on a combination of Mars rover imagery and 3D point cloud data. First, Navcam or Pancam images taken by the Mars rovers are segmented into homogeneous objects with a mean-shift algorithm. Then, the objects in the segmented images are classified into small rock candidates, rock shadows, and large objects. Rock shadows and large objects are considered as the regions within which large rocks may exist. In these regions, large rock candidates are extracted through ground-plane fitting with the 3D point cloud data. Small and large rock candidates are combined and postprocessed to obtain the final rock extraction results. The shape properties of the rocks (angularity, circularity, width, height, and width-height ratio) have been calculated for subsequent ~eological studies.
文摘Mars may once have been a wet place where life could flourish,according toNASA scientists who say a robot rover has found evidence that rocks on the RedPlanet“were once soaked with liquid water.” 【原译】据美国宇航局的科学家报道:火星过去可能有丰富的水资源,生物能在那里蓬勃生长。
文摘尽管人类生存的地球麻烦不断,但是人类探索外层空间的努力始终没有松懈。前不久,又一颗“流浪者”挣脱地球之引力飞往火星。就凭这一句(Afternine balloons have deployed,completely enveloping the landing craft,it will bouncealong like a toy on the Martian surface as much as a mile before coming to rest.)便足以让我们展开想象之翅膀!