天問一號拍攝的高清火星影像

彩色中分辨率 (700x 525 pixels), @~5000km

單色, 高分辨率 ( 600 x 776 pixels)

單色, 高分辨率 ( 626 x 700 pixels)

images taken by its Mars orbiter Tianwen-1 of its planned rover landing site:

110.318 degrees east longitude and 24.748 degrees north latitude, within the southern portion of Utopia Planitia

from wikipedia:

中解像度相機（MRC），在400 km的軌道上解像度為100 m
高解像度相機（HRC），在400 km軌道上的解像度為2 m

全色图像由高分辨率相机在距离火星表面约330千米-350千米高度拍摄，分辨率(GSD)约0.7米，成像区域内火星表面小型环形坑、山脊、沙丘等地貌清晰可见。据测算，图中最大撞击坑的直径约620米(~160 pixels)。彩色图像由中分辨率相机拍摄，画面为火星北极区域。

estimate external dimensions: 0.5m(w) x 0.7m(h) x 1m(d)

dawes' limit

assume aperture is 390 mm

解像度 (arcsec)=116/口徑 (mm) = 0.297 arcsec

hi res cam:

deduced from CNSA news: picture size is 3km over 330 km (cropped?), 0.7 m resolution

or fov equivalent to 30 arsec

该高分相机采用了集光能力强、有效口径利用充分、光学传递函数高、杂光抑制能力强的长焦距大视场离轴光学系统，以全碳化设计理念解决了相机长焦距技术指标与重量资源紧张之间的矛盾，通过碳纤桁架实现了光学元件的位置保证和高轻量化的结构设计。相机配置了五谱段TDICCD (time delay integration)和国产自主研发的CMOS两种成像探测器，实现线阵推扫(line scan)和面阵(matrix)成像的兼容，有望获得火星表面真彩色融合图像及视频图像。

deduced from above data:

The TDI CCD is 6144 pixels, but the height is likely to be 1338 pixels

pixel size is 8.75 um

focal length: f/12

TDI CCD sensor size: 53.76 x 11.71 mm?

from GSD calculator tool, the above deduction is pretty close

“天问一号”高分辨率相机采用了集光能力强、有效口径利用充分、光学传递函数高、杂光抑制能力强的长焦距离轴三反消像散光学系统(Cook TMA)，焦距4640mm，全视场角2°×0.7°。光学系统采用了先进的低敏感度设计方法，应用高陡度大偏离量离轴高次非球面反射镜，同时保证了系统像差校正与大摄远比的实现。光机结构以全碳化设计理念，解决了相机长焦距技术指标与重量资源紧张之间的矛盾，通过碳纤维桁架实现了光学元件的高精度位置保证和高轻量化的结构设计，相机总质量不到43公斤。相机焦面配置了3片包含全色、红、绿、蓝、近红外的五谱段TDI CCD图像传感器和2片国产面阵全色CMOS图像传感器，可以实现多光谱线阵推扫成像和全色面阵成像的兼容，具备获得火星表面高分辨率全色图像、彩色融合图像与视频图像的能力。

29/6/2022:

據國家航天局消息，截至周三（6月29日），「天問一號」任務環繞器和火星車均完成既定科學探測任務，經正常飛行706天，任務環繞器獲取了覆蓋火星全球的中分辨率影像數據，各科學載荷均實現火星全球探測。

此外，當局公布天問一號近期拍攝的火星影像，這些影像包括環繞器中分相機拍攝的阿斯克拉山影像，直徑456km，高18km，顯示了阿斯克拉山頂的火山口特徵，存在多個火山口坍塌事件；南極冰蓋影像，展示了火星南極極冠，研究認為火星兩極長期和永久性的極冠主要由乾冰（固態二氧化碳）和水冰構成；水手大峽谷西部地貌影像，其東西延伸超過4000km，南北寬150至700km，最深可達7km；阿拉伯高地撞擊坑影像，展示了該地區分佈的數十個撞擊坑的地貌特徵；

蒙德環形坑邊緣影像，空間分辨率約0.5m，該環形坑直徑約91km，展示了蒙德環形坑坑緣的地貌特徵，以及環形坑內部，坑緣可見明顯向坑內坍塌的現象。

just for comparison:

kennen kh-11

2.4m mirror

s0.65m over 250 km

0.05 arcsec

Jiang Bing 9 constellation satellites.

Chinanews

speakout

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Scythians 斯泰基塞種西古提人

900 BC - 200 AD British museum Tomb of scythe prince, Buktarma valley, 1200 masl, Google map Herodotus 絲路上的帝國 Biblegeography 哥羅西書 3：11 在此並不分希利尼人、猶太人、受割禮的、未受割禮的、化外人、西古提人、為奴的、自主的．惟有基督是包括一切、又住在各人之內。塞種塞迦 saka 史記漢書西域傳：塞種 ctext 昔匈奴破大月氏，大月氏西君大夏，而塞王南君罽賓。塞種分散，往往為數國。自疏勒以西北，休循、捐毒之屬，皆故塞種也。匈奴列傳 Ctext ：塞王《史記》在《大宛列傳》與《匈奴列傳》中，詳細記錄了中亞至天山一帶的塞種（塞王、塞地）狀況。例如，文中記載了月氏西破走塞王，導致塞人南遷越過懸度（今帕米爾高原及克什米爾一帶） Baike Genetic history Genetics Nih griffin ? Scytho-Siberian world 塞迦 saka wiki Disappeared? Sarmatians （薩爾馬泰，奄蔡史記 , Aorsi ）and goths YouTube

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