跳到主要內容

窥幾

kknews:


測量： 星過中天 meridian transit . Ulugh beg的地下天文台同功能。


窺幾之制，長六尺，廣二尺，高倍之。下為趺，廣三寸，厚二寸，上跂廣四寸，厚如趺。以板為面，厚及寸，四隅為足，撐以斜木，務取正方。面中開明竅，長四尺，廣二寸。近竅兩旁一寸分畫為尺，內三寸刻為細分，下應圭面。几面上至梁心二十六尺，取以為準。窺限各各長二尺四寸，廣二寸，脊厚五分，兩刃斜閷，取其於幾面相符，着限兩端，厚廣各存二寸，銜入幾跂。俟星月正中，從幾下仰望，視表梁南北以為識，折取分寸中數，用為直景。又於遠方同日窺測取景數，以推星月高下也。

可視為現代重要光學測量optical astrometry 儀器eg carlsberg meridian telescope 的雛形。可惜當年還沒有改良發展下去。




Reference :

Baidu

Carlsberg meridian telescope wiki

Meridian circle 

Ulugh beg observatory 

標籤：

留言

張貼留言

這個網誌中的熱門文章

ES8311 and ES8388 codec IC

ES8388 audio codec module is one of the audio codec modules available that is supported by ESP32 and official ESP-ADF releases. The ES8388 module lets you have: Stereo microphone and line input Stereo headphone and line out Up to 96 kHz 24 bpp high quality audio This module is compatible with all MCUs that have I2C and I2S ports (like ESP32, ESP8266, STM32, i.MX6, Raspberry Pi, etc) ES8311 Maxgerhardt github PCBartist twblogs ESP32-A1S  (limited stock)Audio codec AC101 or ES8388 built-in. NB the pinouts and firmware are different! Arduino - ESP31-A1S instructable Phil Schatzmann and his github   Simple A2DP thaaraak github on ESP32-A1S github of Yveaux and  Marcel-licence ESP ADF   example:  Logitech PiCorePlayer squeeze lite squeezebox forum   ESP32-Audio-kit  (from AI thinker) based on ESP32-A1S, is simple and small. But upgrade-ability seems limited  Alex John Talbert mixer equalizer: can this be used as simple equalizer? how about proces...
張貼留言
閱讀完整內容

sharpstar 150mm f/2.8 hyperbolic astrograph

to be launched in summer, 2019. spot diagram is now available, and connections diagram to camera is shown . list price RMB 13,000 ( USD 1900 approx) comparing this with Takahashi epsilon-180ED: spot diagram: connections: the focuser is 2.5 inch, and threads are M48 x 0.75mm   cloudynights first impression threads   some nice photo review from skypoint   Astrofotoblog review  c
2 則留言
閱讀完整內容

越南香草

Ngo ~ "N-gaw" Mui ~ "Moo-ee" Ngo ~ "N-gaw" Mui ~ "Moo-ee" Ngo ~ "N-gaw" Mui ~ "Moo-ee" Ngo (N-gaw) ,  Mui  (Moo-ee )  Cilantro Coriandrum sativum, chinese parsley  Ngo Gai (N-gaw guy), Mui Tau (Moo-ee Tao), Ngo Tau (N-gaw Tao)   Mexican Coriander,  Sawtooth Coriander, Cilantro Eryngium foetidum 　　 娥女帝(拼音), 刺芹 　　特徵：娥女帝是短株形的植物，氣味清淡，葉邊呈鋸齒形，十分容易辨認。來源地：越南。 功效：和白夏差不多，娥女帝亦有祛濕、解毒及驅風的療效。建議食法： Pho,  (Bánh Xeò) 越南煎餅, 炒菜,湯,咖哩 Ngo Gai ~ "N-gaw guy" Mui Tau ~ "Moo-ee Tao" Ngo Tau ~ "N-gaw Tao" - See more at: http://vietworldkitchen.typepad.com/blog/vietnamese-herb-primer.html#sthash.I9rzkzwI.dpuf Rau Ram (Rau Rahm) Vietnam Coriander, Laksa Leaf, "Vietnamese mint(actually not a mint)". Polygonum leaf Polygonum odoratum Peppery, quite spicy. In salad, soup Hung (Hoong), , Hung Lang (Hoong Lang) Spearmint.  Vietnamese coriander Hung Lui (Hoong Lou-ee), Hung ...
張貼留言
閱讀完整內容