Cassini (噶西尼) | 24 Histories

Overview

The translated histories identify Cassini as an astronomer, mathematician, scholar, and scientist. This record brings together 11 passages from 1 chapter across 1 history, with names, dates, relationships, offices, and events preserved as source-backed claims.

Names

Type	English	Chinese	Pinyin
Personal	Cassini	噶西尼	Gaxini
Personal name	Cassini	噶西尼	Gaxini

Identity

Historicity: Historical
Identification: Named
Sex: Uncertain

Roles

Astronomer
Mathematician
Scholar
Scientist

Life and dates

Attested activity

Source Date: Text: 康熙十一年 · Western Year: AD 1672
Explicit · qingshigao:050:s0027
Source Date: Text: 雍正癸卯 · Western Year: AD 1723
Explicit event contextual date · qingshigao:050:s0003, qingshigao:050:s0012

Origins and identity

Label: Western / 西人
Explicit · qingshigao:050:s0012

Career and standing

Label: astronomer / 西人
Explicit · qingshigao:050:s0012, qingshigao:050:s0019

Places and affiliations

Place: France / 富郎濟亞國 · Relation: observed-at
Explicit · qingshigao:050:s0027
Place: latitude 44° north / 北極出地高四十四度處 · Relation: observed-at
Explicit · qingshigao:050:s0022

Learning and skills

Skill: astronomical measurement / 測驗 · Level: renowned
Explicit · qingshigao:050:s0019, qingshigao:050:s0027

Events and relationships

Kind: scientific · Role: investigator · Action: derived-mars-and-solar-parallax · Other Person Id: Richer (利實爾)
Explicit · qingshigao:050:s0028, qingshigao:050:s0029, qingshigao:050:s0030
Kind: scientific · Role: investigator · Action: derived-refraction-formula
Explicit · qingshigao:050:s0019, qingshigao:050:s0020, qingshigao:050:s0021, qingshigao:050:s0022, qingshigao:050:s0023
Kind: scientific · Role: investigator · Action: established-angle-area-methods
Explicit · qingshigao:050:s0038
Kind: scientific · Role: observer · Action: measured-annual-perigee-motion
Explicit · qingshigao:050:s0042
Kind: scientific · Role: observer · Action: measured-lunar-inequalities
Explicit · qingshigao:050:s0089, qingshigao:050:s0096, qingshigao:050:s0103, qingshigao:050:s0107
Kind: scientific · Role: observer · Action: measured-mars-zenith-distance · Other Person Id: Richer (利實爾) · Place: France / 富郎濟亞國
Explicit · qingshigao:050:s0027
Kind: scientific · Role: investigator · Action: measured-node-angle-limits · Other Person Id: Newton (奈端)
Explicit · qingshigao:050:s0121
Kind: scientific · Role: observer · Action: measured-obliquity · Other Person Id: Riccioli (利酌理)
Explicit · qingshigao:050:s0012
Kind: scientific · Role: authority · Action: supplied-solstice-constants · Date Context: Source Date: Text: 雍正癸卯 · Western Year: AD 1723
Explicit · qingshigao:050:s0045
Relation: collaborated-with · Person Id: Richer (利實爾)
Explicit · qingshigao:050:s0027

References in the histories

Open any source group to read the Chinese and English passage in context.

Draft History of Qing, Chapter 50Volume 50 Treatises 25: Calendar 6 · 11 passages

Open chapter

黃赤大距，古闊而今狹，恆有減而無增，西人利酌理、噶西尼測定黃赤大距二十三度二十九分，比第谷所定少二分三十秒，比刻白爾所定少一分。 The obliquity of the ecliptic was greater in antiquity and has steadily narrowed; Riccioli and Cassini measured it at 23°29′ — 2′30″ below Tycho and 1′ below Kepler.

噶西尼反覆精求，謂視線光線所歧雖有不同，相合則有定處。 Cassini, after painstaking inquiry, showed that however much the sight line and light ray diverge, their point of convergence is fixed.

康熙十一年壬子秒分前十四日夜半，火星與太陽沖，西人噶西尼於富郎濟亞國測得火星距天頂五十九度四十分一十五秒，利實爾於同一子午線之噶耶那島測得火星距天頂一十五度四十七分五秒，同時用有千里鏡能測秒微之儀器，與子午線上最近一恆星，測其相距。 On the night fourteen days before the Kangxi 11 renzi epoch mark, at Mars's opposition, Cassini in France measured Mars at 59°40′15″ from the zenith while Richer on Cayenne, on the same meridian, found 15°47′5″; both used telescopic instruments precise to the second and measured each planet's distance from the nearest meridian star.

噶西尼所得火星較低一十五秒，因恆星無地半徑差以之立法，用平三角形，推得火星在地平上最大地半徑差二十五秒，小餘三七。 Cassini's Mars appeared 15″ lower; since fixed stars show no parallax, they used plane triangles to derive Mars's maximum horizon parallax as 25.37″.

噶西尼等乃立角積相求諸法，驗諸實測，斯為菂合。 Cassini and his colleagues devised methods relating angle and area that matched observation exactly.

西人噶西尼等測得每歲平行一分二秒五十九微五十一纖零八忽，比甲子元法多一秒四十九微有奇。 Cassini measured the annual advance of perigee at 1′2″59.51‴08, slightly more than 1″49‴ above the jiazi epoch system.

用西人噶西尼所定，推得雍正癸卯年天正冬至為丙申日丑正三刻十一分有奇，比甲子元法遲二刻。 From Cassini's constants, the winter solstice of Yongzheng guimao falls on day bingshen at the third quarter of the chou watch — about two quarters later than the jiazi epoch system.

西人噶西尼以來，屢加測驗，定日在最高朔望前後四十五度，最大差為三十三分一十四秒； Cassini's observations fix the maximum second inequality at 33′14″ when the Sun is at apogee and 45° from syzygy;

西人噶西尼以來，取月距日與月高距日高共為九十度時測之，除末均之差外，其差與月距日或月高距日高之獨為九十度者等。 Cassini found that when the sum of the Moon's elongation and the separation of their apogees equals 90°, the correction—aside from the final inequality—equals that when either alone is 90°.

西人噶西尼以來，測日月最高同度或日月同度兩者只有一相距之差，則止有三均。 Cassini found that when the solar and lunar apogees coincide, or when the Sun and Moon share the same longitude with only one separation variable, three inequalities suffice.

西人奈端、噶西尼以來，測得日在兩交時，交角最大為五度一十七分二十秒； Newton and Cassini measured the maximum node angle at 5°17′20″ when the Sun is at the nodes;