Tycho (第谷) | 24 Histories

Overview

The translated histories identify Tycho as an astronomer, scholar, and scientist. This record brings together 9 passages from 2 chapters across 1 history, with names, dates, relationships, offices, and events preserved as source-backed claims.

Names

Type	English	Chinese	Pinyin
Personal	Tycho	第谷	Dìgǔ
Personal name	Tycho	第谷	Dìgǔ
Personal name	Tycho	第谷
Personal name	Tycho Brahe	第谷	Digu

Identity

Historicity: Historical
Identification: Named
Sex: Male

Sex: male
Strongly inferred · qingshigao:028:s0046

Roles

Astronomer
Scholar
Scientist

Life and dates

Attested activity

Source Date: Text: 第谷所定之數 · Western Year: AD 1600
Explicit · qingshigao:028:s0049
Source Date: Text: 西人第谷以前 · Western Interval: Start: AD 1572 · End: AD 1601
Explicit · qingshigao:028:s0046, qingshigao:028:s0047
Source Date: Text: 迨至第谷 · Western Year: AD 1600
Explicit · qingshigao:028:s0047
Source Date: Text: 雍正癸卯 · Western Year: AD 1723
Explicit event contextual date · qingshigao:050:s0003, qingshigao:050:s0007

Origins and identity

Ethnicity: Westerner / 西人
Explicit · qingshigao:028:s0046
Label: Western / 西人
Explicit · qingshigao:050:s0007

Career and standing

Label: astronomer / 天文學者
Explicit · qingshigao:050:s0007

Events and relationships

Kind: scientific · Role: discoverer · Action: explained-atmospheric-refraction
Explicit · qingshigao:050:s0015, qingshigao:050:s0016, qingshigao:050:s0017, qingshigao:050:s0018
Kind: scholarly · Role: astronomer · Action: fixed-precession-rate · Outcome: 51 seconds eastward per year (~1° in 70 years) / 每歲東行五十一秒，約七十年有餘而行一度
Explicit · qingshigao:028:s0047
Kind: scientific · Role: observer · Action: fixed-tropical-year-length · Statement: Set tropical year three parts in ten thousand below Guo Shoujing
Explicit · qingshigao:050:s0007
Kind: scientific · Role: authority · Action: supplied-mars-sun-distance-ratio · Other Person Id: Copernicus (歌白尼)
Explicit · qingshigao:050:s0029
Relation: precession-rate-close-to · Person Id: Guo Shoujing (郭守敬)
Explicit · qingshigao:028:s0047

Assessments and attributes

Assessment: rate-not-immutable · Provenance: Mode: historian-judgment
Explicit · qingshigao:028:s0049

References in the histories

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

Draft History of Qing, Chapter 28Volume 28 Treatises 3: Astronomy 3, Sun, Moon, and the Five Planets, Fixed Stars, Yellow and Red Paths, the Twelve Stations, and Lunar Lodges, Hun Dan Zhong Xing · 3 passages

Open chapter

新法算書載西人第谷以前，或云恆星百年而東行一度，或云七十餘年而東行一度，或云六十餘年而東行一度，隨時修改，訖無定數，與古人屢改歲差相同。 Before Tycho, Westerners guessed precession at one degree per century, per seventy-odd years, or per sixty-odd—each revision unsettled, mirroring China's shifting precession rates.

迨至第谷，方定恆星每歲東行五十一秒，約七十年有餘而行一度，而元郭守敬所定歲差之數亦為近之。 Tycho fixed annual eastward motion at 51 seconds—about one degree in seventy years—close to Guo Shoujing's Yuan rate.

然則第谷所定之數，亦未可泥為定率，惟隨時測驗，依天行以推其數可也。」 Tycho's rate should not be treated as eternal; periodic measurement must track heaven's actual motion."

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

Open chapter

西人第谷所定，減郭守敬萬分之三。 Tycho Brahe set a value three parts in ten thousand below Guo Shoujing's.

至奈端等屢加測驗，謂第谷所減太過，定為三百六十五日二四二三三四四二０一四一五，比第谷所定多萬分之一有奇。 Newton and his successors, after repeated observation, judged Tycho's reduction excessive and fixed the year at 365.242344201415 days — slightly more than one part in ten thousand above Tycho's value.

以除周天三百六十度，得每日平行，比第谷所定少五纖有奇。 Dividing this into the 360° circuit of heaven yields a daily mean solar motion slightly more than five fibres less than Tycho's.

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.

西人第谷悟得蒙氣繞地球之周，日月星照蒙氣之外，人在地面為蒙氣所映，必能視之使高。 Tycho Brahe grasped that the atmosphere encircles the Earth: the luminaries shine beyond it, while an observer on the ground, sighting through the air, necessarily sees them displaced upward.

又據歌白尼、第谷測得火星距地與太陽距地之比，如一百與二百六十六，用轉比例法，求得太陽在中距時地平上最大地半徑差一十秒，其逐度之差，以半徑與正弦為比例。 From Copernicus and Tycho's ratio of Mars's distance to the Sun's (100:266), they derived the Sun's maximum horizon parallax at mean distance as 10″, with degree-by-degree values proportional to radius and sine.