Ọdịdị anyanwụ
Uka unu (M ) bụ otu ọkọlọtọ nke oke na mbara igwe, nhata ihe dịka 2× 10 30 . n'arọ . Ọ bụ ihe nhata na oke ego . A na-egosi ya egosi oke ndị ọzọ, yana ọrịa, nebulae, mkpọ na oghere ojii . Nke a ruru ihe dị ka nonillion ( ọnụ ọgụgụ dị isi ), kilogram abụọ quintillion ( ogologo ọnụ ọgụgụ ), 2000 quettagrams, ma ọ bụ 2 quettakilograms.
. [1] [2]Ebu ụzọ nwe uru nke ndòda mgbe niile site na nha nke Henry Cavendish mere na 1798 nwere nguzozi torsion . [1] Uru ọ dị iche na naanị 1% site na uru nke oge a, mana ọ bụghị nke ziri ezi. [2] A bụ parallax kwa ụbọchị nke malite nke ọma n'oge ngafe nke Venus na 1761 na 1769, [3] na-enye uru nke 9″ (9). arcseconds, ma e jiri ya ike uru dị ugbu a nke 8.794148 ″). Site na uru nke parallax nke ụbọchị ọlụ, mmadụ nwere ike ike ebe dị anya na Sun site na geometry nke m
[3]Atụmatụ mbụ amara nke mbụ bụ Isaac Newton . [1] N'akwa ya Principia (1687), o mere na oke nke ụwa na ihe bụ ihe dịka. . Mgbe e ahụ, ọ bụ na uru ya gbadoro ụkwụ na uru na-akụzi ezi maka parallax, bụ nke o jiworo anya ebe dị anya na ọmụmụ. Ọ gbaziri nha ya na akara nke atọ nke Principia . Uru dị ugbu a maka parallax dị obere ka, na-enye egwu oke nke
- ↑ Barbieri (2007). Fundamentals of astronomy. CRC Press, 132–140. ISBN 978-0-7503-0886-1.
- ↑ How do scientists measure or calculate the weight of a planet? (en). Scientific American. Retrieved on 2020-09-01.
- ↑ Leverington (2003). Babylon to Voyager and beyond: a history of planetary astronomy. Cambridge University Press. ISBN 978-0-521-80840-8.