Yamgrah

Yamgrah (Pluto) (minor-planet designation: 134340 Pluto) ek bauna grah, Kuiper belt me hae, jon bodies Neptude se duur hae. Ii 9th sab se barraa  aur 10th sab se garrhu (Eris ke baad) chij hae jon Suraj ke sidhe parikrama kare hae.   Duusra Kuiper belt ke chij ke rakam, ii jaada kar ke  ice aur pattharr ke banaa hae, lekin bhittar waala grah se bahut chhotaa hae.  Pluto ke wajan Chandarma ke  one-sixth hae aur volume  one-third hae. Pahile iske ek grah maana jaawat rahaa, lekin ek nawaa definition ke niche iske ek bauna grah classify karaa gais hae. 

Yamgrah ke orbit badalte rahe hae aur ii range kare hae Suraj se  . Suraj ke rosni ke hian talak pahunche me 5.5 ghantaa lage hae jab iske orbital distance  rahe hae. Pluto ke ii orbit ke kaaran kabhi-kabhi Yamgrah Neptune se jaada nagiich hoe jaae hae, lekin ek stable orbital resonance ke kaaran duuno collide nai hoe hae. 

Yamgrah ke paanch chaand ke baare me jaana jaae hae; (moon)|Charon]], the largest, whose diameter is just over half that of Pluto; Styx; Nix; Kerberos; and Hydra. Yamgrah aur Charon ke kabh-kabhi  ek binary system  maana jaae hae, kaaheki duuno ke orbit koi ek me bandha nai hae. New Horizons pahila spacecraft rahaa jon Yamgrah aur uske chaand measurements aur observations lis rahaa jab uu 14 July 2015 me hian se flyby bhais rahaa.

Itihaas
1840s me Urbain Le Verrier, Classical mechanics ke kaam me laae ke Neptune ke predict karis rahaa, Uranus ke orbit ke asar ke analyse kare ke baad. 19th century ke aakhri hissa me astronomer log ii speculate kare lagin ki Neptune ke alaawa ek duusra planet bhi Uranus ke orbit ke asar kare hae. 

1906 me Percival Lowell en 9th grah ke khoj suruu karis jiske uu "Planet X" ke naam diis rahaa aur 1909 me Lowell aur  William H. Pickering ii planet ke coordinate suggest kare rahin. 
Clyde Tombaugh, in Kansas

1929 me Clyde Tombaugh Planet X ke khoj fir se suruu karis. Tambaugh raat ke aasmaan ke dui chaapa utaar ke ii dekhe ke kosis karis ki koi chij aapan position ke badlis hae ki nai. 18 February 1930 me uu ii dekhis ke jon chhaapa ke 23 January aur 29 January ke biich me lewea gis rahaa, me ek chij move hoe hae. Jab aur observation iske confirm karis tab ii sab chaapa ke 13 March 1930 me Harvard College Observatory ke lage bheja gais rahaa. 

Yamgrah ke ek saal, dunia ke 247.94 saal ke baraabar hae, jiske matlab ii hae ki Yamgrag 2178 me iske discovery ke baad pahila orbit complete kari.

Jab Yamgrah ke paae lewa gais rahaa, tab se astronomer log ii nai biswas kare hae ki ii Lowell ke Planet X hae. Pluto ke mass ke anumaan ke 20th century me kamti karaa gais hae. 
+ Pluto ke mass ke estimates Year Mass Estimate by 1915 7 Earths Lowell (prediction for Planet X) 1931 1 Earth Nicholson & Mayall 1948 0.1 (1/10) Earth Kuiper 1976 0.01 (1/100) Earth Cruikshank, Pilcher, & Morrison 1978 0.0015 (1/650) Earth Christy & Harrington 2006 0.00218 (1/459) Earth Buie et al.

References

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