is there a different edition of it?
Yes, there exists different editions like the ones by Friedrich Chrysander and Max Seiffert , Mozart, Goossens and Andrew Davis and others.
Messiah (Handel)
The edition edited by Friedrich Chrysander and Max Seiffert for the Deutsche Händel-Gesellschaft (Berlin, 1902) is not a general performing edition, but has been used as a basis of scholarship and research.

In addition to Mozart's well-known reorchestration, arrangements for larger orchestral forces exist by Goossens and Andrew Davis; 
the most famous oratorio in the world is messiah written by Composed by George Frideric Handel,with a scriptural text compiled by Charles Jennens. when was this composed? 1741. how many parts are there in this? Three.
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Messiah (Handel) [SEP] Editions
The first published score of 1767, together with Handel's documented adaptations and recompositions of various movements, has been the basis for many performing versions since the composer's lifetime. Modern performances which seek authenticity tend to be based on one of three 20th-century performing editions. These all use different methods of numbering movements: The edition edited by Friedrich Chrysander and Max Seiffert for the Deutsche Händel-Gesellschaft (Berlin, 1902) is not a general performing edition, but has been used as a basis of scholarship and research. In addition to Mozart's well-known reorchestration, arrangements for larger orchestral forces exist by Goossens and Andrew Davis; both have been recorded at least once, on the RCA and Chandos labels respectively.