Why There is Crack in KAABA WALL??

Just want to add something for SMOOTH GUY,there is also a pricking point in my head that where was HAZRAT ABU BAKR AND HAZRAT UMAR at the time of death of HAZRAT MOHAMMAD S.A.W.W?why didnt they attend the NAMAZ-e-JANAZA of HAZRAT MOHAMMAD S.A.W.W?why did the say GHAIBANA NAMAZ-e-JANAZA of HAZRAT MOHAMMAD S.A.W.W on third day after his death?

Was matter of khilafat importand than the death of HAZRAT MOHAMMAD S.A.W.W?if so then why HAZRAT MOHAMMAD S.A.W.W didnt appointed his heir in his life…as you people say so?