The solar mass (Mâ) is a standard unit of mass in astronomy that is used to indicate the masses of other stars, as well as clusters, nebulae and galaxies. It is equal to the mass of the Sun, about two nonillion kilograms :
The semicolon or semi-colon (;) is a punctuation mark that separates major sentence elements. A semicolon can be used between two closely related independent clauses, provided they are not already joined by a coordinating conjunction. Semicolons can also be used in place of commas to separate items in a list, particularly when the elements of that list contain commas.
Colons (:) are used in sentences to introduce that something follows like a quotation, example or a list. Semicolons (;) are used to join two independent clauses, to separate main clauses joined by a conjunctive adverb or to separate items in a list that already uses commas. Still confused?