celebrate/mark one's birthday?

[maoyueh]

Are "celebrate" and "mark" interchangeable in the following contexts? What is the difference between the following two sentences? Thank you.

A. He is going to celebrate his 70th birthday next week.
B. He is going to mark his 70th birthday next week.

[emsr2d2]

Are "celebrate" and "mark" interchangeable in the following contexts? What is the difference between the following two sentences? Thank you.

A. He is going to celebrate his 70th birthday next week.
B. He is going to mark his 70th birthday next week.

"To celebrate" particularly suggests a party or a gathering or at least an event of some kind.
"To mark" simply means to do something to show recognition of his birthday.

However, "He is going to celebrate his..." is sometimes used simply to mean "It will be his birthday..."