No. That would be "At the moment he/she/it is eight" which doesn't make any sense - and doesn't use the right conjugation: It probably would be sono otto - the 3rd person plural.
When is it appropriate to put a word like "al" in front of numbers that indicate place? I've seen things like "al quinta", but now in this case it's just "ottavo".
Seems like an idiom. In context searches al [ordinal number] is used in regard to specific things, like al quinto anno which means "IN the fifth year". il quinto anno = "the fifth year". al = *a+il"
The only time I've seen Duo get rid of the article in regard to ordinal numbers is in regard to place or ranking: è quinto = "he is fifth"
There are no hours here, only a race position or pecking order. He is second in charge. ???