Distance
"A better way to indicate apparent size would be to say "it was three degrees across", or "the size of my clenched fist at arm's length".
A proper description would relate something like "it traveled from zenith to horizon in less than 5 seconds"
Seems to me angular measurements are just as "useless" without knowing the distance to the object.
A firefly can travel from the zenith to the horizon in 5 seconds- if it's in your back yard.