Original: It was given the temporary designation S/1989 N 4discovery IAUC circular The discovery was announced (IAUC 4824) on August 2, 1989, but the text only talks of "10 frames taken over 5 days", giving a discovery date of sometime before July 28.
Simplified: The discovery was said (IAUC 4824) on August 2, 1989, but the text only talks of "10 frames taken over 5 days", giving a discovery date of sometime before July 28.