Complex sentence: At 04:50, personnel aboard the "Petr Velikiy" found two anomalies on the seabed, and at 09:00 the "Rudnitsky" arrived at the location.
Split into simpler sentences: At 04:50, personnel aboard the "Petr Velikiy" found two anomalies on the seabed. At 09:00 the "Rudnitsky" arrived at the location.