My son was at the gym in our complex. He came running into the house and said he and his friend just saw this massive round ship with lights pulsating from the side. I asked him seriously and went onto the deck immediately. Lo and behold, this massive round shaped UFO with side pulsating white lights were moving towards Pretoria. It could not have been an aeroplane or helicopter, it was silent. It disappeared over the Magalies Mountains going SW towards Pretoria and pelindaba. This is our second sighting in about six months. We do live close to Pelindaba, South Africa’s main nuclear research center.