Scarlett Johansson didn’t seem to be mourning her split with Sean Penn during a late night out with Justin Timberlake. The pair headed to Kenmare and partied until 3:30 a.m. yesterday along with Bungalow 8 nightlife queen Amy Sacco and a few other friends. While Johansson and Timberlake — who split with Jessica Biel in March — have been linked in the past, a spy said, “It didn’t look particularly flirty. Scarlett was dressed down and remained low-key with Justin and the group. At one point she went over to the deejay to request a song. Later, two girls joined them. They all left together around 3:30.”