Julia's Laughing Mad reaction after awakening. Read "The Woobie" section of the film's YMMV for the full details.
Just before releasing the sleep capsule where the rest of the crew of the Odyssey still sleep so they can get to safety the original Jack lingered a bit in front of Julia's capsule. Based on his expression he probably realizing that there was a big chance that he might not return alive and this might be the last time he would see his wife.