Just as the spaceship was traveling faster than light, you are traveling faster than snail-mail, so you beat some (or all) of your mailed selfies home. The day after your homecoming, the mail carrier delivers two of your pictures: one from the trip out, and a second from your trip back.
Ongoing research has shown that oral melatonin supplements can promote the dipping process. They can reduce nocturnal systolic blood pressure by about 6 mm/Hg, and diastolic pressure by 4 mm/Hg. Not surprisingly, the studies also indicate that melatonin improves sleep quality, which allows the body to relax more.
How Stress Affects Blood Pressure. This physical reaction to stress is what causes an increase in blood pressure. However, this reaction is only temporary and will end once the stress goes away.