Interesting, in light of my recent post about homesickness, that I just read this article by Joe Palca today (published yesterday on NPR) about the frequent perception that the ride home from a trip is shorter than the trip to the destination, even if they take the same amount of time.

In 1969, astronaut Alan Bean went to the moon as the lunar module pilot on Apollo 12. Although the trip going to the moon covered the same distance as the trip back, “returning from the moon seemed much shorter,” Bean says.

People will often feel a return trip took less time than the same outbound journey, even though it didn’t. In the case of Apollo 12, the trip back from the moon really did take somewhat less time. But the point remains that this so-called “return trip effect” is a very real psychological phenomenon, and now a new scientific study provides an explanation.

Niels van de Ven, a psychologist at Tilburg University in the Netherlands, says the conventional wisdom is the trip back seems shorter because it’s more familiar, so people recognize landmarks. “And that might help to increase the feeling of speed, of how fast you travel,” he says.

But that didn’t seem right to him. “When I take, for example, an airplane, I also have this feeling, and I don’t recognize anything on my way, of course. When I look out of the window, I don’t see something I recognize,” van de Ven says.

Van de Ven’s project is then described. His results indicate that there is something psychological going on, since there is a perceived difference even when the time is unique. You can read the whole piece here, but you might not want to. As Palca concludes:

It’s true that the return home effect is just an illusion, and a better understanding of it might make it go away. But van de Ven says that might not be a good idea.

“In the end, this return trip effect gives you a positive feeling once you get home, so I’m not sure whether you want it to go away.”