A homesick astronaut on Mars Scientific American

There are going to be plenty of technological and physiological hurdles to jump before we land the first astronauts on Mars. But once they’re safely on their journey, another kind of challenge may rear it’s head. What happens when you can no longer see Earth?
Even the quickest Mars trip is going to be long. If you get the timing right, as Dennis Tito plans to, you could manage a round trip to Mars in 501 days. Most missions, especially if they land on the surface and do a bit of exploring, will take longer.