Mock Mars Flight Reveals Big Sleep Concerns for Astronauts

"Doc! You gotta help me! I sleep well enough at night, and mornings aren't bad, but I toss and turn all afternoon!"

That's all?

I am oh so relieved.

Not so fast, Louis. They haven't even left yet.

A similar thing happened on the now-demised Bath Breaking Thread.

The 25 hour day is a well known phenomenon, seen in a number of previous sleep studies where individuals were kept in rooms with no external light cues. From previous things I've read, the conclusion then was that it was a common human trait, and thought to be due to deep programming/instinct/whatever that indicated that the Earth's day had been longer in our species past. That programming being overturned by exposure to daylight.

Of more concern is the person who didn't sleep at all and therefore made multiple errors in his tasks. Those individuals will jeopardise the mission, not those who are out of phase.

Of interest to the wider world is the effect of isolation, lower stimulation and high proportion of time spent in fluorescent light on sleep patterns. Cube dwellers anyone?

A 25-hour sleep cycle would be suited to Martian Sols, then, as a Sol is longer than a Day.

How about the proposed Martian calendar, for further reading?

We were cube farmers, sure, but as with mushrooms they always kept us in the dark and fed us bullshit.

From previous things I've read, the conclusion then was that it was a common human trait, and thought to be due to deep programming/instinct/whatever that indicated that the Earth's day had been longer in our species past.

I thought the day was getting longer due to the earth being slowed down by the tides.

...and the Moon receding....

Approximately 35 years ago, IIRC -

National Geographic had a story of an experiment involving a person or group who were in a cave and had no timepieces to reference. With no time measurement and no Sunlight, the person(s) studied changed the sleep/wake cycle to a very different and much longer period. I believe the subject would stay awake and on task for periods up to three or four days, then sleep a short 8-10 hours, then perhaps only be awake for 12-24 hours and start the long cycle over. I think the experiment was terminated when the wake cycle got so long that the medical directors were concerned about long-term effects. The subject had a very wrong approximation of how long they had been in the cave.

I cannot find, even with Lyn's vast Google help, the article.

I think they were French.....

Just another reason to trash-can the idea of getting to Mars on a least-energy Hohmann orbit. Even a tiny amount of thrust applied*, accelerating the spacecraft to the half-way point and then decelerating the spacecraft the other half the journey, can cut the travel time down to weeks rather than months. It might require a few rendezvous with robotic refueling ships, but the savings in overall spacecraft size, life-support materials and overhead will more than make up for the added costs of the refueling ships. The improved safety for the astronauts is huge.

*It's like compound interest; Even a tiny amount will eventually yield a large return due to the multiplier effect.

Prolly woulda slept better if they'd turned off that simulated security cam.