If one were to hike during the night and sleep during the day, what differences in navigation would one have to take into account?
In my experience you are more on instruments (such as a compass or GPS) so to speak because of the lower visibility, but are there any other differences?
I think there is a difference to understand, the difference between Navigation and Orientation.
While on a hike, I rely lesser on a compass, but more on landmarks that I am almost certain to see all the while during the hike. For example, a hill. Second thing I rely heavily on is a water stream/river. While heading into a ravine, I am always almost sure of what direction the river should bend next, and what bank I should find myself on.
On night trek/hike, this input/reference is somewhat lost. I think there is more to know than just having an idea of the direction of your destination. While, it is absolutely necessary to know what direction you are supposed to be heading to, its also important to know that the trail may follow a path which turns sometimes in opposite direction before straightening up again. For example, if you are hiking up a ridge, its fairly easy to know that the direction you are heading to is perfect, but while ascending up on hill which has multiple traverses, it sometimes gets a wee-bit confusing if you just pull out your compass and check the direction. The destination might be on north but the trail might head east before turning sharply/bluntly to west so that it heads to direction which was the north from the previous vantage point. So, during the night hike its slightly different if not difficult to keep the orientation right.
I Sometimes track my progress by means of an application. I use apps like MyTracks (Now obsolete), Strava, SportsTracker (So far, my favorite), etc to plot/track the progress, and the application allows me to have a topographical as well as (non-live) satellite view, so I know where I am heading.
I like going the old-school way more often than not (and using the application). Even though this depends a lot on weather and visibility, if I have a clear weather, I usually am right about the trail I am taking, since I almost always have/had been through that trail at least once during the broad daylight. This eliminates the possibility that I might have to climb over something that I shouldn't because if I realize that I am venturing in to some section of trail that I can not recall being onto, I have to retreat than finding a way through that part of the trail. I simply head back for a few minutes to the the place I recall being at when I was here last time around. This eliminates any possibility of trying any stupid climb/descend, helps me to mitigate any risk that the darkness would put me into since I can't see over a much longer distance. e.g. heading to a rock face, or heading to a narrow gorge that I might need to jump over.
I've done a lot of night-walking in a wide range of conditions. I don't think there's any inherent difference between daytime and nighttime navigation - if your daytime skills are solid you shouldn't have any major issues navigating at night.
How good is the visibility?
The real issue isn't daytime or nighttime navigation - it's the quality of the visibility. And there's a lot of overlap between daytime and nighttime.
Not all nights are dark. Under ideal conditions, above the treeline with a clear sky and a good moon, visibility can be almost as good as during the day. You can see paths and distant features, so navigation is relatively unaffected. These conditions can give magical walking.
On dark nights visibility isn't much worse than in daytime with a thick fog or a whiteout. The navigation skills required are pretty much identical. In fact, with a good torch you can often see farther on a dark but clear night than you can on a foggy day.
How good are your skills?
Given that navigation in poor visibility is pretty much the same challenge day or night, the core skills such as attack points, handrails, collecting features, pacing and use of contours are equally applicable. Excluding celestial navigation, which isn't much used in the hills, here's no major skill I'm aware of that's specific to night navigation.
So you simply need solid skills for navigating in poor visibility. Far too many walkers underestimate the skill levels required - I walk in a fog-prone area with notoriously difficult navigation and often have to help parties off the hill. Don't be that person who has to be rescued because you are lost!
If you need to brush up your skills, I strongly recommend Lyle Brotherton's Ultimate Navigation Manual - this is a course used by Special Forces and rescue services around the world, so if you master the book you'll be a navigation ninja.
How good are your tools?
There's a worrying tendency for new walkers to over-rely on GPS. But electronics can fail, so it's absolutely necessary to carry a map and compass and have the old-school skills to use them properly.
That said, in poor conditions you can make your life much easier by carrying a GPS. With good digital mapping and the requisite skills, nighttime navigation becomes relatively trivial.
The final issue is lighting. If navigation might be tricky I carry two torches. The first is a standard flood headlamp to light my footfall and nearby features. But I also carry a state-of-the-art flashlight with a narrow spot beam. This only weighs a few grams and can pick out features at over 200 meters/220 yards. I use it for short periods on max power to look ahead for the path, for trail markers and attack points etc. Few people carry a torch like this, but away from easy trails it comes in very useful.
Take-home message
So in summary, with the right skills and the right tools, nighttime navigation should hold no fears. I love nighttime walking, particularly in the snow. The light, the smells, the sounds - all your senses are heightened and it adds a new dimension to your experience of the hills. So brush up on your skills and get out there!
There are a couple of differences.
Visibility is reduced during the night which makes it harder to see landmarks or where you are in relation to them. This also makes it much harder to measure your progress.
It is much harder to keep track of which direction you are going without a compass or GPS. In the day time the sun provides a good constant reference without much effort. Keeping track of where the north star or southern cross takes some deliberate work and the method for finding north without recognizable constellations needs time and can't be done on the move.
It is much easier to miss a turn or get off a trail. You can even start to wander in circles.
To overcome these difficulties a GPS with a topo map preloaded on the gps can be extremely useful or you can navigate by dead reckoning with a map and compass.
You could only travel short distance at night. You would need a snake stick. The death toll is high for night walkers. Most from snake bite. But even the beach has scorpions at night on it. This is not a advisable thing to do unless above 6,000 feet. Or the snake zone. But then you might take a fall of a cliff. I would avoid such.
