The Workings Of 'Between'

What we know so far about Between is that it appears to be a separate dimension from the one that Pern exists in, or really, a gap between dimensions. This gap is not governed by the usual laws of time and space, meaning that one can enter it from any location, and wind up anywhere else in a different time and place. In one aspect, however, it complies with time and space - the further away the time or place, the longer it takes to get there. It could be said that Between is like a long hallway full of doors, and the further away the destination, the further down the hall it is.

This could be used to explain the odd experiences in "Dragonsblood", where Lorana, a girl with the ability to hear all dragons, actually attempts to contact dragons between, and inadvertently ends up conversing with Wind Blossom, over a distance of many years. It appears as though Lorana managed to speak with Wind Blossom as a result of the dragon in Between acting as a sort of amplifier for her thoughts. It would have been a sheer coincidence that she managed to reach such a location, without being between herself.
This suggests that Lorana, while not able to go Between physically, may be able to hear Between, through a process not completely clear. Alternatively, Lorana may have made contact in the brief millisecond where the dragon would have been halfway between Pern and Between, and subconsciously processed the thoughts of Wind Blossom in a much shorter period of time than the conversation took.
It has been said in the past that the ability to hear all dragons is limited to women, being connected to the "X" chromosome. In Lorana's case, it is likely that the area of the chromosome that enables such a thing to occur has undergone a mutation of sorts, increasing the ability to the point. It could be said that this ability is linked to all Queen riders, but I doubt this, as its use would likely have been better documented. And, as shown with the white dragon Ruth, every now and then somebody will be born with unique abilities that will not be repeated.

The main focus of this article is to discuss what happens to dragons and riders who stay Between. A short story, "Beyond Between", attempts to address the matter, unfortunately it raises as many questions as it answers.
Taking place immediately after Moreta's fateful ride, Moreta and Holth find themselves trapped Between in a realm of cloudy grey smoke. Eventually found by Marco Galliani & Duluth, an early rider and dragon from the First Fall who went Between accidentally, they are guided to Paradise River, where Marco regularly leads dragons lost Between. Moreta later returns to Waterhole Hold, where she went last Between, and attempts to get the holder to notice her, ultimately succeeding in getting word to Benden Weyr. Leri and Orlith travel to Waterhole Hold, where they reunite with Moreta and Holth, before going Between together.

The whole thing is fairly simple - Moreta, Holth, Marco and Duluth are all ghosts, and have a small degree of physicality left, each being able to interact with their surroundings to some degree; in one odd case, a ghostly dragon being able to lift its living rider, although this could be chalked up to the telekinesis of the dragons mentioned in "The Skies Of Pern". This also raises the question of whether or not an ex-rider, such as Lytol, travelling to Paradise River, would be able to sense their dragon.
Dragons are also able to travel out of Between after dying there, but they are only able to travel to the place they initially came from. However, they are able to follow the images from other dragons, and travel to their last point of entry. It also mentions the concept of a place "Beyond" Between, quite likely an afterlife of sorts.  

The important question thus becomes, "if a dragon goes between without his rider, how are they reunited?" One thing that can be immediately discerned is that all the dragons and riders who were separated in some way have certainly reunited after death, for the reasons mentioned below. To understand how this could work, think of the film "Casper". One of the major elements of the film is that ghosts don't cross over until their unfinished business on earth is finished. In the same way, the dragons' unfinished business is their rider.

I cannot go anywhere. There was just the slightest emphasis on 'go'.
'What do you mean, you can't "go"?' Moreta cried out loud.
Not yet, and not with you, was Holth's cryptic reply.
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Holth cannot go beyond yet because Leri is still alive, and Moreta must also wait for Orlith. If Holth had thought that she had no chance of being reunited with Leri, she would have gone Beyond in seconds. Holth would be no different from the countless other dragons over the centuries who went Between without their riders. If they thought similarly, then there would be a large amount of deceased dragons at Paradise River, as Marco would have found them at some point.
How do humans get Between then? Simple, they don't. Once a dragon remains Between, it dies. The grey smoky Between is merely how such a realm appears from the view of the deceased. Once the dragon returns to Pern, it occupies a different level of existence, appearing to the living as a ghost. When a person dies on Pern, they occupy this same level of existence. It is not known how the dragon and rider find each other, but it seems likely that their connection would be restored once both were on the same level, and thus the dragon could reach the rider via imaging, but it could also be that, like in "Casper", both, upon restoring their connections, go Beyond from there, in the similar way to the whole "tunnel of light".

He took another breath and said in a rush, 'Sometimes though…I see dragons, usually with their riders, just heading away-sometimes heading up…' He waved his hand in some inexplicit overhead direction. 'They aren't heading for between, because they are already between. They are aiming for some destination…beyond between.
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In other words, some dragons have gone beyond between without their riders. The most likely answer to this is that once both dragon and rider are between, they go beyond between, although not necessarily together. If injured during threadfall, or if suiciding together, dragon and rider will go beyond between instantly. If the rider dies, the dragon will follow, and then both will go beyond between from there. If the dragon dies before its rider, it will wait for its rider to die, and once it senses the mind of its rider, both will go beyond between.

The result of all this is a reassuring one. No matter how far apart a dragon and rider are at their deaths, be it in another area of the planet or even in a different time, nothing will stop them from being reunited Beyond.