At the invitation of Namcha (), several players gathered on the evening of 13 August 2021 at the Thesos Research Centre to learn more about Atys and its sky.

    In game, the compass tells you how far your character is from a creature or character you are targeting. It also tells you the distance to any place of Atys when, on the map displayed (key M), you click on the flag that indicates the place in question. But in this case, the distance is wrong. Indeed, for long distances (greater than the maximum distance for direct targeting), the compass is not realistic: the New Lands are a bit larger than they seem!

    The real distance, between two cities for example, must in fact be calculated from the Atysian time taken by your character to actually cover it in a straight line, which can be calculated from the clock displayed on the map. However, multiplying the distance indicated by the compass by 20 is a good approximation of this real distance within each country (country = area delimited by vortices), but not between countries.

    This being said, the New Lands cover an area of about 120,000 km² (a square of 300 to 350 km on each side), which is still quite small, much smaller than the Old Lands in any case. Let's remember that what we call New Lands is the set of countries mapped by the in-game maps, countries that the homins have joined after the Great Swarming. In fact, since the beginning of the game, the homins live on these New Lands and only know about the Old Lands, which are not mapped, what the texts say of them.

    But let's go back to the question of using the compass to evaluate the distance between countries. Indeed, with the compass you can play the funny game of triangulating positions to obtain a "server map" which is very different from the map displayed in game. The fact remains that it is the latter that is the authentic one for the story: the "server map" is just computer science. Or if it had a meaning, it has long since been lost by the developers who succeeded one another on Ryzom.

    If the sky is not at all coherent in game, the celestial objects that we see there do exist in history. There are four of them and, since night has just fallen, I will review them before describing their interactions.

― Let's look to the east. A nebula is rising there, it will soon be at its zenith. This celestial body is the star of the Atysian system, its center. It is a sun then, but which radiates very little in the visible spectrum. Moreover, it is veiled by a cloud of celestial dust.

― To the north, we have a magnificent planet with a ring. It is a gas giant, it revolves around the star (normally). And Atys is a satellite of this gas giant that the gaming community has named Sagaritis.

― To the southwest, we see a “red moon”. It is moving southwards (I remind you that the movements in game are completely wrong). It orbits Sagaritis, like Atys, but with a more elliptical orbit. It is always full and it emits its own light, weak.

― Last of the list of four, the one that does not move, in the east. It is the only star that is "correct" in game: indeed, it should not move.It is the star that makes the day, the luminary. It is a satellite of Atys, geostationary. And, as scholars know, in the Ancient Lands, this star is at the zenith, upright.

    Atys, I said, is a satellite of Sagaritis, the gas giant planet with its ring. Atys always presents the same face to Sagaritis (it is called "synchronous rotation", like that of the Moon around the Earth). It goes around Sagaritis in one cycle, the Atysian cycle.

    When the game was designed, the celestial bodies did not have names. You could almost say that they were there just to look pretty. As I said, the community named the gas giant Sagaritis (mnemonic: SAGA of RYzom, aTYS). This name, since "officially" adopted, refers to an Earth legend, of the Phrygian people (antique occupant of the present Turkey). Sagaritis is mentioned in the chronicle titled Chrysalis, which tells of the escape of Yrkanis from Jino. It was also mentioned by the player Dalcini in one of his poems. Both texts refer to the Terran legend, with nuances. That's why, to stay in this legendary reference, I propose the name of Cybele, or Cybel (masculine or feminine, you decide, both are acceptable) for the nebula. The legend says, roughly, that Atys is son of Cybele, and Sagaritis his lover (in Chrysalis, the genders are reversed), which carries a secret meaning for the story of the game.

    And what makes the seasons on Atys, it is indeed the nebula, or Cybele. In fact Atys goes around Sagaritis, and Sagaritis goes around Cybele. For half a cycle, one should not see Cybele. When she rises, spring begins. Most of Cybele's radiation is not in the visible spectrum, but it contains enough energy to create, in addition to the luminary's, the seasons on Atys.

    On the other hand, the light that Sagaritis sends back to us is that of Cybele. There would be a lot to say about the appearance of Sagaritis! It should be a show in its own right, throughout a cycle. It should be fixed in the sky, I already said it, but it has nothing to do in the north. The homins don't really know it, but the habitable lands, Old and New, are on the equator of Atys, at least its "equatorial belt" (don't rely too much on the image representing the planet here and there: it's an "artist's view", not a satellite photo).

    Sagaritis would, if it were "correct" in game, be positioned to the west, a little higher on the horizon and, as we are in the equatorial belt of Atys, we would see its rings vertical (more or less, since Atys is not exactly in the equatorial plane of Sagaritis). So during one half of Atys' turn around Sagaritis, we would see one side of the rings, during the other half the other side, and at each half-period, their edge..

    Sagaritis, comme la Lune vue de la Terre, devrait en outre avoir ses phases : pleine, noire, croissante, ascendante, descendante, etc. Dans la zone de nuit, on verrait souvent des flash d'éclairs et aux pôles, d'immenses aurores boréales. Dans la zone éclairée de Sagaritis on verrait s'enrouler et dérouler des volutes (semblables à celle qu'on voit à la surface de Jupiter et Saturne… pour peu qu'on s'en approche). Ses anneaux brilleraient toujours, qu'elle soit ou non noire, mais parfois une partie serait cachée par l'ombre de sa masse. Inversement, l'ombre des anneaux se projetterait parfois sur Sagaritis. Enfin, Cybèle pouvant passer derrière Sagaritis, on observerait parfois une éclipse.

    Pour poursuivre la comparaison avec notre système solaire, je précise qu'Atys, satellite de Sagaritis, est d'une taille semblable à Mars et présente une gravité légèrement inferieure à 1G.

    La Lune Rousse, quant à elle, est dite aussi Lune d'Ambre, ou encore Lune Karavan, Lune Kami, Lune Tryton. Elle est toujours pleine (pas de phases) et sa taille est variable. Si elle était « juste » en jeu, elle ne serait visible, la nuit seulement, que durant les trois-quarts de chaque cycle vu que, pendant le quart restant, elle serait positionnée au dessus de l'autre face d'Atys.

    Je ne vais pas vous dire exactement quelle est la nature de ce corps celeste. Sachez seulement qu'il ne s'agit ni de roche, ni de glace. En fait sa masse est très faible par rapport à celle d'Atys. Peut-être les trytonistes lui connaîtraient un autre nom encore. Un nom qui sonnerait comme « Ryzom ». Mais je commence là à trop parler…

    Pour en terminer avec l'astronomie, un mot sur le ciel étoilé. Si elle était «correctement représenté » en jeu, il ne tournerait pas durant la nuit, mais bien plus lentement, sur un cycle. Outre les étoiles filantes, on verrait parfois des objets brillants se déplacer rapidement et clignoter.

    J'aimerais maintenant descendre d'un cran en altitude et dire deux mots sur la Canopée. Ses branches courent entre 1 et 2 kilomètres d'altitude et sont d'une épaisseur comprise entre 200 et 500 mètres. Si on s'en tenait à la « vue d'artiste » de la planète évoquée plus haut, elles auraient 300 km d'épaisseur au moins ! Il ferait nuit dessous.

    Pour vous représenter la surface d'Atys, imaginez la même chose que la Canopée, mais plaqué au sol. Elle est donc formée de compartiments, et ces compartiments dessinent comme une map du jeu.

    Comme vous savez, dans le calendrier nous avons des cycles, et des années de Jena et il y a une équivalence entre l'année de Jena et l'année terrestre. Mais pas seulement : en fait, pour en dire plus, la date actuelle 2614, est bien le futur de notre 2021.