With a mechanical gripper Koshi manages to collect one of the spore bags before it bursts. To enable him to bring it intact into the shuttle, Dray has to hold the craft immediately above the surface while Koshi manoeuvres his catch into the hold. Mil considers this a masterpiece of ship handling. As soon as the cargo hatch is closed, the captain insist on loosing no more time and continuing the flight immediately. He wants to reach the polar region today, if possible, as he intends to check the zone where the climate is too cold for big trees. Mil believes there to be sort of tundra zone with a cold resistant vegetation. If she's right, this might be the ideal spot to start human settlement. While the shuttle speeds on, she resumes her research.

By now, she is well aware Emerald trees show significant differences to their Earth counterparts. For example there are the remarkable holes or pores with up to several centimetres of diameter. They reach from the surface right into the centre of the wood and are present with all tree species. They only differ in their form, the cross-sections varying from round to triangular and star-shaped. In the beginning, Mil concentrated her studies on the outer, younger layers of the wood. In analogy to Earth trees she assumed that all the interesting things would be found there. Now she observes for the first time that the pores tanker towards the trunks centre until they are hardly discernible.

Mil checks on some of the whole tree slices. The pores always reach the pith, clearly visible in the centre of the trunk. Here, the vessels are wider than the trachea in the tree rings of the heartwood. The radial pores connect the pith with the bark, the outer surface of the trunk. A liquid test allows Mil to prove this without a doubt. Now, she racks her brain over the significance of this observation. On the inside, the pith vessels are lined with a netlike layer of small but complex cells. Mil doesn't understand their function. Up until now she has never seen anything like it and a search in the library section of the main computer doesn't get her any further.

Frustrated by the stagnation in her research, Mil stands up to stretch her legs. She decides to pay a visit to Carlos in the engine room. He dismantled the Mellow-accumulator and his working table is littered by tools, measurement equipment and lots of tiny components. Carlos glances quickly at Mil and shakes his head in denial. She fetches him some coffee anyway and leaves the cluttered room to let him work, well aware how much depends on the technician's inventiveness.

Andrej installed himself in the operations centre, working on his own theory regarding the cyclic climate phenomenon striking the Emerald forest every 579 years. As Mil enters the room, the astrophysicist looks up from his screen with a content smile.

"You drop by just at the right moment. I have something interesting for you, sit down."

Curious, Mil follows the simulation Andrej starts on his working screen. He programmed a three dimensional digital model of Emerald's system, complete with both moons and the four outer planets they found so far. In addition, there is a broad belt of asteroids as well as a cluster of minor planets between the forth and fifth planet. Andrej directs Mil's attention to a sixth, big but dark planet travelling on its trajectory far away from the central star.

"Can you see this planet? I only found it today, it's hardly visible in reality. Right now, it nears he point furthest out on a very unusual ecliptic orbit. Wait, I'll show you."

He accelerates his simulation and Mil starts to understand. The dark planet now travels towards the central star with increasing speed. Finally it rounds the local sun way on the inside of Emerald's traditional circular orbit. The rogue planet picks up high velocity before it catapults itself once again out of the zone of the five inner planets.

"In approximately 250 years, the dark planet passes very close to the central star. It will probably approach near enough to significantly disturb the outer gas layers of the sun. This will cause higher radiation and increased activity of solar spots."

Mil studies the simulation of the six planets floating above Andrej's screen, fascinated. She understands immediately what he wants to show her.

Changes in solar activity result imperatively in climatic strains. The effects may reach from heavy gales to thunderstorms, maybe worse. Higher radiation on the other hand will cause warming and thus probably draughts. The consequence might be the omnipresent water bodies drying out and the big leaves of the trees withering.

Together with thunderstorms, the probability of forest fires will rise significantly. The resulting ashes in the atmosphere will very likely obscure the sunlight for years, causing the mean temperature to drop and severely hindering the growth of the trees. Andrej's stops the simulation.

"There you have the reason for your little ice age. This cycle repeats every 579 years."