What could it possibly be like down there, on a planet where heat and light derived from two totally different sources? E.C. ran his atmospheric convective models using a variety of different initial conditions and assumed atmospheres, and found his results inconclusive. There was only one way to obtain answers that were undeniably correct. He would have to head down, and see for himself.
But not quite yet. Slow and easy.
There was one other peculiarity about the world below. E.C. had visited dozens of planets, and he held stored in his data bases information about thousands more. This was like none of them, and it failed to conform to any theoretical models. The magnetic field that he measured was huge, orders of magnitude higher than seemed possible for such a planet.
Tally could imagine only one explanation. At the center of the planet must be a rapidly spinning metal core, whose dynamo effect generated the magnetic field. But then, that core must somehow be physically decoupled from the planetary mantle and surface, since the inside was turning hundreds of times as fast as the outside. E.C. filed that oddity away, for future analysis.
At the moment he faced a more immediate issue. He would probably not gain more useful information from orbit. It was time to consider a descent.
He analyzed the problem. Simple re-entry was easy. The suits on the Pride of Orion were designed to permit a descent with no help from a ship. Once down, however, he would be stuck there—the suits, sophisticated as they were, lacked the power needed for an ascent to orbit.
He would worry about a return when the time came. For the moment, the question was, what insert parameters should he use to land as close as possible to one of the bursts of radio signal?
He was hampered by a lack of knowledge of atmospheric parameters. He could estimate the gaseous mix, but the density profile was much more difficult. E.C. was forced to adopt a fatalistic attitude. He would make his best estimates, and fly in. If he was grossly off, not even this suit could fully protect him. It would burn away with the heat of re-entry. His human embodiment would survive only a few seconds longer. It was conceivable that what would finally reach the ground would be only E.C. Tally’s grapefruit-sized brain. It would be in perfect working order, but lack a means of sending information to or receiving information from the outside world.
Well, thank heaven for his stand-by mode. If he had to, he would switch off and wait—wait, either for his awakening in a new embodiment or for the end of the universe, whichever came first.
E.C. made the orbit adjustments needed for a re-entry vector that would bring him in at a scruff of radio signal nearest to the warm hemisphere. It also lay at the planetary equator, so it should be easy to reach. He waited for the exact microsecond, then initiated the suit’s built-in drive. He felt a burst of deceleration, powerful but of short duration. Then there was nothing to do but watch and wait.
The planet sped by beneath him. He had changed attitude, so that the feet of his suit now led the way. A new deceleration, slight at first but slowly increasing, told him that he was within the upper limits of the atmosphere. The forces on his body grew and grew. His suit’s extremities glowed white-hot with frictional heat. E.C. felt satisfaction. All was nominal, all was normal. If the profile continued he would land within a few kilometers of the estimated center of his target source of radio noise.
Upon landing his body would require food and drink, but after that a walk across the surface—with, or even without his suit—would be no problem.
E.C. watched as the glow of frictional heating faded. His thoughts were already moving on, to who or what he might encounter on the ground. A central part of his reason for existence was the collection of new data. He was without a doubt going to exercise that function before the current day cycle on his new planet was complete.
A suit brought you to the surface at an acceptably low speed, but it made no guarantees as to the type of terrain that you might encounter. Tally plopped down feet-first into cold and sticky swamp, coated with a spongy layer of some kind of moss. Even so, he was lucky. A landing fifty meters to his left would have dropped him into standing water of unknown depth.
His legs pulled free with an ugly sucking sound, and he squelched his way toward a higher point of land. He tried to avoid treading on the dozens of small creatures that lay on the ground in front of him, until he realized that none was moving. He bent low and picked one up. It was dead. Presumably they were all dead. Tiny mummified bodies crackled and crunched unpleasantly beneath his feet as he walked.
When he was completely clear of the gluey mud he checked his location. He was just seventeen kilometers from his target. Not bad at all, given the uncertainty in his information about the planet. He could be at the source of the radio signals in just a few hours.
But first things first. He must make observations. This was an unknown world, with unknown dangers. Tally stared around. The gas-giant hovered just above the horizon, where it would remain permanently. It would be many hours before the arrival of night, but a cold, gusting wind blew from his right—the direction opposite to the source of warmth. He was in a permanent “temperate zone.” The surface received a constant supply of heat, but a supply much diminished by the large slant angle from the heat source. At this location, the contribution from the parent star would make a critical difference. Life survived easily enough but it would never run riot, as it should in regions where heat from the gas-giant had its full impact. At night, the temperature at this location would fall far enough for open patches of water to form a surface layer of ice.
Atmospheric mixing would guarantee the same general composition of the air over the whole planet. Tally’s sensors indicated that an unusually large percentage of that air consisted of the inert gases neon and argon. But he, and most other species from the Orion Arm, could breathe it with no ill effects.
He cracked open the faceplate of his suit and sniffed the air. The wind had a chill edge, more bracing than cold. Faint and unfamiliar odors filled his nostrils. It was a pity that the wind came from the cold side of the planet. The scents of life would be stronger and more revealing if they came from the hot side. But idle wishing for circumstances different from what you had was a waste of time. He had chosen this landing spot for other reasons.
Slow and easy.
Was there anything else that he ought to do before he sought the source of those scruffy bursts of radio noise? Tally could think of none. Here he was, and here, until someone came with a ship able to take him back to space, he would stay.
Choosing his path carefully so as to remain on dry land, he started to walk in the direction exactly opposite to the hovering gas-giant; away from warmth, toward the cold side. Toward the unknown source of the radio signals.
When you had little or no information, it was unreasonable to have any expectations. But somehow you did, even if they were often wrong.
Tally had noticed in the final moments before he landed that the local terrain contained plentiful hills and valleys. But the path that he was following, homing in on the intermittent radio chatter, constantly ascended. He was moving higher and higher, and the external temperature constantly dropped. By the eighth kilometer of his march, Tally was forced to close his faceplate so as to ensure the well-being of his flesh-and-blood embodiment.