The rocket launcher was already set up near the boat. It was a simple affair, with four adjustable legs bolted to ground spikes. The legs held a movable cradle in which the rocket racks were placed. High-geared hand controls enabled the gunner to swing the cradle at high speed in any direction except straight down. A simple, illuminated optical sight was all the gunner needed. Since there was no gravity and no atmosphere in space, the missiles flashed out in a straight line, continuing on into infinity if they missed their targets. Proximity fuses made this a remote possibility. If the rocket got anywhere near the target, the shell would explode.
Rip found his astrogation instruments set carefully to one side. He took the data sheets from his case and examined them. Now came the work of finding the exact spots in which to place his atomic charges. Since the computer aboard ship had done all the mathematics necessary, he needed only to take sights to determine the precise positions.
He took a transit-like instrument from the case, pulled out the legs of its self-contained tripod, then carried it to a spot near where he had estimated the[pg 086] first charge would be placed. The instrument was equipped with three movable rings to be set for the celestial equator, for the zero meridian, and for the right ascension of any convenient star. Using a regular level would have been much simpler. The instrument had one, but with so little gravity to activate it, the thing was useless.
The sights were specially designed for use in space and his bubble was no obstacle in taking observations. He merely put the clear plastic against the curved sight and looked into it much as he would have looked through a telescope on earth.
As he did so, a hint of pale pink light caught the corner of his eye. He backed away from the instrument and turned his head quickly, looking at the colorimeter-type radiation detector at the side of his helmet. It was glowing.
An icy chill sent a shiver through him. Great, gorgeous galaxies! He had forgotten ... had Koa and the others? He turned so fast he lost balance and floated above the surface like a captive balloon. Santos, who had been standing near by to help if requested, hooked a toe on a ground spike, caught him, and set him upright on the ground again.
"Get me the radiation detection instruments," he ordered.
Koa sensed the urgency in his voice and got the instruments himself. Rip switched them on and read the illuminated dial on the alpha counter. Plenty[pg 087] high, as was natural. But no danger there—alpha particles couldn't penetrate the space suits. Then, his hand clammy inside the space glove, he switched on the other meter. The gamma count was far below the alpha, but there were too many of the rays around for comfort. Inside the helmet, his face turned pale.
There was no immediate danger. It would take many days to build up a dose of gamma that could hurt them. But gamma was not the only radiation. They were in space, fully exposed to equally dangerous cosmic radiation.
The Planeteers had gathered while he read the instruments. Now they stood watching him. They knew the significance of what he had found.