Men into Space by Murray Leinster — Read

(It seemed there wasn't much left to do in the way of space pioneering. There was a Space Platform, and there were bases on the moon, and drone ships had been out to Mars and sunward past Venus. There were new and better fuels, and the problem involving the Van Allen belts of highly charged atomic particles seemed to have been solved. It looked as if the rest of the job of conquering space would be just plain, slogging hard work of a strictly routine nature. This process would be improved a little, and that would be developed a little further, and progress toward the stars would be made by inches. But things never work out simply. There is always something unexpected and usually disastrous turning up. Just when things looked brightest, somebody worked out the causes of solar flares and devised a way to predict them. It looked like a neat and unimportant triumph of pure theory. But when it was closely examined, it meant that the end of all space travel was approaching.)

They called Colonel Ed McCauley back from the moon when Doctor Bramwell peevishly refused to go along with the Venus shoot unless the assigned crew was fired and replaced by more respectful men. The top brass felt that McCauley might be able to get along with Bramwell and get the job done. It was a highly necessary job. There was a sun-flare maximum coming up, but if the Bramwell-Faraday screen could be improved enough, it might not matter. Men might continue to occupy the Space Platform, and activities at the bases on the moon might continue. All the men now in space might not have to return to Earth to stay until the flares died down -- if they ever did. In effect, if the Bramwell-Faraday screen could be built up to adequate strength, man's conquest of space might continue. If the screen couldn't be built up, space travel must stop.