They can go in incubator now. They can be put in incubator 2 days after set or up to 8 days. The duck egg that was layed yesterday can be but wait a day or 2 for the newer ones. I would wait a while until you have a clutch of eggs that are needed, the eggs will be fine up to 8 days.
At last, on January 31, 1958, the United States succeeded in launching its first satellite, the Explorer. The Explorer was still slighter than Sputnik, but its launch sent it deeper into space. The Soviets responded with yet another launch, and the space race continued.
Their lobbying would lead to the launch of the first artificial Earth satellite, the USSR's Sputnik 1, in November 1957. It was done almost as an afterthought, but it set in motion a space race that quickly acquired a momentum of its own.wo of the big Object D satellites had been completed and were ready to fly into space. The first shot, on 27 April 1958, ended in a launch failure. The second attempt, on 15 May 1958, was successful, with Sputnik 3 placed in Earth orbit.