After the success of Sputnik 1 in October 1957 by USSR, they decided to launch Sputnik 2 by November, and this left them with only 4 weeks to design and build the spacecraft. Sputnik 2, therefore, was something of a rush job, with most elements of the spacecraft being constructed from rough sketches. It was decided that Sputnik 2 would carry a canine, thus repeating the triumph of Sputnik 1. Three dogs were trained for Sputnik 2 flight- Albina, Mushka and Laika.