Chapter Text
Sputnik 2 was part of an idea that included Sputnik 1 that came from Korolev that was approved in January 1957. At that time, it was not clear that the Soviets' main satellite plan (which would eventually become Sputnik 3) would be able to get to space because of the ongoing issues with the R-7 ICBM, which would be needed to launch a satellite of that size. “Korolev proposed substituting two 'simple satellites' for the IGY satellite”. The choice to launch these two instead of waiting for the more advanced Sputnik 3 to be finished was largely motivated by the desire to launch a satellite to orbit before the US.
Sputnik 2's launch vehicle had several modifications for the mission. These included modifying the launch trajectory to utilize propellant more efficiently and removing some flight control components to reduce weight. In addition, the core stage would be burned to propellant depletion instead of cutting off at a preset time. The telemetry system at engine cutoff would be switched from monitoring the booster's parameters to those of the capsule. It was also designed to only transmit data for ten minutes at a time every 90 minutes, so as to prevent battery power from being used up sending data while the spacecraft was out of range of Soviet tracking stations. The interstage section between the booster and capsule was highly polished and equipped with thermal blankets so as to reflect off sunlight and keep the latter cool, also several deployable reflectors were mounted on the core stage. A braking nozzle was added to the core stage to prevent it from tumbling in orbit; this would work by venting excess helium gas from the propellant tank pressurization system. Several RD-107 engines were test-fired, with the best-performing units being selected for use on Sputnik 2's booster. The launch vehicle arrived at Baikonur on October 22, along with various parts of the capsule. On November 1, the booster was erected on LC-1.
Ten dogs were considered for the mission, with the final selection being narrowed down to three, Laika being the flight animal, Albina the backup, and Muhka, used to test equipment.
Liftoff took place at 5:58 AM Moscow time on November 3. Booster performance was nominal and the command to terminate core stage thrust was issued at T+297 seconds, just as onboard sensors detected LOX depletion. The booster and capsule entered a 140 miles by 1,038 miles orbit at a 65 degree inclination.
During the first two orbits, it proved difficult to reliably track Sputnik 2's flight path, but ground controllers were able to intercept theodolite data from an American tracking station in Quito,Ecuador. Data showed that Laika's heart rate and breathing spiked rapidly during ascent, but she otherwise reached orbit largely unscathed.
The three days that Sputnik 2 spent on orbit were largely spent doing various biological tests on Laika. She adjusted to orbit,although imperfectly,and ate and drank at preselected times from food and drink canisters in her cabin. Late on the first day,the spacecraft was separated from its booster. The booster remains in an orbit of around 680 by 925 miles,the oldest man-made satellite still circling around Earth. It is expected to reenter the Earth’s atmosphere sometime in the 24th century.
On November 7,it came time to return Laika to Earth. Her cabin separated from the rest of Sputnik 2 (which reentered the atmosphere in July 1963) and was deorbited over Angola. The reentry seemed to occur normally and the capsule landed near Zhinvali in the Georgian SSR at 12:41 PM Moscow time.
At first,the post-landing status of Laika was confused.