China Daily, an English-language newspaper in the Asian country, says the spacecraft sent back data and images taken from within the chamber housing the specimens every four hours. One of the photos it posted was captured four hours before SJ-10 blasted off, while the other showing the embryos in their more advanced blastocyst stage was captured 80 hours after it left Earth.

Since it's a short experiment, we still don't know if the embryos would have grown properly to produce live mice. SJ-10's lead researcher Duan Enkui says, however, that while we have a ways to go before becoming a spacefaring species, we at least know now that "the most crucial step in our reproduction" is possible outside the planet.

Shijian 10's re-entry capsule has just landed in Mongola carrying 11 of the 19 experiments. The other eight are still in orbit aboard the other half of the spacecraft. Despite spending 12 days in orbit, the embryos are frozen in the blastocyst stage you see below, as the scientists used chemicals to prevent them from developing any further. Authorities will ship the blastocysts to Beijing, where they will be studied and compared to embryos that developed here at home.

Images of China's Shijian-10 space science re-entry capsule landing at 08:30 UTC today pic.twitter.com/Bk5JdDCUi8 — Andrew Jones (@AJ_FI) April 18, 2016

[Image credit: ChinaDaily (in-line embryo pictures)]