 Three series of astrobiology experiments have been conducted outside the International Space Station between 2008 and 2015 (EXPOSE) where a wide variety of biomolecules, microorganisms, and their spores were exposed to the solar flux and vacuum of space for about 1.5 years.Some organisms survived in an inactive state for considerable lengths of time, and those samples sheltered by simulated meteorite material provide experimental evidence for the likelihood of the hypothetical scenario of lithopanspermia.Several simulations in laboratories and in low Earth orbit suggest that ejection, entry and impact is survivable for some simple organisms.