Interplanetary dust, dust that has come from comets, asteroids, and leftover debris from the birth of the solar system, continually rains down on Earth and other Solar System bodies. These particles are bombarded by solar wind, predominately hydrogen ions. This ion bombardment knocks the atoms out of order in the silicate mineral crystal and leaves behind oxygen that is more available to react with hydrogen, for example, to create water molecules.
“Perhaps more exciting,” said Ishii, “interplanetary dust, especially dust from primitive asteroids and comets, has long been known to carry organic carbon species that survive entering the Earth’s atmosphere, and we have now demonstrated that it also carries solar-wind-generated water. So we have shown for the first time that water and organics can be delivered together.”
The fact that interplanetary dust arriving on Earth has been shown to include water and organics is interesting, but it’s unclear that it is significant. As the researchers admit, the solar wind is probably not a significant source of water, of which Earth wasn’t short anyway. Organic chemicals (CHNOPS) were probably not absent either.
Now, if they had just found some fossil bacteria … 😉
Note: I’ll shortly be starting a second Science Fictions series, this one on the search for the origin of life. Stay tuned.