diatoms

Though this is known from Earth diatoms, not space diatoms...

If diatoms did arrive in meteorites and are the ancestors of Earthly diatoms, you would think they would have shown up in the fossil record earlier.

It seems the larger diatoms seeded in the more recent experiment may actually be better at sequestering carbon.

The way to find extraterrestrial diatoms is not wandering around a warm, moist country poking at dirty rocks.

Well the point of the JOC article was to show that there are diatoms in meteorites.

In the case of diatoms, they were looking for fossilized structures embedded in the rock.

Maybe sculptures such as 'diatoms' is where this technology can excel rather than 'food'.

The diatoms have often been treated as a separate phylum, reflecting their unique features.

Chert (flint, etc.) is probably a better candidate substrate, but again, diatoms of that age would be indistinguishable from the substrate itself.

Only if you assume that evolution hasn't affected earthbound diatoms in any way.

That said, it doesn't exclude the possibility of diatoms having perhaps taken a lengthy space trip at some point in their evolutionary history.

Or even possibly that they continued to live and reproduce in space (diatoms are ~algae, so they really only need water and sunlight).

A Panspermia event would likely have seeded our planet with _bacterial_ life; if "space diatoms" exist, they evolved independently of our own.

Assuming such organisms would exist, would we even be able to call them "space diatoms" when there is no established phylogeny?

Diatoms and bacteria also exhibit an absorbance peak near 2200 Å, which is found to agree with the observed ultraviolet absorbance properties of interstellar grains.

Diatoms are primary producers and the fastest growers.