Planet s dating
Planet s dating - blue collar and white collar dating
On other solid-surfaced worlds -- which I'll call "planets" for brevity, even though I'm including moons and asteroids -- we haven't yet found a single fossil.Something else must serve to establish a relative time sequence. Earth is an unusual planet in that it doesn't have very many impact craters -- they've mostly been obliterated by active geology.
Relative-age time periods are what make up the Geologic Time Scale.The Geologic Time Scale is up there with the Periodic Table of Elements as one of those iconic, almost talismanic scientific charts.Long before I understood what any of it meant, I'd daydream in science class, staring at this chart, sounding out the names, wondering what those black-and-white bars meant, wondering what the colors meant, wondering why the divisions were so uneven, knowing it represented some kind of deep, meaningful, systematic organization of scientific knowledge, and hoping I'd have it all figured out one day.The science of paleontology, and its use for relative age dating, was well-established before the science of isotopic age-dating was developed.Nowadays, age-dating of rocks has established pretty precise numbers for the absolute ages of the boundaries between fossil assemblages, but there's still uncertainty in those numbers, even for Earth.Valerian and Laureline help keep peace in the universe throughout both space and time by working as special government operatives for the Spatio-Temporal Service of the Terran Galactic Empire.
Valerian hopes to start a romantic relationship with Laureline, but she often pushes him away because of his past relationship history.Just like a stack of sedimentary rocks, time is recorded in horizontal layers, with the oldest layer on the bottom, superposed by ever-younger layers, until you get to the most recent stuff on the tippy top.On Earth, we have a very powerful method of relative age dating: fossil assemblages.The chronostratigraphic scale is an agreed convention, whereas its calibration to linear time is a matter for discovery or estimation. We can all agree (to the extent that scientists agree on anything) to the fossil-derived scale, but its correspondence to numbers is a "calibration" process, and we must either make new discoveries to improve that calibration, or estimate as best we can based on the data we have already.To show you how this calibration changes with time, here's a graphic developed from the previous version of Fossils give us this global chronostratigraphic time scale on Earth.A few days ago, I wrote a post about the basins of the Moon -- a result of a trip down a rabbit hole of book research.