|"Birth of a Moon" (Europa, actually) found HERE.|
Or should I say our parthenogenic Earth?
Parthenogenesis (from the Greek "παρθένος," parthenos/virgin & "γένεσις," genesis/origin), is the term applied to reproduction without fertilization, i.e., asexual reproduction. In parthenogenesis, an egg from the maternal source develops into a viable offspring without being fertilized by a spermatozoon.
I have always found parthenogenesis fascinating, particularly since when I was a child I was (mis)taught that it did not exist outside of plants & protists -- that it was a myth concocted by some poor, mistaken soul's misinterpretation of the origin of maggots. The truth is that some variation of parthenogenesis occurs in a wide variety of Earthly life forms; plants, protists, invertebrates, sharks, herpeptiles & domesticated poultry (chickens & turkeys). Parthenogenesis has also obviously been artificially induced in mammals through cloning & stem-cell experiments.
Ah, the Moon... where does She fit into this?
In recent years, the giant-collision scenario has been the favoured model for explaining our Moon's origins. Basically, this model suggests that our Moon comes from a two-parent merger; the proto-Earth & a hypothetical planetary body (aka impactor material) dubbed "Theia" came together (no doubt a bit violently) with the pleasant end result of our Moon's birth... (Theia & Gaia... that gives me pause to wonder -- on so many levels -- but that is not the focus here & it certainly is not parthenogenesis.)
However, a very ambitious graduate student at the University of Chicago has been doing some revealing paternity testing on the Lady's Moon-stuff brought back by the Apollo lunar expedition:
"Analyses of lunar samples reveal isotopic homogeneity in titanium, a highly refractory element, suggesting lunar material was derived predominantly from the mantle of the proto-Earth." -- Nature GeosciencePut simply, the paper, The proto-Earth as a significant source of lunar material (Zhang, et. al.), published in Nature Geoscience on March 25, suggests that the material collected from the Moon has only one origin: the Earth. In the words of one of Ms. Zhang's co-authors, Dr. Nicholas Dauphas:
“What we found is that the child does not look any different compared to the Earth. It’s a child with only one parent, as far as we can tell.” -- EarthSkyThe mechanics of this single-parent birth remains a mystery.
I am humming with Sciento-awe! With every new discovery, She only gets better, no? Pardon me a moment while I meander into dubious territory, but given this explanation, is there any mystery about the connection we feel to this Lady-Earth-Moon-Clone?
Looks like She just might be a parthenogenic babe of epic proportions & really, how awesome is that?
Addendum: If you are interested in reading more about this but find the technical language at Nature mind-numbing, there is an excellent article at EarthSky: Titanium paternity test fingers Earth as moon’s sole parent