Hydrogen atom loss aka "H loss" vs Magnetosphere as the secret origin of life on Earth: EMANATE

 Earth’s magnetic field and its relationship to the origin of life, evolution, and planetary habitability (2024)

 Huang et al. [78] presented a hypothesis that links the UL-TAFI, oxygenation and animal evolution through magnetospheric H loss to space.

 To effect oxygenation, H loss must be substantial, and this requires that supply from the lower atmosphere [150] must have been greater during the UL-TAFI relative to present.
Huang et al. [78] noted that with decreased magnetic field, greater penetration of highly energetic protons is expected, resulting in the formation of NOx compounds which can create ozone holes [151]. With the greater UV flux in a depleted ozone layer, more dissociation of water vapor [152] should occur, increasing the supply of H available for loss.

 Data indicating a magnetic field at 4.2 Ga [17,35] also provide evidence for a magnetospheric shielding of the atmosphere. This early establishment of the geodynamo is consistent with nitrogen isotopic values indicating limited nitrogen fractionation that would have otherwise been associated with the absence of a global magnetic field [17]. The 4.2 Ga age also corresponds to the time of the last common universal ancestor (LUCA) determined by genetic studies [70] (Figure 9). The presence of a Hadean magnetic field shielding sterilizing solar energetic particles and galactic cosmic rays [120] potentially widens the range of environments for the origin and earliest development of life to include sites without meters of overlying water needed for shielding in the absence of a magnetic field (e.g. shallow lakes [154]). Such life might still need to contend with greater UV radiation [155-156], but estimates of the increase relative to the present depend in turn on model choices for the Hadean atmospheric composition.

 Sagan [2] hypothesized that in the absence of a magnetic field the influx of solar energetic particles could cause organic molecules to be produced just below the troposphere and that these could be transported to the Earth’s surface through atmospheric convection. More recent magnetohydrodynamic simulations of the intense solar wind conditions in of this earliest terrestrial episode - with a geomagnetic field - also predict the formation of organic precursors to life [162] relying in part on funneling of charged particles toward the polar caps. Thus, there seem to be dual pathways in which the magnetic field, or its absence, could have been associated with the formation of the precursors of life.

If correct, our proposition, called here the EMANATE Hypothesis for short (Earth’s Magnetism Allowed New Animals To Evolve) represents a new twist in how Earth’s magnetic field is related to life. In this case, it was the weakness of the field, rather than its strong intensity and stand-off of the solar wind, that was the key factor that assisted this seminal event in animal evolution