English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We revisit the hypothesis that there is life in the Venusian clouds topropose a life cycle that resolves the conundrum of how life can persist aloftfor hundreds of millions to billions of years. Most discussions of an aerialbiosphere in the Venus atmosphere temperate layers never address whether thelife-small microbial-type particles-is free floating or confined to the liquidenvironment inside cloud droplets. We argue that life must reside inside liquiddroplets such that it will be protected from a fatal net loss of liquid to theatmosphere, an unavoidable problem for any free-floating microbial life forms.However, the droplet habitat poses a lifetime limitation: Droplets inexorablygrow (over a few months) to large enough sizes that are forced by gravity tosettle downward to hotter, uninhabitable layers of the Venusian atmosphere.(Droplet fragmentation-which would reduce particle size-does not occur inVenusian atmosphere conditions.) We propose for the first time that the onlyway life can survive indefinitely is with a life cycle that involves microbiallife drying out as liquid droplets evaporate during settling, with the smalldesiccated 'spores' halting at, and partially populating, the Venus atmospherestagnant lower haze layer (33-48 km altitude). We, thus, call the Venusianlower haze layer a 'depot' for desiccated microbial life. The spores eventuallyreturn to the cloud layer by upward diffusion caused by mixing induced bygravity waves, act as cloud condensation nuclei, and rehydrate for a continuedlife cycle. We also review the challenges for life in the extremely harshconditions of the Venusian atmosphere, refuting the notion that the 'habitable'cloud layer has an analogy in any terrestrial environment.

The Venusian Lower Atmosphere Haze as a Depot for Desiccated Microbial Life: A Proposed Life Cycle for Persistence of the Venusian Aerial Biosphere