A limbus mundi elucidation of habitability: the Goldilocks Edge

  title={A limbus mundi elucidation of habitability: the Goldilocks Edge},
  author={Ian von Hegner},
  journal={International Journal of Astrobiology},
  pages={320 - 329}
  • Ian von Hegner
  • Published 15 October 2019
  • Physics
  • International Journal of Astrobiology
Abstract The habitable zone is the circumstellar region in which a terrestrial-mass planet with an atmosphere can sustain liquid water on its surface. However, despite the usefulness of this concept, it is being found to be increasingly limited in a number of ways. The following is known: (i) Liquid water can exist on worlds for reasons unrelated to its specific distance from a star. (ii) Energy sources can exist for reasons unrelated to the distance to a star. Furthermore, the habitable zone… 

First principles of terrestrial life: exemplars for potential extra-terrestrial biology

In this discussion of life, a framework will be formulated that, based on the dynamic relationship between mesophiles and extremophiles, will be imposed on exoworlds in order to utilize the graph's predictive power to analyze how extra-terrestrial life could unfold.

Stellar metallicity is a key parameter for the search of Life in the Universe

The search for Life in the Universe generally assumes three basic life’s needs: I) building block elements ( i.e. CHNOPS), II) a solvent to life’s reactions (generally, liquid water) and III) a

Extreme exoworlds and the extremophile paradox

The use of extremophiles as analogues to extraterrestrial life has limitations due to the very conditions evolution operates under, although analysis of these conditions provides conceptual tools for the search for life elsewhere in the solar system and beyond.



Geologica: Earth’s Dynamic Forces

  • Elanora Heights, NSW: Millennium House
  • 2007

Delayed onset of runaway and moist greenhouse climates for Earth

As the Sun slowly grows brighter over its main sequence lifetime, habitability on Earth's surface will eventually become threatened probably leading to moist and then runaway greenhouse climates.

The terrestrial record of Late Heavy Bombardment

Small but Mighty: Cell Size and Bacteria.

The impact of size on bacterial evolution, physiology, and morphogenesis is reviewed.

Evidence of Archean life: Stromatolites and microfossils

Potentially biogenic carbon preserved in a 4.1 billion-year-old zircon

Carbon isotopic measurements on graphite inclusions from Jack Hills, Western Australia are reported to be consistent with a biogenic origin and may be evidence that a terrestrial biosphere had emerged by 4.1 Ga, or ∼300 My earlier than has been previously proposed.

Extremophiles: a special or general case in the search for extra-terrestrial life?

Depending on whether it is difficult or easy for worlds to maintain the habitability, the search for extra-terrestrial life with a focus on extremophiles will either represent a search for dying worlds, or aSearch for special life on living worlds, focusing too narrowly on extreme values.

Lithoautotrophic Microbial Ecosystems in Deep Basalt Aquifers

Bacterial communities were detected in deep crystalline rock aquifers within the Columbia River Basalt Group (CRB). CRB ground waters contained up to 60 μM dissolved H2 and autotrophic microorganisms

Full House: The Spread of Excellence from Plato to Darwin

The Life and Letters of Charles Darwin: Including an Autobiographical Chapter

The spread of evolution is discussed, including second editions of 'Coral Reefs', the 'Descent of Man' and the 'Variation of Animals and Plants' 1874-1875.