The deadly atmosphere on Venus could help us find habitable worlds. Here's how

"For the study, the researchers examined the atmospheres of what are known as exoVenuses, which are exoplanets that lie within the Venus Zone (VZ), or inside the runaway greenhouse boundary of their parent star's orbit. Astronomers hope to use exoVenus atmospheres as analogs to not only better understand the runaway greenhouse effect of Venus, but its past, as well."

My notes. I read several reports recently on the VZ. Here are some examples.

Hunting Venus 2.0: Study narrows James Webb Space Telescope targets,

ref - The Demographics of Terrestrial Planets in the Venus Zone,, 21-March-2023. "Abstract Understanding the physical characteristics of Venus, including its atmosphere, interior, and its evolutionary pathway with respect to Earth, remains a vital component for terrestrial planet evolution models and the emergence and/or decline of planetary habitability."

This forums discussion on Venus was interesting. NASA scientist explains why Venus is Earth's 'evil twin' (video),

GJ 3929: High Precision Photometric and Doppler Characterization of an Exo-Venus and its Hot, Mini-Neptune-mass Companion,

Now we have some recent reports where potential smaller, rocky exoplanets show no atmospheres.

James Webb Space Telescope finds no atmosphere on Earth-like TRAPPIST-1 exoplanet,

We also have some new reports from JWST where gas giant planets like Saturn size do not follow our solar system metal content. Too much carbon relative to oxygen likely leads to planets with little or no water evolving from their postulated protoplanetary discs.

At the moment, with more than 5300 exoplanets documented now, Earth definitely has life on it, a fossil record, and plenty of water. Still waiting to see confirmation of a habitable exoplanet with these same properties. Rare Earth? So far, very rare Earth.
Here is a report on Venus showing 85,000 volcanoes documented now on the planet.

Scientists share 'comprehensive' map of volcanoes on Venus—all 85,000 of them,

ref - A Morphological and Spatial Analysis of Volcanoes on Venus,, 24-March-2023. "Abstract Venus is home to many thousands of volcanic landforms that range in size from much less than 5 km to well over 100 km in diameter. Volcanism is clearly a major, widespread process on Venus, and is a principle expression of the planet’s secular loss of interior heat. Without sufficient in situ data to clearly determine its internal structure, we can use the morphological and spatial characteristics of volcanoes across the planet to help place constraints on our understanding of the volcanic characteristics and history of Venus. With the Magellan SAR (synthetic-aperture radar) FMAP (full-resolution radar map) left- and right-look global mosaics at 75 meter-per-pixel resolution, we developed a global catalog of volcanoes on Venus that contains ∼85,000 edifices, ∼99% of which are <5 km in diameter. We find that Venus hosts far more volcanoes than previously mapped, and that although they are distributed across virtually the entire planet, size–frequency distribution analysis reveals a relative lack of edifices in the 20–100 km diameter range, which could be related to magma availability and eruption rate. Through spatial density analysis of volcanoes alongside assessments of geophysical datasets and proximal tectonic and volcanic structures, we report on the morphological and spatial patterns of volcanism on Venus to help gain new insights into the planet’s geological evolution."

I am glad I live on the very rare planet Earth.
Following what I pointed out in post #4, applying to exoplanet studies for the Venus Zone (VZ), just how many are volcanically active, present or past? Venus in our solar system, the volcanic record appears now more detailed and large-scale volcanic activity could play a major role in planet wide catastrophism. I notes these exoplanets from the article I mentioned directly.

"The researchers then calculated the potential for follow-up studies, eight of which will be observed by the James Webb Space Telescope (JWST), including GJ 357 b, GJ 1132 b, TRAPPIST-1 b, TRAPPIST-1 c, TOI-776 b, TOI-776 c, LTT 1145 A b, and L 98-59 b. "I would say that the most important targets are those that have multiple terrestrial planets within the Venus Zone," Dr. Stephen Kane..."
Apr 18, 2020
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Perhaps 1bn years ago the Venusians were as stupid as humans appear to be today and started the runaway greenhouse effect.
1bn years ago on Earth, it was the Proterozoic Eon, during which plants formed, and the earliest animals. So it's not likely there were any Venusians then who were smart enough to be stupid.
Well, here is a paper that claims exoplanets do not exist. If this model is correct, astrobiology falls apart as science :)

A Modest Proposal for the Non-existence of Exoplanets: The Expansion of Stellar Physics to Include Squars,

My observation. The 7-paged PDF report attached. "5.1. Elegance Over Opulence Widespread acceptance of exoplanet detections is nothing short of a modern-day Ptolemaic fiasco. The constant addition of super
uous orbiting bodies in oder to reproduce observed data is clearly reminiscent of the historic heliocentric vs. geocentric tension. Before the adoption of the heliocentric model, epicycles were invoked to explain the motions of heavenly bodies under the preconception that the geocentric model must be an immutable truth (Ptolemy 150-170 CE). Similarly, exoplanets have been used as the great panacea of the modern age. Indeed, accepting exoplanets as established truth has enabled the rapid publishing of under-scrutinized and over-hyped scientific hypotheses that only serve to advance fame, glory, and wealth, which are so often asso-ciated with the profession of academic astronomy. But just as Galileo stood before the church, so do we stand against Big Exoplanet."

My note, the paper has a picture of a stellar squar, shaped like a square or cube. "Figure 4. While much of the stellar astrophysics community lags behind in the study of squars, advanced simulations such as Minecraft™ have already implemented squars into their universe." "5.3. Final Thoughts We have discovered a new field of astrophysics that not only simplifies our understanding of the universe but also eradicates the need for exoplanets."

Okay, no exoplanets, no abiogenesis in other areas in our galaxy :)
Sep 11, 2022
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Squars, huh? Either this paper was written in all seriousness by one of the regulars posting in this forum's Cosmology comments section, or ... (checks date) ... hmmm