NASA scientist explains why Venus is Earth's 'evil twin' (video)

[Admin]

Scientists and engineers from NASA and the European Space Agency want to know a whole lot more about why Venus resembles Earth in so many ways, and yet is so strikingly different.

NASA scientist explains why Venus is Earth's 'evil twin' (video) : Read more

 

[rod]

"The nefarious moniker is revealed to be, in a way, an apt description of why astronomers will be investigating Venus this decade. Scientists and engineers from NASA and the European Space Agency are gearing up to send three new missions to the second rock from the sun. They want to know a whole lot more about the nearby planet, which resembles Earth in so many ways, and yet is so strikingly different."

My observation, some interesting issues are raised when comparing the origin of Earth, Venus, and Mercury using the MMSN and postulated protoplanetary disc. A report back in August 2022, raised some concerns about atmosphere loss in planets around young stars.

ref - Evolution of X-Ray Activity in <25 Myr Old Pre-main Sequence Stars, https://iopscience.iop.org/article/10.3847/1538-4357/ac7c69, 12-August-2022.

My observation. This is an important study. "The observed X-ray luminosities can be so high that an inner Earth-mass rocky, unmagnetized planet around a solar-mass PMS star might lose its primary and secondary atmospheres within a few (several) million years. PMS X-ray emission may thus have a significant impact on the evolution of early-planetary atmospheres and the conditions promoting the rise of habitability." My note. Modeling of x-rays and loss of planetary atmospheres on short time scales, also runs into giant impact for the origin of our Moon as an example. Potential for more atmosphere loss and water.

And from another source, ‘Rocky planets might survive if they get past the war of attrition (removal of dust and gas from the disk), provided they get their magnetic shields up in time. In the case of Earth, though, Dr Henry Richter’s book Spacecraft Earth shows that magnetic fields decline rapidly and can be gone in just a few thousand years – far less time than the millions of years of a star’s energy budget.’…’But as Richter’s book points out, a habitable planet has multiple requirements (at least 15) for complex life.'

Looking at exoplanet sites (http://exoplanet.eu/, and https://exoplanetarchive.ipac.caltech.edu/index.html), there is plenty to chew on concerning super-earths, hot-jupiters, exoplanets with radii 3 or less earth radii size, etc. There is also the issue of how much dust and gas is needed in a protoplanetary disc, comparing to MMSN model and various changes used in simulations over the years.

 

[rod]

This report from 2021 uses a high-speed collision model to explain how Venus and Earth evolved so very differently in the solar nebula and protoplanetary disc.

High-speed impacts may have shaped Venus' history, https://phys.org/news/2021-12-high-speed-impacts-venus-history.html

Reference paper, P41B-03 - The role of early energetic collisions in shaping Venus’ evolution, https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/891443, 16-Dec-2021. "Abstract Venus and Earth have similar masses, densities and distances from the Sun, yet they are radically different rocky worlds. The origin of these differences are debated [1]."

When you factor in the exoplanets, stars like 0.95 to 1.05 solar masses, have numerous examples that contradict our solar system configuration. 887 are found at the exoplanet.eu site with min masses 1.9 earths up to 52 Jupiter masses. 46 exoplanets can be seen with semi-major axis 0.3 to 1.1 au. Radii reported range 1.52 earth radii up to 12.3 earth radii size. Kepler-22 b for example forming here would change everything about our solar system for Venus and Earth, perhaps much more too. Explaining how Venus evolved and Earth with such real differences is challenging