In response to Skako's inquiry about sources for impact studies:

I've copied portions of my chapters for you on the Cal-Tech study, then the Peking University study:

In 2008, a study at the California Institute of Technology (CalTech)
by Margarita Marinova, then a graduate student in Cal-Tech’s
Division of Geological and Planetary Sciences (GPS), confirmed that
Velikovsky’s proposed planetary impact scenario could make sense
in terms of the types of damage that had been observed to exist on
Mars. It is important to note that, after many trials based on widely
varying parameters, the scenario favored by the researchers attributed
the impact to a body much smaller than Venus and assigned it to
an epoch much earlier than Velikovsky proposes. A Cal-Tech press
release states:

Scientists at the California Institute of Technology have shown
through computer modeling that the Mars dichotomy, as the
divided terrain has been termed, can indeed be explained by one
giant impact early in the planet’s history. . . . This size range of
impacts only occurred early in solar system history. . . . The team
modeled a range of projectile parameters that could yield a cavity
the size and ellipticity of the Mars lowlands without melting
the whole planet or making a crater rim. . . . After cranking 500
simulations combining various energies, velocities, and impact
angles through the GPS division’s Beowulf-class computer cluster
CITerra, the researchers narrowed in on a “sweet spot”—a range
of single-impact parameters that would make exactly the type of
crater found on Mars. . . . The favored simulation conditions outlined
by the sweet spot suggest an impact energy of around 10 to
the 29 joules, which is equivalent to 100 billion gigatons of TNT.
The impactor would have hit Mars at an angle between 30 and 60
degrees while traveling at 6 to 10 kilometers per second.By combining
these factors, Marinova calculated that the projectile was
roughly 1,600 to 2,700 kilometers across.”

I made contact personally with one of the researchers who conducted the study, asking among other things whether any of the tested scenarios involved a body the size of Venus, and if the results of that scenario were favorable - but without direct response to that question.

Jupiter and Saturn are thought to have begun life as rocky worlds
with the mass of at least a few Earths. Their gravity then pulled in
gas from their birth nebula, giving them dense atmospheres. In this
picture, all gas giants should have cores of roughly the same size. Yet
spacecraft-based gravity measurements suggest Jupiter’s core weighs
just two to 10 Earth masses, while Saturn’s comes in at 15 to 30.
New simulations by Shu Lin Li of Peking University in China, and
colleagues, may explain why. They calculated what would happen
when a super-Earth of 10 times the mass of our planet slammed into
a gas giant. The rocky body flattened like a pancake when it hit the
gas giant’s atmosphere, then barrelled into the giant’s core about
half an hour later. The energy of the collision could have vaporised
much of the core. These vaporised heavy elements would then have
mixed with the hydrogen and helium of the gas giant’s atmosphere,
leaving only a fraction of the gas giant’s former core behind. This
could explain not only why Jupiter’s core is so small, but also why
its atmosphere is richer in heavy elements compared with the sun,
whose composition is thought to mirror that of the nebula that gave
birth to the solar system’s planets.

- Laird



Edited 1 time(s). Last edit at 04-Nov-15 21:24 by Laird Scranton.