A wild new study claims that Jupiter may have gobbled up nearby planets to become the space behemoth that it is today. Now, Jupiter is not the only body out there that is known to have engaged in some cosmic cannibalism. A study published earlier this year detailed a phenomenon called “stellar vampirism” in which a larger star sucked the atmosphere out of a neighboring star in the system named HR 6819. Also known as blue stragglers, a few such stars exist at the heart of the Milky Way galaxy as well. Galaxies are also known to engage in vampirism when they can’t find enough hydrogen to support star formation in their own cradle.
But planets like Jupiter are a different beast. So far, it was believed that Jupiter’s mass mostly comes from external pebbles that form its solid core. However, a key limitation to that theory is that once the planet’s outer gaseous shell is dense enough, it would create a pressure barrier that would stop more pebbles from accreting at the planet’s solid surface. And as such, the planet should have been much smaller in size. However, the concentration of heavy metals found in such solid bodies that serve as the raw material for planet formation is much higher on Jupiter’s rocky core, which puts a doubt on the pebble formation theory.
As part of a new study, scientists studied the distribution of heavy elements on Jupiter and found that its chemistry is not uniform. In fact, the inner envelope has a higher percentage of heavy elements compared to the outer layer, which suggests that somehow, the inner layer continued to amass heavy elements as the planet was still in the early stages of its formation. The paper, which has been published in Astronomy & Astrophysics, notes that planetesimals – tiny planet-like bodies that can span a few miles in size – played a key role in the formation of Jupiter’s inner parts. Existing theories claim that Jupiter grew by accreting small pebbles, and soon, it grew so big that it started pulling gas from its surroundings to form its windy atmosphere. Hower, the latest study claims that it was not just tiny space rocks that played a role in the formation of the gas giant.
Baby Jupiter Feasted On Baby Planets
“We know that once a baby planet is big enough, it starts pushing out pebbles. The richness of metals inside Jupiter that we see now is impossible to achieve before that. So we can exclude the scenario with only pebbles as solids during Jupiter’s formation. Planetesimals are too big to be blocked, so they must have played a role,” study lead Yamila Miguel was quoted as saying. Since Jupiter’s dense clouds obscure the view of the planet’s solid surface, the team relied on gravitational data collected by the Juno probe and found an unusually high concentration of metals heavier than hydrogen and helium.
Anywhere between 3 to 9 percent of Jupiter’s mass – which comes in at nearly 11 to 30 Earth masses – is made up of these heavy elements, which is a lot higher than previously expected. The pebble accretion model for Jupiter’s formation cannot produce such a high concentration of heavy elements. Thanks to computer modeling, the team observed that the gravitational pull around the planetesimals, which are much larger than the space pebbles mentioned above, would have allowed them to pierce the pressure shield created by the gaseous envelope, letting Jupiter to grow in mass and size while simultaneously building its gaseous atmosphere.