In about 90 percent of all tested scenarios, the outer solar system became unstable within three billion years after the white dwarf formed, according to new simulations. Research suggests that as the sun sheds mass during its final stages, irregular ejections may trigger chaotic planetary orbits, potentially ejecting giant planets into interstellar space within three billion years.
Planets Face Chaos from Irregular Mass Loss
For decades, astronomers operated under the assumption that the sun would lose mass in a steady, uniform manner as it evolved into a white dwarf. This traditional model suggested the outer planets—Jupiter, Saturn, Uranus, and Neptune—would gradually migrate to wider orbits, remaining stable for tens of billions of years. A new study published in The Astrophysical Journal Letters challenges this view by introducing the concept of stochastic, or random, mass loss.
The Solar System could fall apart much sooner than previously thoughthttps://t.co/X8Rkv2UgGg pic.twitter.com/B7WunlsQW4
Scientists of the California Institute of Technology have calculated that the outer solar system could fly apart in roughly a billion years after the death of the sun. The new study in The Astrophysical Journal Letters shows that unpredictable mass losses of the sun plunge the system into chaos far earlier than previously assumed.
Long ago, it was considered certain that our solar system would remain stable for the time being. Even if the sun sheds its outer layers in the distant future and shrinks into a white dwarf, the large planets should outlast it by billions of years.
A new scientific study now shows that our solar system could die much earlier than previously thought. In a few billion years, our sun will run out of hydrogen in its core, swell into a red giant and swallow Mercury and Venus in the process.
Whether Earth meets the same fate or barely survives as a scorched rock is something models disagree on. Under the influence of passing stars, scientists previously calculated 30 to 100 billion years.
Konstantin Batygin and his colleagues are now questioning this very assumption. Dying stars can apparently also shed their matter in individual, irregular bursts, causing the star to experience a small kick each time. Thousands of such shoves could gradually scramble the orbits of the planets circling far outside.
Simulations Reveal Rapid Instability
The team performed simulations to understand how these random mass-loss events affect planetary alignment. By assuming the sun ejects matter in individual events—each accounting for about 33 Earth masses—the scientists observed that the outer solar system’s stability is far more fragile than previously believed.
- In 37 cases, the orbits of the outer planets began to cross before the sun had even finished its transition into a white dwarf.
- In approximately 40 percent of simulations, the system experienced severe orbital scattering or total disruption during the sun’s red giant phase.
- In about 90 percent of all tested scenarios, the outer solar system became unstable within three billion years after the white dwarf formed.
Konstantin Batygin, an astrophysicist at Caltech and the study’s lead author, noted the significance of these findings. In nine of ten of our simulations, at least one giant planet is thrown into interstellar space,
Batygin told ScienceAlert regarding the fate of the outer planets. Batygin explained to ScienceAlert what happens when uniformity gives way to a granular structure.
Evidence Found in White Dwarfs
The hypothesis that dying stars experience asymmetric mass loss is supported by observations. Data from distant binary star systems containing white dwarfs indicate that these stars often receive a kick
after formation, which researchers attribute to uneven material ejections. This provides an indirect basis for applying similar physics to our own sun’s future.
Despite these findings, the researchers emphasize that these percentages are conditional results of a physical model rather than guaranteed future events. Whether our sun will produce ejections of the specific magnitude and frequency assumed in these simulations remains an open question. If these conditions are met, however, the solar system could experience orbital instability far sooner than the previous estimates that relied on the influence of passing stars. Further observations and more accurate models of stellar mass loss must show whether this scenario applies.
When the sun dies, it doesn’t just enlarge the planetary system it created. It shakes it and, in most cases, causes it to fall apart.
Batygin, Fuller, & Adams