The only problem with this question is the verb tense. The impacts that our solar system will experience from the Scholz’s Star Oort Cloud encounter haven’t yet occurred, but they could well be significant.
Allow me to provide some background: Scholz’s Star, officially designated as WISE J072003.20−084651.2,* is a dim binary system with a red dwarf primary and a brown dwarf companion with a combined mass of 0.15 solar masses. Although the system is now 22 light years from the Sun, it passed relatively close to the Sun about 80,000 years ago. Although mathematical simulations of the close encounter yield only approximations, a research paper published in 2022 by Raúl de la Fuente Marcos and Carlos de la Fuente Marcos indicated that there is a 90% probability that Scholz’s Star came within 0.317 – 0.345 parsecs (65,385 – 71,160 AU) of the Sun between 78,600 – 81,100 years ago, with the most likely value being 79,900 years ago.
Scholz’s Star. A dim binary system consisting of a primary red dwarf and a brown dwarf companion which is about 65 times as massive as Jupiter. Although this binary system is now 22 light years away, it passed through the Sun’s Oort Cloud about 70,000 years ago. Scholz’s Star is the cental reddish dot within the above photograph. Image credit: ESO VPHAS+
Initially, it was belived that Scholz’s Star would have had a negligible effect on Oort Cloud Comets. A paper published in 2015 entitled “The Closest Known Flyby of a Star to the Solar System” stated that there was a 98% probability that Scholz’s Star would have infilitrated the outer Oort Cloud, but a less than 0.1% probability that it penetrated the more dynamically active inner Oort Cloud, which is less than 20,000 AU from the Sun.
However, a 2018 paper published in the Monthly Notices of the Royal Astronomical Society entitled “Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies” indicated that a subset of 340 comets with hyperbolic orbits -consistent with those of Oort Cloud origins- were gravitationally influenced by Scholz’s Star. The implication is that Scholz’s star likely exerted more of an influence on the Oort Cloud than previously believed and so it might well have dislodged quite a few of its cometary nuclei.
All the same, we cannot expect to see any noticable increase in cometary apparitions as a result of Scholz’s passage because any disturbed comet will require at least a million years to travel toward the inner solar system. We should note Kepler’s 2nd law which tells us that an orbiting body’s velocity decreases with increasing distance from its parent body (the Sun). Consequently, any perturbed Oort Cloud nuclei will still be moving quite lethargically.
Let’s examine Halley’s Comet for a comparison. It reached aphelion in December 2023 and is now moving inexorably toward perihelion, which it will reach on July 28, 2061. Presently, at this moment (August 15, 2026), Halley’s Comet is only 35.9 AU from the Sun and will still need almost 35 years to reach its closest point to the Sun. Moreover, Halley’s current speed of 1 km/sec is comparatively breakneck compared to the much more distant Oort Cloud.
One of the most compelling aspects of night sky watching to me is to realize that an armada of approaching comets is concealed within the darkness between the stars. How many are currently en route and how many will affect Earth is currently unknown. However, we can be assured that at least some of those advancing comets were sent careening toward us by a star that happened by about 80,000 years ago.
*Wide-field Infrared Survey Explorer. The numbers indicate the star’s celestial coordinates with right ascension first followed by declination.
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