Our star, the Sun, continues to exhibit mysterious and cyclical behavior, much of which unfolds on its far side, hidden from direct view on Earth. Following an initial colossal eruption recorded by the LASCO/C3 coronagraph between October 21 and 22, 2025, two additional major Coronal Mass Ejections (CMEs) were subsequently detected. These powerful events, occurring with a remarkable regularity of approximately 24 hours between them, have generated an extraordinary situation in interplanetary space. All three eruptions were aimed directly at a rare celestial visitor to our solar system: the interstellar object 3I/ATLAS.
The initial CME, whose sheer scale underscores the Sun's immense power, was immediately projected toward the comet. Astronomers calculated that the front of superheated plasma would intercept 3I/ATLAS on October 24, engulfing the comet within the cloud of solar material for a duration of up to two days. However, the situation escalated dramatically when the subsequent two CMEs erupted in rapid succession, separated by roughly a day. This sequence of three powerful solar strikes constitutes an unprecedented bombardment.
Analysis of the second CME indicated a less direct hit. Based on its asymmetrical structure, scientists believe this second plasma wave was likely only to graze the comet, with the majority of the material passing to the north of the target. This offered a brief moment of potential reprieve for the interstellar body.
Any hope of avoiding further impacts was quickly dispelled by the third eruption. This final CME was precisely directed at 3I/ATLAS, confirming a distinct and clear cyclical pattern in the activity emanating from the hidden active region on the Sun's reverse side. This triple assault ensures that the interstellar object will experience a prolonged and intense interaction with solar plasma.
The principal actors in this cosmic drama are the Sun and comet 3I/ATLAS. While the comet is currently enduring a genuine “coronal storm,” terrestrial safety remains assured. Crucially, all three massive ejections were directed away from our planet, meaning Earth is completely protected from this intense solar activity.
The interstellar object 3I/ATLAS is a substantial body. Estimates place the diameter of its core at approximately 5.6 kilometers, giving it an estimated mass of 33 billion tons. This massive structure has already experienced a prior collision with solar plasma late in September. That earlier event marked a historic milestone: the first ever recorded interaction between a solar CME and material originating from outside the confines of the Solar System.
Observations stemming from that initial encounter, which included data gathered by the James Webb Space Telescope (JWST), revealed significant effects. The plasma impact temporarily distorted the comet’s tail and potentially triggered an anomalous release of carbon dioxide gas. The current triple strike is expected to yield even more dramatic results.
For the scientific community, this sequence of events represents an unparalleled natural experiment. The interaction between the Sun’s powerful energy and matter imported from the depths of the Galaxy offers a unique opportunity to unlock new secrets regarding both the behavior of solar activity and the fundamental composition of interstellar material.