A new analysis of Hubble Space Telescope imagery of the interstellar object 3I/ATLAS reveals a startling feature: its sunward glow is ten times longer than its width. This unprecedented observation, co-authored by Avi Loeb and Eric Keto, directly contradicts the typical cometary behavior where tails point away from the sun. The elongated glow, appearing as an 'anti-tail,' is not simply a matter of perspective. Even accounting for the observational geometry, the sunward extension remains dramatically pronounced.
This remarkable elongation is attributed to the evaporation of ice fragments, unlike the dust particles usually responsible for cometary tails. These ice fragments, predominantly launched from the sun-facing side of 3I/ATLAS, survive longer in the sunward direction, creating this extreme aspect ratio. While alternative explanations are possible, the sheer scale of the elongation remains unparalleled in scientific literature.
The discovery adds to the already anomalous profile of 3I/ATLAS, raising questions about its composition and origin. Five key anomalies further distinguish this interstellar object:
1. **Retrograde Trajectory:** 3I/ATLAS's path is unusually aligned with the ecliptic plane, a statistically improbable coincidence.
2. **Massive Nucleus:** Its nucleus may be significantly larger and more massive than previously observed interstellar objects, potentially millions of times more massive than 2I/Borisov.
3. **Sunward Glow (Anti-tail):** The consistent observation of the elongated sunward glow for several months is a unique and previously undocumented phenomenon.
4. **Unusual Composition:** Analysis shows a distinct composition consisting primarily of carbon dioxide (CO2), with traces of carbon monoxide (CO) and water (H2O), along with unexpected elements like nickel (without iron) and cyanide.
5. **Anomalous Polarization:** 3I/ATLAS exhibits an extreme negative polarization unlike any other known comet, suggesting a unique interaction with sunlight.
These anomalies collectively challenge the traditional understanding of comets. The common assumption of a dusty, water-rich composition may not adequately explain the observed characteristics. Further investigation using ground-based and space-based telescopes is crucial as 3I/ATLAS continues its journey. This unique interstellar object presents an exceptional opportunity to expand our knowledge of the cosmos and potentially rewrite established scientific theories.
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Originally published at: https://avi-loeb.medium.com/the-sunward-glow-in-the-hubble-image-of-3i-atlas-is-ten-times-longer-than-it-is-wide-3a5cff257a94
