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3I/ATLASEvidence
Evidence · 3I/ATLAS

Amorphous silicates, closer to interstellar dust

JWST/MIRI found the dust's silicates amorphous and pyroxene-rich with no measurable crystalline fraction (below 5.3 per cent), unlike Solar System comets and closer to interstellar dust.

Suggestive0

What it means

Answer this evidence bears onAn icy body from a cold, metal-poor disc around an old star
Supports6 for, none against
Still possibleunchanged
What it implies
  1. Its dust was never heated enough to crystallise, so it formed far from its star or in a disc with little radial mixing.For the key question: What is 3I/ATLAS made of, and why is its chemistry so unlike a Solar System comet's?

Next steps 2

1
Compare gas lost with crust depth
Could shiftFair odds~20 h
11score
Details

Use the compiled production rates (Frincke and Seligman's table) to date when more than 20 m of surface had gone, and check whether the composition changed then. A change at that point favours the crust; a change well before or after weakens it.

2
Test whether a cosmic-ray crust can raise D/H to 1 per cent
Could shiftFair odds~30 h
8score
Details

Run the cosmic-ray processing model forward to predict how much a 20-m processed crust changes water D/H and 12C/13C. If processing cannot reach the measured ratios, the birthplace reading is strengthened; if it can, the isotopes no longer date the body.

Ranked by how likely each is to move the key question, for the time it takes

Sources 2

Cite it

Mysteries Department. (2026). Amorphous silicates, closer to interstellar dust [Evidence EVD0DFQ3TYE9F15]. https://mysteriesdept.com/r/EVD0DFQ3TYE9F15
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