Comet 3I/ATLAS: NASA Telescope Reveals Unusual Activity

Hear’s a ⁣breakdown of the key information from ‍the provided text, focusing⁣ on how the TESS telescope was used to study⁢ interstellar comet 3I/ATLAS:

TESS’s Primary Function: The⁢ Transiting Exoplanet Survey Satellite (TESS) is designed to detect exoplanets by observing stars for dips in brightness as planets pass in front of them.
Unexpected Data Source: researchers realized TESS had data on interstellar ⁢comet 3I/ATLAS as the telescope was pointed in⁣ that direction around the time the comet was predicted⁣ to be ther. They went back through TESS’s⁣ archives.
Data⁢ collection Period: They found data from May 7th, 2025, to June 2nd, 2025.
“Shift-Stacking” Technique: As 3I/ATLAS moves faster than the stars⁣ TESS usually observes, a special technique called “shift-stacking” was needed. This involved:

Predicting the comet’s⁤ position in ‍each image.
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Shifting the images to align the comet.
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stacking the images together to create a clearer⁣ signal.
Comet’s movement & Brightness: The comet moved ⁣from ⁤about 6.35⁣ AU to 5.47 AU during the⁣ observation ‍period. Its brightness increased by a factor of 5,⁤ more than expected based on distance alone. Clarification for Brightness Increase: Researchers believe the⁣ increased brightness is due⁤ to the comet releasing “hypervolatile” materials (like ⁣carbon‍ dioxide and carbon monoxide)‍ -⁣ substances‍ that sublimate (turn into⁤ gas) at⁤ higher temperatures than water ice. This is unusual because comets in our solar system have ⁤largely depleted these materials.
Speculation & Option Theories: There was initial speculation about the comet’s behavior, including the possibility of ‍it being alien technology, but the researchers favor the outgassing explanation.