Interstellar comets are the original cosmic explorers, and by studying their metallic whispers, we are learning the secrets of worlds we may never see directly.
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New infrared observations reveal that the rare interstellar visitor known as comet 3I/ATLAS has dramatically brightened during its farewell tour of the solar system.
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A new comet approaching the sun has caught the attention of astronomers, primarily because of its lineage. It appears to belong to a group of comets that in some cases have briefly become outstandingly bright objects.
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The comet broke into pieces after making a close approach around the sun in October 2025.

The interstellar visitor may still have a few things to tell us before it leaves our solar system.

C/2024 E1 (Wierzchos) brightened significantly ahead of its close approach to the sun.

3I/ATLAS is heading away from the sun on an escape trajectory from our solar system.

In late April 2026, a long-period comet will swing through the inner solar system. It will likely be visible with binoculars, and there’s a small chance it could be seen with the naked eye.
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