Two international teams zoned in on a potential answer to a decades-long mystery surrounding ephemeral cosmic X-rays.

"This discovery heralds a broader understanding of the diversity in massive stars' deaths and a need for deeper investigations into the whole landscape of stellar evolution."

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New observations support the idea that hot, diffuse threads of gas called cosmic filaments connect clusters of galaxies across the cosmos. That is the conclusion of Konstantinos Migkas at Leiden University and colleagues who say that their study strengthens the idea that much of the normal matter in the universe resides in these structures.