Our galaxy's massive gas halo is being "squeezed" and heated by our passing neighbor galaxies.
April 14, 2026
Original Paper
Temperature asymmetry in the Milky Way's hot circumgalactic medium induced by the Magellanic Clouds
arXiv · 2604.08652
The Takeaway
The southern half of the Milky Way's surrounding gas is 12% hotter than the north because the Magellanic Clouds are plowing through it like a piston. This reveals that the space surrounding our galaxy is a dynamic, turbulent mess rather than a calm, steady cloud.
From the abstract
The Milky Way is surrounded by a hot diffuse circumgalactic medium (CGM) with temperatures of millions of degrees. Recent X-ray observations with the eROSITA satellite discovered a significant temperature asymmetry of this hot CGM, with the southern hemisphere being on average hotter than the northern one by a relative difference of ${\Delta} T/T \approx 12\%$, where $T$ is averaged over the entire CGM. In this Letter, we investigate whether the passage of the Magellanic Clouds can be responsibl