Physics Cosmic Scale

Our solar system isn't flying through space like a comet; it's actually wrapped in a bubble shaped like a giant, split croissant.

arXiv · March 16, 2026 · 2603.13088

M. Kornbleuth, M. Opher, J. F. Drake, M. Swisdak, Zhiyu Yin, K. Dialynas, Y. Chen, J. Giacalone, J. M. Sokół, M. Gkioulidou, I. Baliukin, V. Izmodenov, G. P. Zank

Why it matters

For decades, textbooks have depicted our solar system moving through space with a long, trailing tail like a comet. New simulations show that magnetic explosions are actually splitting our 'home bubble' into two distinct lobes, completely changing our view of our place in the galaxy.

From the abstract

The shape of the heliosphere, regarded as comet-like since the 1960s, has recently been the subject of intense debate in the last decade. There is disagreement whether the heliospheric tail extends to $\sim$10,000 au in a comet-like shape or if it is short ($\sim$400 au) with a split. Energetic neutral atom (ENA) maps from Cassini/INCA at energies from 5.2 to 13.5 keV revealed a global structure extending from the nose to the heliospheric tail known as the Belt whose origin has remained largely