Silent Explosion: The Faintest Supernova in the Galaxy ⚡ экспресс
Original: "Absence of Radio Emission Reveals an Exceptionally Weak Explosion of the Putative Historical Supernova Pa 30"
Nebula Pa 30 emits a thousand times fewer radio waves than expected — the quietest supernova remnant.
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Imagine a cosmic explosion that’s almost silent. Nebula Pa 30 was likely born in 1181, but modern radio telescopes pick up only silence. If it's a supernova, it's the faintest one known. The discovery hints that the Galaxy is full of unnoticed "ghosts."
🎯 Pa 30 is one of the few nebulae that can be linked to historical records: its outburst was observed in 1181 in the constellation Cassiopeia, and it hung in the sky for nearly half a year.
E_{\text{кин}} \lesssim 3\times 10^{47} \left( \frac{B}{10\,\mu\text{G}} \right)^{-1.65} \text{эрг}
Upper limit of supernova kinetic energy: E_kin depends on magnetic field strength B. For a typical field of 10 microgauss, the energy is less than 3×10^47 erg.