Helium nova V445 Puppis ejects unprecedented high‑speed gas bullets

Astronomers have observed a rare helium nova, V445 Puppis, in the Milky Way after a surrounding dust cloud cleared. The blow‑out revealed clumps of oxygen‑rich gas described as “bullets” travelling at up to 20 million miles per hour – a phenomenon not previously seen in any nova.

The nova, a white dwarf accreting material from an extremely rare helium star, erupted in late 2000 and launched an outflow that now spans more than a trillion miles. With the dust disc faded, researchers from the University of Warwick, including PhD student John Mills, confirmed the system’s nature and highlighted the mystery surrounding the origin of the bullets.