Fastest space “magnetic propeller” discovered

Scientists from the Universities of Sheffield and Warwick have discovered a white dwarf rotating at record speed in their opinion, it is the fastest rotating white dwarf discovered so far. This object makes a complete revolution in a record 25 seconds. The discovery is reported in a press release on

Scientists have established the rotation period of a star for the first time, confirming that this is an extremely rare example of a system with a “magnetic propeller”: a white dwarf pulls gas plasma from a nearby star companion and throws it into space at a speed of about three thousand kilometers per second. It is the second magnetic propeller discovered in more than 70 years.

The star, named LAMOST J024048.51 + 195226.9 (J0240 + 1952), is the size of Earth, but 200,000 times more massive. The plasma it pulls from its companion has in the past hit the equator at high speed, providing the energy for the dwarf to spin quickly. However, at some point, the white dwarf developed a strong magnetic field that causes most of the plasma to be repelled from the star into space. The rest flows to the magnetic poles.

According to scientists, the rotation is so fast that the white dwarf must have a mass above average, so as not to fly apart.