a neutron star PSR J1748 2446ad, the fastest confirmed spinning pulsar known: it spin 716 times every second.

 

Imagine compressing more than a star’s worth of matter into something roughly the size of a city.

Now make it spin 716 times every second.

That object actually exists.

It is called PSR J1748 2446ad, a neutron star discovered in the globular cluster Terzan 5. Since its discovery in 2006, it has remained the fastest confirmed spinning pulsar known.

One complete rotation takes only about 1.4 milliseconds.

That works out to nearly 43,000 revolutions per minute.

For comparison, Earth needs 24 hours to rotate once.

A neutron star is what can remain after the core of a massive star collapses. Gravity crushes an extraordinary amount of matter into a sphere only a few tens of kilometres across, creating densities so extreme that a tiny amount of neutron star material would contain an enormous mass by everyday standards.

For PSR J1748 2446ad, its rapid rotation places an important constraint on its size. Depending on its mass and the physics of ultra dense matter, its radius must remain small enough for gravity to prevent the star from tearing itself apart.

If its radius were close to 16 kilometres, material around its equator would be moving at roughly one quarter of the speed of light.

Yet the star remains intact.

There is a limit, however. Spin a neutron star fast enough and centrifugal effects would eventually overcome gravity at the equator, causing matter to be shed into space. Theoretical calculations suggest neutron stars could potentially rotate even faster than this record holder.

So 716 rotations per second may not even represent nature’s absolute limit.

Somewhere in the Galaxy, an even faster one may still be waiting to be found.

Astronomy Wonders