The largest neutron star of all time has an incomprehensible mass

Everything in space is inhumanly large, heavy and distant. The earth is an insignificant planet, the gigantic sun a modest star. Distances are measured in light years, as the cosmos is only somewhat manageable with the dizzying speed of light. Sometimes it almost seems like it’s on purpose. Anything to hammer home this one message: you, dear friends, are cosmically totally irrelevant.

That same feeling washes over you with the latest addition to the space record books, the one astronomers described this week. in the review Letters from the Astrophysical Journal: the most massive neutron star ever measured.

But neutron stars are already quite extreme phenomena. They form from massive stars when they die in a catastrophic explosion called a supernova. In this ultra-violent event, the remnant of such a star is compressed with unimaginable power. What remains is nothing like the ordinary: a single tablespoon of neutron star weighs as much as the whole of Mount Everest.

Neutron paste

To get a sense of these bizarre stars, some astronomers turn to — no, really — comparisons to Italian cuisine.

It already starts below the surface, where hundreds of neutrons close together form what are called “gnocchi”. Farther inward, where the pressure is higher, these become long strings. That’s right: neutron spaghetti. Deeper still, these volutes merge into a plane (neutron lasagna) until they form a uniform mass of holes, as if they contained elongated tubes: neutron penne, neutron bucatini or, if you prefer, the anti phase. -spaghetti. Right.

So much for the theory, now for the practice.

The star discovered by astronomers is called PSR J0952−0607 and is a so-called pulsar. That is to say: a neutron star which rotates like a kind of cosmic beacon and sends out radiation into the universe. This rotation spins at record speed, but more important is this other record: the star is about 2.35 times more massive than our sun. A mass that he collected by using his gravity to chew the material of his star partner, something that earned him the nickname “black widow”, named after the female spider who eats his partners.

The same particles as humans

Because physicists know that there is a point at which a neutron star can no longer withstand the pressure of its own gravity and then collapses into a black hole, it is useful to know where this upper limit is. Then you know how firmly the star supports itself, and that reveals something about the properties of this densely populated interior.

If PSR J0952−0607 is about the heaviest possible neutron star, then it consists of “ordinary” particles inside, the researchers write: neutrons and quarks up and down, for those in the know. The same particles that make up ordinary humans, planets and stars. But if a much heavier variant is discovered in the future, they could contain more exotic particles, which you can only find on Earth in particle accelerators.

And then say goodbye again, with that human touch.