Researchers Think They've Found a "Strange Star" in Space

 

(Pobytov/Getty Images)

The small object XMMU J173203.3-344518 is undoubtedly amazing, packing around three-quarters of the mass of our Sun into a ball large enough to fit within Manhattan. strange, even. Maybe strange.

Is it odd, though? According to a recent study by physicists at the Federal University of ABC and the University of So Paulo in Brazil, this mind-bogglingly dense ball of star material may be weird after all, but perhaps not in the way you might expect.

 

The distance between Earth and the tiny star-crasher HESS J1731-347 was recalculated last year by scientists from the Institute for Astronomy and Astrophysics at the University of Tübingen in Germany.

 

The updated proximity was only 8,150 light-years distant, which was less than the earlier prediction of 10,000 light-years. Recalculating the compact object's attributes, particularly its size and mass, was necessary to account for the new distance.

That's when things started to get a little exciting.

 

A fraction of the stars' outer layers are blown away when stars of a certain mass collapse in a cosmic thunderclap of heat and electromagnetism when they run out of the kind of fuel that their gravity can expediently crush the daytimes out of.

All that is left is a dense object whose atoms are packed close together. Protons are forced to shed their charge and change into neutrons as a result of electrons being packed into their nuclei deep inside the object's core. It's a baby neutron star; congrats.

 

If there is sufficient mass, all of the additional gravity overrides the weak nuclear forces and causes the matter to collapse into an unfathomable state, producing a black hole. But in what is known as a "white dwarf," there is not enough mass, and the atoms continue to coexist peacefully.

XMMU J173203.3-344518 isn't just a record-breaker; it's also baffling at 77 percent of a solar mass. Neutron stars shouldn't be that small.

Which suggests that it might not even be a neutron star. The researchers speculated that it was instead a phenomenon known as a weird star, which is primarily made up of particles called odd quarks. They left their conclusions for other researchers to consider.

 

This inquiry picked up where the last study left off, returning to the unusually small compact item within HESS J1731-347 and verifying its mass, radius, and surface temperature.

 

The scientists concluded that this odd small item still possesses all of the characteristics of a fictitious strange star after comparing their findings with equations for strange matter and theoretical models for their formation in supernovae.

Basic building blocks called quarks form trios to form baryons. The protons and neutrons found in nuclear matter are two of these groups' more well-known representatives.

Those bundles of quarky deliciousness can defy the forces holding them together to arrange into something less structured if you focus enough energy in any one place. If you apply enough pressure to this heated soup, its quarks may emerge as an entirely new type of substance known as, unsurprisingly, quark matter.

 

Quarks naturally occur in a wide range of shapes or flavours. Protons and neutrons are created when the flavours of "up" and "down" combine. Down quarks can change into up quarks under strong enough pressure, and up quarks can then change into a strange quark, a different flavour.

Though some models show quark matter often evolved right from the start of the collapse, it is still unclear exactly how a hyper compact object consisting mostly of weird quarks arises from a supernova.

 

Something allows this matter to predominate under quite unusual circumstances, releasing more energy during the collapse to shake off more mass than usual and leaving that surplus of quarks behind.

Reference: sciencealert.com