Meet pulsars, the fastest spinning balls in the universe

*This text was written by a columnist. TecMundo; finally learn more.

Exploring the depths of space beyond our sky often means encountering magnificent objects and phenomena. Black holes, supernovas, planets raining diamonds… All this is presented by means we understand. CScience. One of these cosmic surprises is the fastest spinning object class in existence: pulsars.

Pulsars are neutron stars known for their ability to be denser than the nucleus of a uranium atom and have some of the strongest magnetic fields in the Universe. Also, these super-dense stars are only a few kilometers in diameter and yet have more mass than our entire Sun.

However, the most notable feature of a pulsar is that they are objects that spin extremely fast, reaching speeds of hundreds of times per second.

The discovery of the first pulsar (and, consequently, the existence of this category of celestial bodies) took place in 1967, and what we call coincidence in science can be said to be almost accidental.

The pulsars were discovered by British astrophysicist Jocelyn Bell Burnell while she was still a graduate student at Cambridge University and using the radio telescope developed by her and her advisor, British astronomer Antony Hewish, to search for quasars.

During his observations, Jocelyn confirmed the existence of a pulsed radio signal among the stars with a regularity of three pulses per second on graph papers.

This signal baffled him and the astronomers community at the time, as there was no known physical phenomenon in the universe that naturally produced this observation. For this reason, it was initially thought as a half-joking, half-serious and reasonable assumption that the signal had an artificial origin, the product of another civilization. Because of this, the object was tentatively named “Little Green Man 1”, Little Green Man 1.

Now officially known as PSRB1919+21, this object was identified a few years later as a rapidly spinning neutron star, the first pulsar detected.

Jocelyn’s discovery made a huge impact on the scientific community, and since then pulsars have been understood as essential objects for understanding the nature of stars, particularly the final stages of the lives of massive stars that produce exotic objects such as neutron stars and black. holes.

While Jocelyn is not recognized with the Nobel Prize in Physics for her achievement (it was given to her mentor for discovering pulsars), her discovery helped pave the way for women in science.

Although pulsars are called “neutron stars,” about 95% of their mass is actually neutrons. The remaining percentage is due to protons and electrons that are not crushed in the nuclei of atoms.

As the pulsar rotates, the charged particles that make up it move rapidly, creating a large magnetic field. When the surrounding particles enter this area, they accelerate and create a jet of radiation emanating from the poles of the neutron star. When one of these poles is pointed directly in our direction, we can detect the “pulse” of the pulsar.

Most neutron stars do not appear to us as pulsars because they are not aligned with our field of view. All neutron stars can be pulsars, and in any case we cannot observe that only a small fraction of them actually vibrate.

There are many different rotation periods among pulsars. The fastest spinning pulsar ever discovered is PSR J1748-2446ad, which spins at 716 Hz, or 716 times per second. This pulsar was discovered in 2004 and is located in a globular star cluster called Terzan 5, located about 18,000 light-years from Earth in the constellation Sagittarius. Its estimated radius is only 16 km, and its equator is spinning at around 24% the speed of light, or over 70,000 kilometers per second!

In fact, there are very few objects in the Universe that are completely at rest: almost everything we know rotates in some way. Every moon, planet and star we know rotates on its axis. Every binary pair, every galaxy, and even galaxy groups and clusters have rotational speeds. But none are as intriguing as pulsars, real cosmic peaks!

Nicolas Oliveiracolumnist TecMundoHe holds a diploma in Physics and a master’s degree in Astrophysics. Professor and currently doing his PhD working with galaxy clusters at the National Observatory. He has experience in Teaching Physics and Astronomy and researching Extragalactic Astrophysics and Cosmology. He works as a scientific dissector and communicator for the dissemination and democratization of science. Nicolas is found on social networks as: @nicooliveira_.