Astronomical research

A busy cluster of stars is hurtling at high speed as researchers try to solve the mysteries of space. The strange star cluster is called Terzan 5.

Professor Mark Krumholz from the Research School of Astronomy and Astrophysics, Australian National University (ANU) said that the strangeness of this star allows people to study the behavior of cosmic rays, which was reported from The Conversation.

Cosmic rays are high-energy particles that have random paths in space. The behavior of these rays has puzzled astronomers since they first discovered them in 1912, more than 100 years ago.

What was the last discovery from observing cosmic rays?

That mysterious radiation is Cosmic Rays

The existence of cosmic rays is inconceivable. When radioactivity was first discovered in the 1890s, scientists thought that every source of radiation on Earth was there.

However, in 1912, Austrian-American physicist Victor Hess measured ambient radiation levels in hot air balloons and found them to be much higher than at ground level, even during solar eclipses.

This means that the mysterious radiation comes from outer space. And now we also know that this mysterious radiation discovered by Hess is cosmic rays.

Cosmic rays are atomic nuclei and small particles such as protons and electrons that have been accelerated to nearly the speed of light.

These particles move through interstellar space. Because of their extremely high energy, a small fraction of cosmic rays can enter the atmosphere, as Hess discovered.

The problem of measuring the propagation speed of cosmic rays

The magnetic tissue effect became the basic technology for CRT monitors and old televisions. This technology uses this effect to direct electrons to the screen, so they can create an image.

Interstellar space is filled with constantly changing magnetic fields. As a result, cosmic rays bend in different random directions, just like the CRT on an old, broken television displays static on its screen.

Cosmic rays are cut by particles. This means that the direction of motion can change when it encounters a magnetic field.

These variable cosmic rays make it difficult to measure how fast they spread throughout the galaxy. At the same time on Earth, the rays are almost the same from all directions in the sky.

Because of Terzan 5, we can measure magnetic fluctuations

Terzan 5 is a cluster of stars that emits an abundance of cosmic rays. Because this star cluster consists of a large population of rapidly rotating, very dense and magnetized stars, known as millisecond pulsars.

By monitoring the radiation produced by cosmic rays on Terzan 5, researchers achieved an important scientific achievement. Krumholz said that his research team succeeded in measuring the speed at which these particles change direction due to variations in the interstellar magnetic field.

These cosmic rays do not reach the Earth because of the changing magnetic field. However, we still see signs of cosmic rays.

A sign of the appearance of cosmic rays is that some of them collide with photons of starlight, turning them into zero-energy and high-energy particles. These particles are called gamma rays.

Gamma rays move in the same direction as the cosmic rays that produce them. However, magnetic fields are not removed from gamma rays. Gamma rays can travel in straight lines and reach the Earth.

The cosmic rays that launched the Terzan 5 group first traveled on the tail. Gamma rays are not produced by these cosmic rays because their tails are not aimed directly at us, but away from us. From here magnetic fluctuations arise.

However, there are so many cosmic rays pointing our way, even gamma rays are bright enough to see. We also know that they have traveled 30 light years along the magnetic tail of the cluster.

Eventually people were able to measure the time it takes for magnetic fluctuations to change the direction of cosmic rays. The findings, published in the journal Nature Astronomy by Krumholz and colleagues, reveal how the interstellar magnetic field works and where its fluctuations come from.

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