The sun is bigger according to a new study – the facts are changing

Despite the insistence of physicists and the ease of calculations, celestial bodies are not perfect spheres. Their surfaces may be rough or their boundaries blurred. As for the stars, what we know is S sun It seems we don’t know it as well as we thought, as different ways of measuring its size don’t quite agree on a single number.

The officially accepted radius of the Sun is 695,700 kilometres, according to The Guardian. IFL Science In his related publications. This was determined in 2015 by the International Astronomical Union and is calculated by observing the photosphere, the deepest layer of the Sun’s atmosphere, which we usually consider to be the surface of the Sun and is therefore used in various scientific models.

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What a new study has shown about the sun

But this is not the only way to measure the size of the Sun. Researchers have used completely different methods to estimate the size of our star, as in the new study published in Monthly Notices of the Royal Astronomical SocietyThere is a slight difference: the authors believe that the radius of the Sun is somewhat larger than the radius of the official photosphere.

Researchers from the University of Tokyo and the Institute of Astronomy, respectively, applied astroseismology to the Sun. They tracked the wave motion inside our star, and actual solar oscillations. These oscillations are known with such precision that they can be used to estimate the Sun’s general properties, including its size.

Sound waves, called f waves, have been used in the past to estimate radius. These waves are very close to the surface, and using them, the researchers found a value different from the photosphere estimates. In the new study, the researchers looked at p waves, which are waves that permeate the entire sun, including its core.

“It’s a different way. I wouldn’t say it’s better. It has some advantages and disadvantages. The p-waves are sound waves and they propagate directly through the sun. So they actually give a measurement of the entire sun. Whereas the f-wave is a surface wave and it measures the surface layers,” the professor said. Douglas Gough told IFL Science when asked about choosing this method to estimate the size of the Sun.

The study found that the Sun’s radius is 695,780 km, which is about 80 km larger than the official record. The difference is small, but important in terms of the high-resolution analyzes we perform of the Sun and beyond. In fact, it would mean that the current model of the Sun we have is not accurate and therefore correct.

“Sound waves measure things deeper. They give you a measurement of the radius of the Sun as seen from inside the Sun, not from the outside – if you will – and that’s the difference. So there are two different measurements,” Professor Douglas Gough explained to IFL Science.

The role of the solar cycle

However, why wavelength and optical methods give different results is currently unclear. One possibility that the researchers in this study would like to investigate relates to the solar cycle, that is, the change in activity that our star shows every 11 years.

In detail, it is possible that the cycle affects the surface of the Sun and its brightness more, and thus the measurements of the f-wave in the photosphere also change. But it is also possible that this is a deeper phenomenon and that p waves are also affected, so differences may have to be found elsewhere.

There’s a lot going on in the Sun, and we don’t fully understand our solar system’s star. This study confirms that more research is needed to solve many of the mysteries surrounding the Sun, but small changes in radius may impact other fields outside astronomy.

For example, solar neutrinos come from the core of the Sun and provide information for nuclear physics. However, their number is very sensitive and is related to the size of the Sun. If the Sun were slightly larger or smaller, the flux would be correspondingly larger or smaller – a very important element in many theories.