The earth is farther away from the sun

Each year the distance between the sun and the earth increases by 15 cm. The momentum of the sun's decline may be the cause of this phenomenon.

The distance between the earth and the sun increases by 15 cm every year.

Astronomers love to measure the distance between the sun and the earth for thousands of years. In the third century BC, Aristarchus of Samos - the first astronomer to mention heliocentrism - thought that the distance between the sun and the earth was 20 times the distance between the earth and the moon. His calculations were inaccurate, because the actual number was then 400.

At the end of the 20th century, the measurement of distance in the universe became more convenient and unified thanks to the advent of astronomical units. Thanks to the radar wave technique (broadcast to the celestial bodies and receive the echo signal, then calculate the distance by taking time multiplied by the wave velocity), the distance between the sun was calculated. and the earth with considerable accuracy. Currently the distance is 149,597,870,696 m.

That exact number allowed Gregoriy A. Krasinsky and Victor A. Brumberg - two Russian dynamics experts - to discover that the sun and the earth are getting farther apart. The level of increase is not large - only 15 cm per year - but what is the problem that caused that phenomenon?

One explanation is: The sun has lost a significant amount of material due to fusion and solar wind, so its gravity has decreased. Many scientists believe that the expansion of the universe, the effect of the black hole and the change of gravitational constant G are the cause. However, no hypothesis has been widely accepted.

Now four scientists from Hirosaki University (Japan) claim they have found the answer. In an article published in Europe's Astronomy & Astrophysics magazine, they thought that the earth and the sun pushed each other due to their tidal interactions.

Gravity from the moon causes tidal phenomena on our oceans. Thanks to a mechanism that the moon's orbit annually extends about 4 cm, while the earth's rotation speed decreases 0.000017 seconds.

The Japanese team thinks that gravity from Earth, Mars, Venus and other solar planets also causes similar effects on the sun. Because the sun does not have water, the tide does not happen. Instead its physical layers escape into space. According to their calculations, due to the impact of the earth, the sun's rotation speed decreases 0.00003 seconds per year. Thus, the distance between the sun and the earth increases as the sun is losing angular momentum.