Astronomers of the University of California in Los Angeles disclosed the riddle of the duration of the day on Venus, whose rotation period did not succeed for a long time, and the tilt of its axis and the size of the kernel. Scientists submitted their findings in the article published in the Nature Astronomy magazine.
New radar measurements held from 2006 to 2020 show that on average, the day on Venus lasts 243,0226 terrestrial days, which approximately corresponds to the two thirds of the earth. In this case, the speed of rotation of Venus always changes: a new dimension will give a result that will be slightly larger or less than the previous one. The difference is at least 20 minutes. This explains the strange differences in past measurements.
The reason is most likely the heavy atmosphere of Venus, which exchanges pulses with the surface of the planet. On Earth, a similar process leads to a change in the duration of the day for only a millisecond. On the second planet from the Sun, the mass of the atmosphere is 93 times more than the earth.
The angle of the axis of the venera is equal to exactly 2.6392 degrees (the land is tilted about 23 degrees), which is ten times higher than the accuracy of previous estimates. The cycle of precession axis takes 29 thousand years. Based on this data, the team calculated that the core of the planet is about 3,500 kilometers in the diameter, although it is not yet known, it is liquid or solid.