Sun It might be a little smaller than we expected.
Researchers measuring the Sun use total solar eclipses to block out much of the sun’s light and provide a glimpse of the sun’s corona, or outer atmosphere. This method determined that the sun’s radius is approximately 432,468 miles (695,990 kilometers). Accepted as a standard since the 1970s.
But to truly understand the Sun’s physics and atmosphere, we need more precise measurements. The sun is always in motion, after all, it is a ball of fiery plasma that convects intensely, and waves are constantly propagating through its surface and its volume. In the 1990s, researchers who measured some of the oscillations caused by waves known as f-modes found that the Sun was 0.03% to 0.07% smaller than light-based eclipse methods would suggest. (Different studies returned slightly different values.)
Now, a new study measuring yet another type of solar wave oscillation known as p-mode confirms those studies from the 1990s were correct. This means that the Sun is slightly smaller than standard estimates. According to the study, which has not yet been peer-reviewed, was published in the Physics Preprint Database on October 17th. arXiv, the sun’s radius is about 432,337.6 miles (695,780 km). It is approximately 864,675.3 miles (1,391,560 kilometers) in diameter. Essentially, the researchers concluded that both the old f-mode data and the new p-mode measurements show similar sizes.
These numbers only differ by a few percentage points, but they are important. These waves and vibrations offer a glimpse into the sun’s nuclear reactions, chemical composition and fundamental structure, the study’s co-authors said. Douglas Goffsaid an astrophysicist at the University of Cambridge. new scientist.
Without the right radius, “we could reach misleading conclusions about subtle elements of the Sun’s internal structure.” william chaplina professor of astrophysics at the University of Birmingham, UK, who was not involved in the study, told New Scientist.
Understanding the Sun means that not only is it Earth’s most accessible star (a source of light and heat that makes life possible), but also that magnetic storms from the Sun’s surface can affect Earth’s communications. It is also important because NASA’s Parker Solar Probe is currently orbiting seven times closer to the Sun than any previous spacecraft to understand the solar wind, which brings charged particles into contact with Earth’s atmosphere.European Space Agency solar orbiterIt is also investigating the solar wind launched in 2020, and plans to take close-up images of the sun’s polar regions for the first time.