NASAさんのインスタグラム写真 - (NASAInstagram)「Shine bright like a diamond – or should we say, like our lovely home star, the Sun! ☀️ This week’s Saturday Science is all about our Sun. The Sun is located 93 million miles away from Earth. If we were closer to the Sun, our planet would be too hot to live on! Like most stars, the Sun is a giant ball of hot gas with a scorching core of 27 million degrees Fahrenheit. It's is also actually on the small side, as far as stars go - though it seems gigantic from our perspective (109 times wider than Earth!). The Sun is the center of everything that happens in our solar system – literally and figuratively. For starters, the Sun’s gravity keeps all the planets in orbit, including Earth. Sunlight powers much of life on Earth, providing energy for photosynthesis, which is how plants use sunlight to generate oxygen and sugars. The Sun powers our water cycle and helps us stay warm, tell time, and enjoy those summer days on the beach. Sunlight comes in visible and invisible wavelengths. Visible light is the bright light we can see. Invisible light includes radio waves, microwaves, X-rays, gamma rays, infrared, and ultraviolet (UV) radiation. UV-B, a type of ultraviolet radiation, can cause painful sunburns. However, you can combat these harmful rays by using sunscreen. So next time you do enjoy a hot summer day, lather up! Heliophysics, the study of the Sun, is an important area of study for NASA. In fact, in 2023 and 2024, @nasasolarsystem is celebrating the Heliophysics Big Year by spotlighting two solar eclipses. Solar eclipses happen when the Moon slides between the Sun and Earth when the Moon is at or near its farthest point from Earth. October 14, 2023 will kick things off with an annular solar eclipse. You can expect to see a “ring of fire” around the Sun during an annular eclipse. And on April 8, 2024, there will be a total solar eclipse, where the Moon will block the entire Sun, revealing the Sun’s ghostly white outer atmosphere. NASA will use these eclipses to study the Sun – and get the rest of us excited about our star, too! Want to get connected with the Sun? Check the link in our bio for more information and activities! (Image descriptions in comments)」7月2日 3時00分