1. lies at the heart of the solar system the largest object of solar system 99.8 percent of the solar system's mass roughly 109 times the diameter of the Earth — about one million Earths could fit inside the sun. visible part of the sun is about 10,000 degrees Fahrenheit (5,500 degrees Celsius) temperatures in the core reach more than 27 million F (15 million C), driven by nuclear reactions. Week 5 Day 1 Sun

2. one of more than 100 billion stars in the Milky Way—our galaxy one of more than 100 billion stars in the Milky Way orbits some 25,000 light-years from the galactic core, completing a revolution once every 250 million years or so born about 4.6 billion years ago4.6 billion years ago Many scientists think the sun and the rest of the solar system formed from a giant, rotating cloud of gas and dust known as the solar nebula.giant, rotating cloud Sun

3. As the nebula collapsed because of its gravity, it spun faster and flattened into a disk. Most of the material was pulled toward the center to form the sun. The sun has enough nuclear fuel to stay much as it is now for another 5 billion years. After that, it will swell to become a red giant. Eventually, it will shed its outer layers, and the remaining core will collapse to become a white dwarf. Slowly, this will fade, to enter its final phase as a dim, cool theoretical object sometimes known as a black dwarf.red giantwhite dwarfblack dwarf Sun

4. The strength of the sun's magnetic field is typically only about twice as strong as Earth's field. it becomes highly concentrated in small areas, reaching up to 3,000 times stronger than usual. These kinks and twists in the magnetic field develop because the sun spins more rapidly at the equator than at the higher latitudes and because the inner parts of the sun rotate more quickly than the surface.kinks and twists Sun

5. These distortions create features ranging from sunspots to spectacular eruptions known as flares and coronal mass ejections. Flares are the most violent eruptions in the solar system, while coronal mass ejections are less violent but involve extraordinary amounts of matter — a single ejection can spout roughly 20 billion tons (18 billion metric tons) of matter into space. flarescoronal mass ejections Source (NASA) Sun

6. the tilt of the moon's axis is only about 1.5 degrees As such, the moon virtually has no seasons. This means that some areas are always lit by sunlight, and other places are perpetually draped in shadow. has a very thin atmosphere, so a layer of dust — or a footprint — can sit undisturbed for centuries.thin atmosphere without an atmosphere, heat is not held near the surface, so temperatures vary wildly (source NASA) Moon

7. Lunar Cycles