T he S un's V ital S tatistics The Sun is a rather commonplace celestial object. It is a star of ordinary dimensions and of ordinary brightness. But to observers on the Earth, the Sun remains an object of magnificent proportions. This fiery ball of superheated hydrogen and helium gases contains 99.9 percent of all matter in the Solar System, and a million Earths could fit inside the Sun, with room to spare. On this page, we present some of the Sun's vital statistics. We think that you might be impressed with our magnificent star too. Age At least 4.5 billion years, in present state. Distance Mean distance from Earth 1.5 X 10^8 km Variation in distance through the year +/- 1.5 percent Diameter 1.39 X 10^6 km (or 109 times the diameter of the Earth and 9.75 times the diameter of Jupiter) Volume 1.41 X 10^33 cm^3 (or 1.3 million times the volume of the Earth) Mass 1.99 X 10^30 kg (or 333,000 times the weight of the Earth) Magnetic Field Strengths (typical): Sunspots 3000 G Polar Field 1 G Bright, chromospheric network 25 G Emphemeral (unipolar) active regions 20 G Chromospheric plages 200 G Prominences 10 to 100 G Earth 0.7 G at pole Chemical composition of photosphere

(by weight, in percent): Hydrogen 73.46 Helium 24.85 Oxygen 0.77 Carbon 0.29 Iron 0.16 Neon 0.12 Nitrogen 0.09 Silicon 0.07 Magnesium 0.05 Sulfur 0.10 Density (water=1): Mean density of entire Sun 1.41 g/cm^3 Interior (center of the Sun) 160 g/cm^3 Surface (photosphere) 10^{-9} g/cm^3 Chromosphere 10^{-12} g/cm^3 Low corona 10^{-16} g/cm^3 Sea level atmosphere of Earth 10^{-3} g/cm^3 Solar radiation: Entire Sun 3.83 X 10^23 kW Unit area of surface of Sun 6.29 X 10^4 kW/m^2 Received at top of Earth's atmosphere 0.136 W/cm^2 Surface brightness of the Sun (photosphere): Compared to full Moon 398,000 times Compared to inner corona 300,000 times Compared to outer corona 10^10 times Compared to daytime sky on Pikes Peak 100,000 times Compared to daytime sky at Orange, NJ 1000 times Temperature: Interior (center) 15,000,000 K Surface (effective) of Sun 5800 K Sunspot umbra (typical) 4240 K Penumbra (typical) 5680 K Chromosphere 4300 to 50,000 K Corona 800,000 to 3,000,000 K Rotation (as seen from the Earth): Of solar equator 26.8 days At solar latitude 30 deg 28.2 days At solar latitude 60 deg 30.8 days At solar latitude 75 deg 31.8 days Source of these numbers are from the book: A New Sun: The Solar Results From Skylab, by John Eddy, NASA SP-402, 1979, page 37. The effective solar temperature came from Lang's Astrophysical Quantities, pg. 162, 1964. Another Internet site with a smaller "stats" table, but a nice overview of the important features of the Sun, can be found at Calvin Hamilton's Views of the Solar System: Sun. Home · Request Solar Posters · Site Map · Glossary · About Us · Contact Us ©2008 by Stanford SOLAR Center · Permitted Uses · Credits