I've always loved our solar system, particularly facts about the sun! Its sheer size and temperature are enough to leave you in awe but there are plenty of other reasons to find the star that heats the earth, interesting, frightening and beautiful all at the same time. Here are some fun facts about the sun - hopefully you learn something new!
1. It's Huge
One of the many interesting facts about the Sun is that it's massive. If you think the earth is big, relative to the Sun it's just a speck - about 1.3 million earths could fit into the Sun. The Sun consists of 98% of the total mass of the solar system with Jupiter filling the majority of the rest. That leaves less than 1% mass for all the other planets! The Solar System consists of more than 100 billion stars and our Sun is in the top 10% by mass. In relation to the universe however, the Sun is considered a medium-sized star. Its diameter is 1,390,000 km across and its mass is a whopping 1.98892 X 10^30 kg - That's quite a few zeros! To put it into perspective, the Sun is 333,000 times the mass of the earth.
2. It's Incredibly Hot
The temperature of the Sun varies significantly. At the core, where extreme pressure, temperature and nuclear fusion happens, the temperature can reach up to 27 million degrees F (15 million degrees C)! As energy moves outward towards the Sun's surface, the temperature begins to drop. The upper layer of the Sun's interior dips below 3.5 million degrees F (2 million degrees C) and once the energy reaches the outer "layer", the photosphere, the temperature is approximately 10,000 degrees F (5,500 degrees C). At this point, the sun's radiation is detected as as sunlight. The next layer of the Sun's atmosphere is called the chromosphere which is cooler still at about 7,800 degrees F (4,000 degrees C). Even odder, a plasma region around the Sun, called the corona that extends over 1 million km from its surface, reaches up to 3.5 million degrees F (2 million degrees C). It's crazy to think about all the different temperature zones the Sun has!
3. It Causes the Northern Lights
Solar wind, originating in the Corona of the Sun, causes solar flares of extremely charged particles to blow through Earth's ionosphere, interacting with our own magnetic field. This interaction causes the gorgeous Northern Lights or Aurora Borealis, that display beautiful flares of colored light. It also happens in the southern hemisphere known as Aurora Australis. I know I want to witness this spectacular site at least once in my lifetime!
4. We Wouldn't Be Here without It
The Sun's energy and power is the fusion of hydrogen atoms into helium. The perfect warmth and luminosity of the sun that allows life to be sustained on earth, is technically the loss of Sun's mass. The Sun's energy is vital for plant life (photosynthesis) which produces the oxygen that you and I breathe. Not only that, the Sun's gravitational pull is what holds the Solar System in orbit, obviously including Earth. Without the Sun, we wouldn't be here!
5. It's Not Completely Solid
Similar to gas planets like Jupiter and Saturn, the Sun has a solid core and a fluid body consisting of hydrogen and helium. The equator of the Sun completely rotates once every 25.4 days and then at the poles, it rotates at much as once every 38 days. Because it's not a solid body, it behaves in this odd manner of changing rotation and even extends down quite a ways into the core where it's solid. The solid mass of the core, where fusion of hydrogen happens, rotates together as a whole like the Earth.
6. It Has 5 Billion Years of "Life" Left
The Sun formed first within our solar system, but not by much. In essence, the Sun consists of the fusion of hydrogen and helium which fuels it's extreme power. Each second, 700,000,000 tons of hydrogen are converted to 695,000,000 tons of helium and 5,000,000 tons of energy (gamma rays). By the time that energy reaches the surface of the sun, it's mainly visible light. The Sun has been burning for about 4.5 billion years and has enough hydrogen left in its core to keep burning and radiating energy for another 5 billion years. At that time, the Earth will be totally destroyed!
7. It Takes Only Minutes for the Sun's Light to Reach Us
The Sun is about 150 million km from Earth and its light from the surface travels at 300,000 kilometers per second. With that information, it gives only about 8 minutes for the Sun's light energy to reach Earth! More interesting still, the fusion energy at the Sun's core has already taken millions of years to reach its surface - what a long and very fascinating process from our awesome Sun!
When you really think about the conditions of the Solar System and how the Sun is literally holds all of life together, it's enough to leave you stunned. The sun is big but not too big; it's hot but not too hot; it's definitely not dull but just bright enough. It's amazing to think about all the conditions that allow our Sun to support life on earth. Hopefully you learned something about our life-supporting star we call the Sun! What other facts about the Sun can you share with us? Have you been inspired to learn more about the universe we live in?