Does the sun rotate

Does The Sun Rotate?

The sun, our closest star in the heart of our solar system, can sometimes be overlooked due to its ubiquity in our lives. It’s rising in the morning wakes us up and its setting signals end of day and beginning of rest. The giant white-hot ball of gas and plasma suspended in the middle of our solar system directs our lives in more ways than we consciously think about.

It warms our planet to just the right temperature to allow us and our ecosystems to exist and thrive, controls our seasons, facilitates plant growth, provides a warm summer day to enjoy a barbecue with family and friends, protects us from cosmic radiation, shapes our 24 hour day and plenty more.

But with all the obvious reasons why the sun is important to our existence, we often forget that it is an extremely powerful object with magnificent dynamics which make it what it is and gives it its life-supporting abilities. To answer the question of whether the sun rotates, it will be helpful to start with the smaller details about the sun’s creation and composition. Only after having a solid understanding of this will we be able to make sense of the sun’s patterns.

The Sun’s History

4.6 Billion years ago, a solar nebula formed the sun. This massive rotating cloud of dust and gas accumulated the most mass in the center due to gravity and coalesced materials around it to form a hot ball of gas. Its gravity managed to orchestrate the formation of the planets by pulling and pushing on the rest of the dust and gas from the collapsed cloud. 3 million years after its formation, the sun had managed to create a baby version of our solar system.

The Sun’s Composition

Sitting in the middle of a solar system 25,000 light years from the galactic center of the galaxy we call the Milky Way, the sun makes up 99.8% the mass of the solar system in which it resides. Planets, moons, and asteroids within the system make up only .2% of the solar system’s mass. Size wise, the sun can fit all the planets in our solar system—600 times! Not to mention it can wear a belt of at least 100 Earths long. The sheer size magnitude of the object’s mass is what generates the gravitational field to pull the planets to its center, keeping them in place and drive their rotation around the sun.

Chemically, the sun is made up of 91% Hydrogen, 8.9% Helium, and .1% Carbon, Nitrogen, and other heavier elements. What we experience as heat and light from the sun comes from a process called Thermonuclear Fusion in which the sun’s extreme gravitational pull and temperatures at the core (15 million degrees Celsius to be exact) fuse hydrogen atoms together to create helium. The process gives out a tremendous amount of electric energy, heat, light, and radiation.

The Sun’s Structure

Structurally the sun has 6 distinctive layers, each with varying gravitational pull and temperatures which increase from the surface towards the core. The top-most layer of the sun is called the corona. This area is characterized by hot streams of ionized gas with a wide variety of temperatures from 500,000 degrees Celsius to 5.9 million degrees Celsius.

We cannot see the corona with our naked eyes because the light emitted from it is in the ultraviolet range. Below the corona is the chromosphere which reaches up to 20,000 degrees Celsius and below it is the photosphere. The photosphere’s density is light enough that light emitted from the core’s fusion activity can escape. The sunlight we see emanates from this layer.

Scientist estimate that it takes a photon about 100,000 to 200,000 years to escape from the sun. If this is the case, the light we are seeing today on earth was not made from the core’s activity today, but rather, 200,000 years ago, when the first homo sapiens appeared on earth.

Under the photosphere is the convection zone which extends from above the radiative zone to the sun’s surface. This region is responsible for transporting the sun’s energy from the core to the surface by the process of convection through hot columns of gas. We can see the tops of the columns which make up the surface of the convection layer with telescopes.

Between the core and the convective zone is the radiative zone. In this region, energy from the core coming in as nuclear energy transforms into electromagnetic radiation and moves outwards.

At the center is the sun’s core is full of extreme conditions. With internal pressure that is 260 billion times of ours here on earth and temperatures of up to 15 million degrees Celsius, this area breaks up atoms to its subatomic particles. This breakdown is the first step in fusing the broken-up hydrogen atoms back together to form the heavier, helium atoms. The energy released from this fusion process heats up the layers of gases above the core.

The Sun’s Rotation

Now that we understand the structure and composition of the sun, we can look at its movements. The sun doesn’t rotate in the intuitive that we’re used to thinking about rotation. We often think of rotation as a property of solid objects, such as planets. Even for planets with gaseous outer layers, they have solid cores. The sun is different in that it is a collection of plasma and hot cases, without a real solid core and this is key in understanding the sun’s rotation.

Galileo Galilei was the first man to notice that the sun rotates. He observed sunspots, spots that appear darker due to their relatively cooler temperature than their surroundings, moving across the sun’s surface.

Because the sun has layers of gas, each with their varying densities and gravitational influences, they differ in rotation speeds. The interior layers, the core, and the radiative zone, rotate similarly to solid bodies and they rotate together at the same speed and they spin faster than the outer layers.

The outer layers, however, have differential rotation, with varying rotation speeds along the sun’s latitudes. Generally, as we move from the equator towards the northern or southern pole of the sun, the number of days to make a full circle increase. At the equator, an average rotation is 25 days while it takes 35 days at the poles.

Interestingly, the sun rotates in the opposite direction as the Earth does along its axis. The sun spins from the west to the east while the Earth rotates from the East to the west.

Interesting facts about the sun…did you know?

  1. Our sun is similar to 7 billion other stars in the Milky Way Galaxy.
  2. Our sun is a yellow dwarf star, defined by its surface temperature of 5700 degrees Celsius.
  3. The name “solar system” comes from the Roman sun god, Sol.
  4. The sun is half-way to no longer being the sun as we know it. This is because the sun’s hydrogen supply is limited and the process of fusing hydrogen into helium is what gives the sun its heat, energy, and magnetism. In about 4.5 billion years, this supply will run out, causing the sun to expand and become a red giant star and later shed its outer layers, burning up the earth’s atmosphere in the process. What will be left is the sun’s core and the sun will then be a white dwarf star.
  5. It takes 8 minutes for a photon from the sun to reach the earth

Viewing the Sun through a Telescope

If you are further curious and would like to observe all these for yourself, you can do it. Thanks to specialized solar telescopes, it’s possible to view the sun without fearing to damage your eyes. Here are the top 3 most recommended solar telescopes

1.Celestron EclipSmart Solar Refracting Telescope

The Celestron EclipSmart is made to protect the eyes and give a clear viewing experience. Because the sun emits radiation, UV, and infrared light, which is harmful to the eyes, the telescope uses Solar Safe filter technology to guarantee safety. This technology is guaranteed as safe by the SAI Global Assurance Services. The clear view is thanks to the telescope’s 18x magnification capability and a fully coated lens. In its entirety, it’s easy to assemble the telescope and has great stability when viewing, thanks to its adjustable tripod.

2.Meade Instruments Coranado PST Personal Solar Telescope

This is on the higher end of the expense side and offers neat capabilities for solar viewing. It is highly portable, just 50 cm long and weighing less than a kilogram. With 400mm of focal length and 40 mm aperture, you can see the sun’s details in greater clarity. You can see sunspots, solar flares, and filaments with this telescope. Unlike the other two on this list, this one does not come with a tripod but it can be purchased separately.

3.Meade Instruments 0.5PST Coronado H-Alpha Personal Solar Telescope

This is the most expensive of the three options, however, it will also give you the best solar viewing experience of all the telescopes listed here. The Meade 0.5PST Coronado H-Alpha Personal Solar Telescope is ideal for observing the sun and allows you to see prominences and surface details. This telescope can be double-stacked for even more detail and contrast on the surface.

Additional Reading

The sun is a marvel. It’s history, creation, structure, rotation, composition and sheer size are awe-inspiring. It is the life-giving force for our planet, but also a very intimidating force. Knowing about it and the ability to study it is an amazing opportunity to get acquainted with the solar system’s mother and viewing it is possible, thanks to science’s endless pursuit to understand the universe.

Well there you have it, the answer to “Does the sun rotate?”. I certainly hope you’ve enjoyed reading this article and have found it both interesting and useful.

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