Our Sun is too bright for us to look directly at it; doing so would permanently damage our eyes.
However, scientists have developed technology and special telescopes that allow them to view the activity on the surface of the sun.
They have discovered a lot of information about some of the Sun’s interesting features such as sun spots and the solar wind.
Sun spots are the darkened areas that show up on the Sun’s surface. The Sun has a strong magnetic activity within itself, moving the gases around.
However, sunspots are permanent and don’t move. Their appearance of movement is due to the Sun changing its size.
Eleven year solar cycle
Sun spots follow an eleven year solar cycle where they increase in activity. They come in a variety of sizes, from the smaller ones at around 10,000 miles across to the largest ones at 100,000 miles across.
The solar wind is caused by the powerful energy from the sun. This energy actually makes a kind of “wind” that travels everywhere in the Solar System.
Solar wind is made up of charged particles that flow out of the Sun in all directions in a continuous stream.
The solar wind strength is dependent upon the Sun’s surface activity. Earth has a magnetic field that protects our planet from the harmful effects of the solar wind. However, when we travel into space, our space vehicles and the astronauts themselves lose that protection.
Electric sail
Solar wind can cause damage to our space satellites and the astronauts.
Researchers have been developing an “electric sail” that uses the solar wind for propulsion in space.
Called an e-sail, the devices would harness the streams of electrons, protons, and other types of charged particles given off by the solar wind that flow from the sun.
There is a really good possibility that this type of propulsion could be in place by 2025. Use of solar wind is far safer than the dangerous and expensive sources currently used.
Facts about Sun Spots
- When we see sunspots they look very dark, although in reality they are bright. We can’t notice the difference due to how bright the sun is.
- When the solar wind hits the Earth’s atmosphere our magnetic field bounces it off of the planet in a beautiful colorful display known as the “aurora borealis” or “northern lights.”
- Oddly, sun spots rarely appear one at a time and are often in pairs.
- The solar wind has an average speed when radiating from the Sun of 400 km/second.
- The solar wind pressure creates a heliosphere that extends into the Kuiper Belt.
- When the speed of the solar wind heliosphere ends it becomes subsonic and causes a phenomenon known as a “termination shock.”
- The first sunspots were observed by a telescope in 1610 AD by Thomas Harriott, and Johannes and David Fabricus.
- The average age for a sunspot cycle is 11 years. After that, the quantity decreases.
- A Sunspot group or Active Region are the names given when two or more sunspots gather closely together.
- Sunspots are in a variety of sizes. Some are so small they can barely be seen while others are several times larger than our Earth.
- Solar wind happens when the rapidly moving particles on the sun become uncontrollable and the sun’s gravity can no longer hold onto them.
- Solar wind is often different based on where the sun is located and how fast it’s rotating.
- The speed of solar wind is higher over coronal holes due to the lower magnetic field
- Solar wind can reach speeds up to 800 km/sec or 500 miles/sec.
- Solar wind temperatures can be as high as 1 million F/800,000 C
Q&A:
- What causes the appearance of sun spot movement?
the changing size of the Sun - What protects the Earth from the power of the solar wind?
Earth’s magnetic field - What colorful phenomenon happens when the solar wind hits the Earth?
northern lights or the aurora borealis - How fast does solar wind travel?
400 km/second - What causes the solar wind?
the powerful energy of the Sun - What does the pressure of the solar wind cause?
heliosphere
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