Why is the Sun's Corona much Hotter than its Photosphere? - Science Journal Entry Two

The heat source for stars is located at their cores, in the very centre of them. The Sun’s Corona is further from this heat source that the suns photosphere yet the suns corona is still 200 times hotter than its photosphere. On Earth, the further in you go towards the earth’s core, the warmer it gets, but this is not the case on some stars. Scientists have been studying why the corona of some stars are much hotter than their photospheres. The believed cause for this is megnetohydrodynamic (MHD) waves that disperse energy created from below the stars surface to the outer layers of their atmospheres. A team of English Scientists has examined the MHD waves emitted by the sun and by their calculations, they concur that it is possible that the MHD waves cause the heating of the suns corona. Their data shows that the MHD waves transport energy from below the solar surface, through the chromosphere and into the corona, causing it to heat up to 200 times more than the stars photosphere.  

I chose this article simply because I stumbled upon it on a science website, and it seemed interesting. Since I was a little kid, I was always amazed at what goes on in outer space, what happens beyond planet earth. Before I saw this article, I had no idea that the temperature of the Sun’s corona is much warmer than its photosphere. I though by choosing this article, I could question myself more about how the sun works, and expand my knowledge on the topic.

I think that this topic is scientifically correct. After reading the article over a couple of times, the extra heat being diverted to the sun’s corona is a plausible solution to why the sun’s photosphere is colder than its corona. The atmosphere on our planet helps keep the heat on the surface of our planet, and not have it all escape into outer space. This is like the opposite of the reaction that happens on the sun. On earth, all of the heat is goes as far down as possible. On the sun, the MHD is pulled through energy throughout the sun, hearing up the corona much more than the photosphere is heated.

This explanation of why the suns corona is much warmer than its photosphere is still just a theory. Studies about this topic are currently being undertaken at Northumbria University. Even though this is still just a theory, and there is no way to currently tell if this is actually what is causing the sun’s corona to heat up so much, it seems as if it is the only plausible solution. I may not be a scientist by any means, but there is no other explanation that I can think of that can possible heat up the sun’s corona much more than its photosphere.

The one question I have after reading this article is the following: How do you measure the temperature of the sun? The sun is well in the millions of degrees, and I have no idea how humans measure the temperature of the sun. Unfortunately, we cannot send a random person in a large spacecraft out to the sun, hold up a thermometer and check the temperature of the sun. I would really like to know how this process works, and how some people can determine the variables of items that we will never be able to reach. 

Original Article from Science Daily

You Live in the Past/The Flash Lag Effect - Science Journal Entry One

This video explained the theory of how we human beings live in the past. Nerve impulses can only send information to our brain at a top speed of 250 miles per hour. This means that our brain does not receive data instantaneously, but rather after a short delay. Testing was done by rotating a circle with a flashing centre around on a screen in a circle, and telling participants to look in the centre. When the participants described what they saw, the said that they saw the flashing light slightly outside of the circle, on not inside it. This is known as the flash lag effect. After testing was completed, it was found that humans can only tell an event happened about 80 milliseconds after the fact. For example, let’s say you just picked up a pencil. You think that you just picked up the pencil but you actually picked up the pencil 80 milliseconds ago. Since there is a delay for every action that takes place, you start to get used to it, and eventually, you experience no lag at all. Tests have been conducted that simulate this theory. If you get a test subject to press a button that turns on a light 80 milliseconds after the button was pressed, the participant will eventually get used to the delay and forget it is even there. When the delay was shortened to 40 milliseconds, the subjects claims that they did not touch the button, and the light turned on.

  I chose this topic because I found it interesting that nothing happens in so called “real time.” Everything that happens has actually happened slightly in the past. I found this quite interesting because whenever I do something, I think back to this video, and think about what I did actually already happened, even though I thought that it just happened.

 I believe that this is scientifically correct. After multiple tests, scientists were able to recreate the results of how our brain receives signals in the past. If a user controls a light with a button, and the light comes on less than 80 milliseconds after the button was pressed, the user says that they did not touch the button and the light came on. It also makes sense because the brain cannot receive signals immediately. There has to be a pause before our brain can fully comprehend what is going on.

   
Proof to this theory can be shown by the flash lag effect. In the tests, test subjects looked at a flashing dot in the middle of a rotating circle. The users said that the flash was occurring outside of the circle, even though it was in the centre of the circle. This theory can also be proven because the top speed of neuron impulses is 250 miles per hour, and many impulses travel slower than this. That means that our brain does not receive signals from our surroundings instantaneously, but rather, after a short delay.

This is another way of demonstrating the flash lag effect. The bar on the bottom appears only when the top bar is aligned with it, although this is probably not what you see. Most likely, you see the top bar slightly past the bottom bar when the bottom bar appears. This is caused by the flash lag effect.