Weekly Scientific Misconceptions: Motions of the Earth - Part 1

Seasons: What causes the changing of the seasons?

This is an incredibly common question that I get working in a Planetarium at public institution. And it is usually adults who are confused...

DISCLAIMER:

 **No person should EVER feel shamed for not knowing something**

...but that is a topic for another post... 

So what causes the changing seasons on the Earth? Well, a simple and easy answer is that the Earth is tilted. However you may already be able to see why that answer may actually lead to more confusion.

When I say that the Earth is tilted, I mean that the Earth is tilted at approximately 23.4 degrees from the plane of our solar system. For the most part, that tilt is fixed. Ever wonder why the North Star seemingly never moves? 

A common misconception is that the earth is tilted one way in the winter and flipped the other way in the summer. This is completely wrong. 

The fixed axial tilt of the Earth is what is causing the Seasons.

I can even prove it to you...

Ready? 

Go to Australia! 

What season is it there? 

Oh, the opposite? 

Okay cool! 

Because the Earth is always tilted one direction, the earth's hemispheres experience opposite seasons. 

So what is happening? 

Imagine that the Earth is a shish kabob. Yes, a shish kabob. Imagine that there is a great skewer going straight through the planet. Entering at the North Pole and exiting through the South Pole. That skewer is tilted. If you were going to extend the northern side of the skewer, it would reach all the way to Polaris (the north star) if it were long enough. Therefore this skewer is "tilted" more in one direction, towards Polaris. So as the Earth goes around the sun, sometimes the northern Hemisphere is exposed to more sunlight (summer in the northern hemisphere) while sometimes the Southern Hemisphere is exposed to more sunlight (winter in the northern hemisphere). 

OR

Hold out your hands. Hold them in front of you with your fingers pointing at the ceiling, almost as if you’re ready to clap. Now have your right hand represent the Sun, while your left will represent the Earth. Now tilt your left hand. Just slightly. While keeping your right hand stationary, move your left around the right without ever changing the angle at which your left hand is tilted. 

This is how the Earth Orbits the Sun. This is what is creating the Seasons.

This is one of the many basic motions of the Earth.

The Hubble Ultra-Deep Field.

The Hubble Ultra-Deep Field.

This image holds an incredible amount of meaning for me.

This may seem silly or cliché, maybe even a little trite, but it's true. The Hubble Ultra-Deep Field has changed my life. How you ask? Well that all starts with how it was taken.

This image was created using the most powerful telescope ever manufactured, the Hubble Space Telescope (HST). Many consider this piece of technology to be one of the most important technological achievements in human history. This image may allow you to fully understand their reasoning. On September 24th 2003 the Hubble Space Telescope began a survey of a seemingly blank spot in the sky, where there appeared to be nothing at all. This survey lasted until January 16th of the following year. After over 4 months of accumulated data this is the image that resulted. The image above is a composite image of the amount of galaxies that appear in nothing. Every single dot, smudge and smear is an individual galaxy. Each one of these dots has millions and millions of stars. Each star has the possibility of planets orbiting it. Each one with the possibility of a civilization.

This is what we see when we stare at a blank spot in the sky where nothing appears to be. This is the number of galaxies in nothing. This is a picture of 47 billion light years. It's a picture of how small we are. It is the single most important image ever taken by humanity.

However it doesn't stop there.

This image inspired me. The first time I really used it was in 2010. I was still in High School and still a little afraid of what people might say if I they knew my true passions, my true intentions. I had experienced what happens when you try to express interest in something that was not the mainstream or the conventional. I knew that no one would see me and think I was just over enthusiastic. They would all assume I was a know-it-all,  that I wasn't interesting or worthwhile to talk to because my interests were of the academic nature.

 Smart shaming. 

To be smart, especially for a small attractive female, unfortunately comes with its own stigma in our "modern day society".

Beyond this. When I stumbled across this image, I was again, inspired. So I took a leap of faith. I did what every 17 year old girl with nothing to lose would do. I posted it on my Facebook.

The response was lack luster at best. But that wasn't the point. I didn't care that I didn't get 30 likes and 10 shares on this post (instead I got 1 like and 0 shares...). That wasn't the point. The point was that posting this image and sharing my interests publicly, and not just to close friends, felt liberating. I finally gave zero shits. This allowed me to build more confidence then I had ever seen in myself before. It allowed me to excel in the area that I am best at. Educating others. This image inspired me to inspire.

Again, it doesn't stop there.

More recently in the summer of 2014, I was given an incredible opportunity. At this point I had graduated High School, was working on my AS-Transfer Degree at a local community college, and working Part-time at the Pacific Science Center in Seattle as a Performance Educator. I was leading live immersive planetarium shows to the general public daily. I was loving my job, but feeling as if my wheels were spinning and I wasn't gaining any traction. It was then that I got unbelievable news. My supervisor was resigning.

Now no, I know what you’re thinking. I wasn't going to apply for her job. I would have never gotten it! I was still working on a degree and at this point had absolutely no formal education in either astronomy or teaching. So that wasn't what the opportunity was. Her leaving is what allowed the actual opportunity to present itself. Someone needed to develop the next NASA funded show we presented in the Planetarium, and they wanted me to be a co-developer. 20 years old, working towards a career in informal education, no college degree, and already developing content for one of the better respected planetariums in the country?! I think yes. So I did it. Alongside my co-author and developer, we created a show that we are both really proud of, a show that will continue to be presented for at least once a day for the general public through the next fiscal year.

So where does the Hubble Ultra-Deep Field fit into all of this.

Well as I said. This image inspired me to inspire others. So I put it in the show. Our show, "The Outer Limits: Pluto and beyond" is a forty minute, interactive exploration of our solar systems and the boundaries of space that lay beyond it.

It was, in my opinion, the perfect tribute to an epic image. 
An image that I hope continues to inspire others to inspire.

Specifically every day, at the Willard Smith Planetarium around 2:30 pm.

:)