Upside Down and Opposite Seasons

It is well established that the Seasons in the Northern Hemisphere and the Southern Hemisphere are opposite.  We know that if we fly to Australia, from Fort Worth, Texas in the dead of winter, we will arrive in Australia to some very high and hot temperatures.  I imagine this surprised quite a few people in the early days...hop in the plane all dressed with winter clothes and land in another country and it's full on summer!

The tilt of the Earth is real!  It doesn't matter what time of the year it is, the Northern Hemisphere season is opposite the Southern Hemisphere season.  The science for this is a very interesting story.  The reason we are tilted may be due to the fact that in the early Solar System there was a lot of stuff revolving around the new Sun.

These random objects of rock, dust and elements came together by the force of gravity.  Our Earth was a very hot sphere and was knocked around a little bit by pieces of rock that were still floating around. 

We learned that a large object hit the Earth and possibly this is how the Earth was tilted and our moon was formed.  As the planets grew larger from "sucking" in pieces of rocks, dust and elements the gravitational pull increased for each of them.  It makes sense that as the planets orbited around the Sun and ran into the space "stuff" in their path, they could all have encountered a collision and been knocked sideways from a straight up and down rotating axis. 

Did you know that WAY, WAY back in the old days, when the old Earth was a new Earth it rotated faster?  It has been calculated that the Earth completed one "spin" in 6 to 10 hours!  If we think time goes quickly now?  I'm so glad for our 24 hours...trying to fit in all my work in 6 to 10 hours would be very complicated and HARD!  

Imagine what would happen if our world was knocked back to 0 degrees?  Life would be so different!  Getting on a plane in Texas and landing in Australia would mean temperatures and seasons would all be the same.  For me, it would feel kind of like everyone having to wear the same uniforms to school everyday.  The Earth would be boring...all the sameness would be...

blah....

Reason for the Season's #3: Revolution of the Earth

Finally, one of the last reason's for the Season's is...the REVOLUTION of the Earth around the Sun.  If you have been keeping up, the number 1 reason for the Season's is the TILT of the Earth.  The number 2 reason for the Season's is the ANGLE OF THE SUN's RAYS.  Are you ready to tackle the Revolution??

UGH!  Not that revolution!  The REVOLUTION of the Earth around the Sun!  Remember your definition of REVOLUTION (in space), is one object traveling around another object!!

It takes the Earth 365 days to travel around the Sun.  I've never been to Europe, but I've been around the Sun quite a few times!  As the Earth moves along it's path the two hemisphere's, Northern and Southern shift positions.  This is due to the tilt of the Earth mind you...

The axis is imaginary, but it really helps us to see how the Earth leans away from the Sun and leans toward the Sun as it goes around the Sun.  When the Earth is leaning toward the Sun, temperatures increase, yeah it gets hot!  When the Earth leans away from the Sun, temperatures cool and it gets down right cold in some places.  This is true for the opposite hemisphere...all that I said, but opposite from what I said...

Alright, I'll back up.  When the Northern Hemisphere is tilted toward the Sun, it is hot and summery.  On the other side of the world, in the Southern Hemisphere the temperatures are cold...

If the Earth were to tilt a little bit more toward the Sun and a little bit more away from the Sun, would this affect our climate?  OF COURSE! 

Climate changes over a long period of time, so there won't be any sudden changes in tilt unless we are hit by something large, like an asteroid...I think at that time we would be more worried about other things if that happened...like, our lives? 

Just a simulation, but looks pretty awesome! 

Reason for the Season #2 Angle of the Sun's Rays

The main reason for the Seasons is the TILT of the Earth's axis.  But there are other factors that come into play as well...the second reason is THE ANGLE OF THE SUN'S RAYS. 

Our star, the Sun, is a YUGE ball of energy!

When the Sun shines on us, tiny photons, or packages of energy are thrown at the Earth and hit it with amazing force.  We have felt this in July when we are waiting for 4th of July parade to start and our skin is just prickling with heat and we want to hide under a tree or an umbrella.

The Sun produces 360 billion billion (nope, I didn't stutter) megawatts of power per day. Using math physicists have calculated that this equals 4 million tons of hydrogen per second burned by our star to heat the Solar System. 

That's right!  That's a lot of energy that hits the Earth.  Even though we are the size of a pea compared to the Sun, our distance keeps us from burning up into a black cinder.  When it comes to the seasons...our tilt causes those photons to hit directly or indirectly.  An indirect hit means the energy is dispersed, or less hot.  I'm not kidding! 

We can measure the angle of sunlight by using time.  Many young scientists have charted the exact time the Sun sets over a period of months.  During the summer the pattern shows over and over that in the northern hemisphere the daylight hours are longer, the temperatures are warmer than in the Southern Hemisphere where the daylight hours are shorter and the temperature is colder.  This is all attributed to the TILT and the ANGLE OF THE SUN'S RAYS.  

Reason for the Season #1 Tilt of Earth's Axis

The NUMBER ONE reason for the Season's is the TILT of the Earth's axis.  Did you know that our Earth is tilted 23.4 degrees compared to its orbital plane, or compared to the path the Earth takes around the Sun?

This tilt affects the Seasons on Earth. Some parts of the Earth are tilted toward the Sun and other parts are not tilted toward the Sun and this makes our temperatures and weather patterns different in different places and different times!

Okay, I'll say it simply:  No tilt equals one season!  How would we know and why do we care?  Would we be the same Earth with one season?

Scientists believe that with only one season the Earth would be surrounded by weather bands.  Very warm and moist around the middle of the Earth and progressively colder and drier as you traveled North or South.  Life probably wouldn't survive at the poles because it would be very cold, and tons of life would be living near the equator.  Would all 7 billion of us humans fit around the equator?  Let's look:

Look closely at the band around the equator from 0 degrees to 23.5 degrees.  It's mostly water!! Look where all the land masses are, above 23.5 degrees.  Whoa!  It would be really crowded in Africa and South America...

We would have to live together, and hopefully have enough room to grow a garden so we could have some fresh fruit and veggies?  The more I think about it, the more I appreciate our tilt!

With the Earth tilted different parts of the Earth receive direct and indirect sunlight.  Wheat grows where it is cooler, fruit grows where it is warmer.  Everything kind of balances out.  So, I wonder what made the Earth tilt?

Remember when we watched the theory about the formation of the moon...

It's possible this is how our Earth got tilted.  But we weren't there at the time, so maybe there is another reason the Earth was tilted...

Being tilted is not a bad thing.  The Earth is tilted, everyone loves the Leaning Tower of Pisa, and it's nice to lean on something or someone once in awhile...

It's cool to be tilted!!  (And warm in other places because light hits directly and indirectly...)

Polaris. The North Star

Hidden in the Little Dipper is a very special star...Polaris, the Pole star.  It isn't just a Pole star, it is OUR Pole star!

To find it we just use the BIG DIPPER and it is one of the brightest stars in the handle of the LITTLE DIPPER.  Many explorers have used the North Star to guide their way in their travels.  Boy and girl Scouts use the North star when camping or hiking at night as a precaution to help them not get lost. 

This North star just happens to line up with our imaginary axis of rotation that points to the North. 

Photographers love to make star trails using the North Star because it shows us the point at which we rotate.  Polaris stays in the same place all night long as the other stars rotate across the sky. 

Watch this satisfying video of star trails made in the Northern Hemisphere compared to the Southern Hemisphere.  Can you tell the difference?  Can you see the North star, our Pole star?  

Hint:  The Southern Hemisphere does NOT have a Pole star.... 

Seasons Misconceptions

The days get shorter, the nights get colder, the leaves on the trees start to turn red, yellow, and orange.  Winter is coming, why do these changes happen where we live every year?

Some people say the Earth is moving around the Sun in its regular orbit and moving farther away from the Sun.  That makes sense but the idea is:

Other people might say seasons happen all over the Earth at the same time.  Again, good idea but its:

Or people believe, it's winter when it's cold, and summer when it's hot: 

Why do we believe such things?  Well, it might be we don't haven't understand the tilt of the Earth.  Is it all about the tilt?  Yup!  It really is all about the tilt.

Let's start at the beginning...The Earth revolves around the Sun in an orbit, or path.  At one time astronomers believed the orbit was perfectly circular.  In 1609, an astronomer named Kepler, using math and observations calculated that the Earth's orbit was in an oval, or slightly elliptical.

If we include the tilt of the Earth and this slightly elliptical orbit, this movement results in four seasons; summer, autumn, winter, and spring.  But, not all over the Earth...

Because the Earth is tilted one hemisphere is tilted toward the Sun while the other hemisphere is not.  It's true that when the Northern Hemisphere is enjoying winter, the Southern Hemisphere is enjoying summer.

We need to remember that the world is an very LARGE planet compared to us little humans.  What we experience in our neighborhood could be completely different in the state next to us, or even across the entire world.  I think that's why people love to travel...it helps us understand our world and our neighborhood a little bit better. 

Trash on the Moon

Okay, I had to bring this up...if we have colonies on the Moon, what are we going to do with all the trash they make?  I know the International Space Station puts it in bags and ejects it into space.  When the space trash bag loses speed it falls into the atmosphere and burns cleanly away before anyone even knows about it.  But Moon trash?  This appears to me to be a problem that needs to be considered. 

United States Moon rover...

Soviet Union Moon rover...

China's Moon rover...

Can you understand my concern?  In a hundred years will we look at the moon through our telescope and see spots of trash all over the moon? It's starting, right?  

There is a lot of bizarre stuff being left on the moon:

1. China left an actual biosphere that contained plants like cotton and potatoes.  They were able to plant the seeds and the plants actually grew until the Moon's shadow covered the biosphere and then they froze to death.  They left the biosphere on the moon with dead plant starts in it...

2. Bags of poop. No explanation needed...

3. Photographs of families...

4. Batteries

5. Remote controls

6. Shoes

7. Cameras

8. Cables

9. Handles

And I could go on and on.  From my research NASA wants to go to the moon and bring this stuff back because it has become a part of history.  So these are artifacts from the past that will probably be put in a museum somewhere, except for the poop, I hope!

I have an idea!  Why don't we figure out how to take care of the Moon trash problem!  Couldn't we figure this out?  Sixth graders are very good at figuring things out.  I say let's do this!  Come on, what do you say?  

You never know, maybe we could all get rich, very rich....

or not...