Train your Brain – See the shape of the solar system

Physical Astronomy by Daniel Cummings.

Train your Brain - See the solar system disk

See the solar system from Earth

Most people, when they look up at the night sky can easily see stars and identify some familiar groups of stars (asterisms and constellations). Some people can even find and name some planets – Venus, Jupiter, and Mars are all bright and easy to see.

But, there are many invisible wonders in the sky – and some of them can be seen without a telescope. In fact they are so big that a telescope is not the right tool to use; we have to use something even more powerful… imagination!

Using visualization and imagination, I am going to show you how to find and “see” a very large structure in our sky: the solar system disk itself.

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Groundhog Day Shadow Tracker

Physical Astronomy Tool by Daniel Cummings

Groundhog Day Shadow Tracker Lesson Plan
It’s Groundhog Day!

What better way to celebrate Groundhog Day than to Build your own Groundhog Day Shadow Tracker


Sun Tracker Window Gel Cling and Stickers to track the Sun

UPDATE: We now sell an astronomy gift called the Sun Tracker that teaches you the same Basic Astronomy Lesson that the Ground Hog does! You can learn all about the apparent movements of the Sun and the analemma.

It’s called the Sun Tracker and you can purchase one right from this website.


Let’s do some Physical Astronomy. The experience will help you to understand the movement of the earth and sun through the seasons. You will build a scientific instrument that is also a fun garden decoration and you will be able to track the Groundhog’s Shadow all Spring!

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What Looks Like Sunset

English: The sunset seen from Shwesandaw Pagoda in Bagan, Myanmar. Date 9 December 2014, 17:23:27 Source Own work Author Jacklee Camera location 21° 09′ 49.23″ N, 94° 51′ 58.11″ E Heading=76.098113207547° Is what looks like sunset really the sun – “setting”?

What is that thing that happens every day that makes it look like sunset?

Can you change your mind easily? Are you flexible enough to understand that the same set of observations and facts can lead two different people to two different conclusions?

For a long time, everyone on the Earth thought the Sun was moving and the Earth was staying still. This is just what it looks like and anyone who dared to suggest a different view might easily be considered odd, or worse, dangerous. Having the benefit of hundreds of years of scientific evidence and wisdom to back up my observations, I now have the luxury of believing that it is the Earth that is moving and that the Sun is the one standing still.

It is fun to imagine being carried through space on the surface of a giant ball. Definitely better than staying still while the sun careens through the sky each day. With this image in my mind, I feel the Earth is carrying me away from the view of the Sun.

Sunset should be called “away sun” and not “sun set” because it is me moving, not the sun. It is me being carried away into the shadows forming behind the bulge of the Earth, not the Sun setting. I am riding the Earth with its great round bulk between me and the Sun.

It’s NOT a sunset but me… rushing backwards… at 1000 mph as the bulge of the earth grows in between.

I propose “awaysun” as the new name for sunset and “towardsun” as the name for sunrise. These new names help solidify the idea that we are the ones moving.

What do you think?

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