History of Astronomy Part 1: The Celestial Sphere and Early Observations

Now that we've learned about how the universe began, as well as the development of the Milky Way galaxy, the solar system, and the Earth, it's time to learn about the human beings that came to inhabit the Earth. Eventually, they began to look at the sky and wonder about what they were seeing, which initiated a journey of discovery that has brought us to the knowledge we have today, and have been discussing throughout this playlist! How did our ancestors figure out all this stuff? Let's go through the major breakthroughs over the next few tutorials!

Check out "Is This Wi-Fi Organic?", my book on disarming pseudoscience!

[ForgivenHim]

This is exactly what I was looking for! Not too dumbed down, but not too complex. Thank you!

[babsu]

Fantastic graphics! I've been looking for videos for my classroom, and not only are you terrific at explaining things, but you go at a nice pace. Great job!

[aa-jtyt]

i love the subtle "see flat earthers ur fucking wrong" every time he explains something

[schifoso]

This episode was very well done. Looking forward to the next in the series.

[Artlutherie]

I rarely leave comments - but I gotta say you did a great job with this series.

[anthroposlogica]

This guy is great. Never had i imagined I'd understand basic astronomy like this.

[zharth.]

I'm happy to see your subscriber count continuously increasing, you really deserve it. I've learned a ton from your videos, and I especially appreciate the self-awareness of how you articulate specific concepts. You have a very clear understanding of what it means to not already understand something, and you tap into that very well. The fact that you include opposing arguments while explaining things is just perfect.

Thanks!

[cgaccount]

I have to admit I thought moon phases were related to shadows but i never quite knew why. Thanks for the correction! I'm happy to say I've never thought aliens visited the earth and piled up rocks.

[justgonnastay]

The word "planet" comes from the Greek "planetes, " which means "wanderer." This is because they moved independently of the stars, so they wandered about the night sky. I find this fascinating.

[michaelpisciarino]

1:15 Ancestors
- Constellations
- Sun, Moon, Planets

2:52 The Geocentric Model
3:47 The Day "Sunrise, Sunset"
The Month "Moon's Cycle"
The 4 Seasons, The (Earth) Year = 1 (Earth) Revolution around the Sun

5:00 The North Star
5:45 Constellations mark passing of time. They appear and disappear in cycles

6:54 How do we have seasons?
The (23.5 degree) Tilt in Earth's Rotation and The Sun

8:23 Equinoxes and Solstices
8:58 Stonehenge

9:40 The Moon ((1) New Moon, Waxing Crescent, , Waxing Half, Waxing Gibbous, Full, waning Gibbous, Waning Half, Waning Crescent, New Moon)

[EricBurns]

As a brand new high school astronomy teacher I was going through the curriculum list of videos for our history unit and was happy to find this on it. 138 high schoolers have been introduced to your material.

[Master_Blackthorne]

Professors are human beings? When did this happen? 😁😁😁

[PunmasterSTP]

Celestial sphere? More like “I’m really glad Professor Dave is here!”

[RooseveltVilna-bjso]

Hi prof Dave. Can u make a serie on the Anunakis n the Sumerians?

[emmaaguila]

Thank you Dave! This was something I never had the imagination to understand. Until now.

[shivamchouhan]

Thank you for such fantastic explanation

[williamliamsmith]

Very nicely explained BUT there is a major issue at 5:30. Non moving star at celestial North Pole was not seen by ancient ancestors for most of the time - except for some short time between 3800 BCE and 2200 BCE when Thuban was close enough to be perceived as non moving and 1200 CE to now when the Polestar was close enough to be non moving. It will be closet to celestial North Pole around 2100 CE and slowly drift away.

[mechamanmike]

Three classes now. three separate classes have had me watch this guys vids.

[BParker]

Great video, though I don't know if I'd say the lunar phases have _nothing_ to do with shadows; just not the shadow of another object (which is what I think you meant). It's undeniable that the dark portion of the moon is dark because it's shaded from the sun, but it is in fact the *moon itself* which provides that shade.

[fallendown]

With just enough observation we can end our ignorance and this is why science and it's methods are the thing enlightens humans the most. Not saying "it is because of the invisable gods" and actually look for a patern