astronomy early insights and a context for humanity

Astronomy

Early insights and

A context for Humanity

Do you know what this is?

What is the basis for each of the following units of time?

• Day

• Week

• Month

• Seasons

• Year

How about these?

• Hour

• Minute

• Second

Where do we get the names for our days of the week?

• Sunday

• Monday

• Tuesday

• Wednesday

• Thursday

• Friday

• Saturday

Where do we get the names for our days of the week?

• Sunday – Sun’s day• Monday – Moon’s day• Tuesday – Tiw’s day (Norse god)• Wednesday – Wodin’s day (King of Norse gods)• Thursday – Thor’s day (more Norse mythology)• Friday – Freya’s day (still another!)• Saturday – Saturn’s day

The connections get clearer

Day Germanic Romance Object

Sunday Sol Sun

Monday Lunes Moon

Tuesday Tiw Martes Mars

Wednesday Wodin Miercoles Mercury

Thursday Thor Jueves Jupiter

Friday Freya Viernes Venus

Saturday Sabado Saturn

Why was astronomy so important to ancient civilizations (e.g.,

Babylonian, Egyptian, Greek, Norse, etc.)

• A means of keeping time (calendar)

• Recurring, predictable changes in the heavens

• When to plant, when to harvest, when the Nile would flood, when to collect taxes, etc.

Were there other applications?

• Order in the heavens

• Might this order extend to peoples’ lives too?

• So… maybe people’s futures can be predicted

• Hence, the pseudoscience of Astrology

What’s your sign?

• Astrology is based on ancient Babylonian religion

• It relies on a series of assumptions that have been debunked by science

• So, what are these assumptions?

Assumptions inherent in astrology

• Earth is the center of the universe

• Sun, moon, planets and stars, including constellations revolve around Earth

• Constellations are “real”, i.e., they define real shapes in two dimensions

Assumptions inherent in astrology

• Calendars haven’t changed through time

• Unknown forces from stars that are billions of miles away affect people more than DNA!

Earth in context

Earth

• One of nine planets orbiting a central Star – the SUN

• Sun is one of about 100 billion stars in the Milky Way Galaxy

• Milky Way is one of 28 galaxies in a cluster called The Local Group

• The Local Group is one of trillions of galactic clusters that make up the Universe

Andromeda Galaxy

Spiral Galaxy –like the Milky Way

Just how big is the Universe?

• Consider the following:

• Each galaxy has 50-100 billion stars

• Classroom demonstration – 1500 galaxies

• Example: look in the cup of the Big Dipper

• This area of space holds about 1 million galaxies!!

Hubble images a part of the Universe