A Tour of the Milky Way
Manuel Pichardo Marcano
he/him/his
Department of Physics and Astronomy
One-Third of Humanity Can't See the Milky Way
The legend
\Gamma \alpha\lambda\alpha\xi \acute{\iota}\alpha\varsigma \text{ from the greek } \gamma\acute{\alpha}\lambda\alpha \text{ (milk)}
Acáyouman:
Celestial Caiman
"Discovery" of the Milky Way
-
Galileo Galilei (1610):
- “The Milky Way is nothing else but a mass of innumerable stars planted together in clusters.”
- William Herschel (1784):
Center of the Galaxy
“It is believed that the great mass of the stars ... are arranged in the form of a lens-or bun-shaped system ... considerably flattened towards one plane ... the Sun occupies a fairly central position.”
—Arthur Eddington, 1914
"It is worthy of notice...that the brighter variables have longer periods.
—Henrietta Swan Leavitt (1908)
A tool to measure distances
"It is worthy of notice...that the brighter variables have longer periods.
—Henrietta Swan Leavitt (1908)
A tool to measure distances
Star Clusters
Globular Clusters
Variables in GCs
The Galactocentric Revolution
The center of the sidereal system is distant from the Earth.
— Harlow Shapley (1918)
Do the same with other regions
Current Model
How big is the Milky Way Galaxy?
The Milky Way (to scale)
How far is 100,000 light years?
- 1 inch represents 5.5 light hours (Sun to Pluto)
- 1 mile represents 40 light years
2,500 miles
represents
100,000 light years
North America
And how thick is our Galaxy?
How thick is 1,000 light years?
If 2,500 miles represents 100,000 light years
25 miles represents 1,000 light years
\sim 30 \text{ miles Lubbock to Levelland}
200 Billion Stars
Bird seeds 4 feet deep
The Tour
Dark Matter Halo
No dark matter Dark matter
Globular Clusters
~150 known in the Milky Way
A Zoo of Exotic Objects
Gas around BH
Thank you
Extra slides
Subtitle
A tour of the Milky Way
By mmarcano22
