where are we in the universe? planet? star-orbiting system? galaxy? cluster group? supercluster?...
TRANSCRIPT
![Page 1: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/1.jpg)
Where are we in the universe?Where are we in the universe?
Planet?
Star-orbiting system?
Galaxy?
Cluster Group?
Supercluster?
Universe?
![Page 2: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/2.jpg)
Our Cosmic AddressOur Cosmic Address
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968
![Page 3: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/3.jpg)
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USA
Our Cosmic AddressOur Cosmic Address
![Page 4: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/4.jpg)
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USAEarth
Our Cosmic AddressOur Cosmic Address
![Page 5: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/5.jpg)
SPaydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USAEarth Solar System
Our Cosmic AddressOur Cosmic Address
![Page 6: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/6.jpg)
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USAEarth Solar SystemMilky Way Galaxy
Our Cosmic AddressOur Cosmic Address
![Page 7: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/7.jpg)
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USAEarth Solar SystemMilky Way GalaxyLocal Group
Our Cosmic AddressOur Cosmic Address
![Page 8: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/8.jpg)
Paydirt PeteUTEP500 W. University Ave.El Paso, TX 79968USAEarth Solar SystemMilky Way GalaxyLocal GroupLocal Supercluster
Our Cosmic AddressOur Cosmic Address
![Page 9: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/9.jpg)
How do we know? How do we know? Who is responsible?Who is responsible?
![Page 10: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/10.jpg)
Early AstronomersEarly Astronomers
• 500 BC Pythagoras - thought Earth was round from moon observations
• 350 BC Aristotle - Earth at center of “universe”, planets/stars moved around Earth
• 250 BC Aristarchus - measured (relative) distance to Sun & moon using
angles; Sun very BIG; at center of “universe”
• 200 BC Eratosthenes - measured size of the Earth using angles of sun at noon at 2 places
500 250 0 250 1500 1600 1700 1800 1900 AD
PythagorasAristotle
Aristarchus Eratosthenes
![Page 11: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/11.jpg)
Ptoo bad for PtolemeyPtoo bad for Ptolemey
Claudius Ptolemey (100 - 170 A.D.)
PythagorasAristotle
Aristarchus Eratosthenes Ptolemy
Ptolemy geocentric diagram(Earth at center)
• claimed that all planets & stars orbited the Earth (wrong!)
• Earth-Centered model = Geocentric Model
• ideas last 1300 years!
500 250 0 250 1500 1600 1700 1800 1900
![Page 12: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/12.jpg)
Nicholas Copernicus (1473-1543)
Crazy (but not really) CopernicusCrazy (but not really) Copernicus
AD
PythagorasAristotle
Aristarchus Eratosthenes Ptolemy Copernicus
Copernicus heliocentric diagram(sun at center)
• proposed Earth NOT AT CENTER, but SUN IS!
• Sun-Centered model = Heliocentric Model
500 250 0 250 1500 1600 1700 1800 1900
![Page 13: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/13.jpg)
Galileo the GreatGalileo the Great
Galileo Galilei (1564 - 1642 A.D.)
AD
PythagorasAristotle
Aristarchus Eratosthenes Ptolemy Copernicus Galileo
• The Great Observer!
• 1st to observe moons orbiting Jupiter (Galilean
satellites) - proved geocentric model wrong
Galileo’s moon phases
• Venus phases
500 250 0 250 1500 1600 1700 1800 1900
![Page 14: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/14.jpg)
Keeping up with KeplerKeeping up with Kepler
Johannes Kepler (1571 - 1630 A.D.)
AD
PythagorasAristotle
Aristarchus Eratosthenes Ptolemy Copernicus Galileo
Kepler
Kepler’s Laws (3)
• Used catalogs of planets’ positions to form equations that described all planetary motion
500 250 0 250 1500 1600 1700 1800 1900
![Page 15: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/15.jpg)
Kepler’s Law # 1Kepler’s Law # 1
Planets orbit the Sun in ellipses with Sun at one focus
focus
xx
circle ellipse
x xx
![Page 16: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/16.jpg)
Kepler’s Law # 2Kepler’s Law # 2
A line joining a planet to the Sun sweeps out equal areas in equal times as the planet travels around the ellipse
C Dclose to sun
A Bfar from sun
time to go from C D = time to go from A B
travels slowesttravels fastest
![Page 17: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/17.jpg)
Kepler’s Law #2 Kepler’s Law #2
equal area, equal times
fastspeed
slowspee
d
![Page 18: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/18.jpg)
P2 ~ a3
Kepler’s Law # 3Kepler’s Law # 3
orbital period orbital radius
€
≈
P = orbital period (years), time to complete 1 orbita = orbital radius (AU, astronmomical unit)
*note: 1 AU is distance from Earth to Sun, 1.5x108 km
like lanes on a race track
![Page 19: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/19.jpg)
• Percival Lowell (1855 - 1916 A.D.) - observed canals on Mars
Modern AstronomersModern Astronomers
AD
PythagorasAristotle
Aristarchus Eratosthenes Ptolemy Copernicus Galileo
Kepler
• Carl Sagan (1934 - 1996 A.D.) - discovered hot, dense atmosphere on Venus - lead many searches for extra-terrestrial life
• Eugene & Carolyn Shoemaker - Eugene: linked Earth and moon craters to asteroid impacts - Carolyn: discovered more comets (32) than any other person
Lowell SaganShoemakers
500 250 0 250 1500 1600 1700 1800 1900
![Page 20: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/20.jpg)
We use electromagnetic waves (or light) (or radiation)
How do we know? How do we know? Who is responsible?Who is responsible?
![Page 21: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/21.jpg)
What is a wave?What is a wave?
Ocean waves Sound waves Seismic waves
Waves are traveling energy
a wave
![Page 22: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/22.jpg)
Light (electromagnetic) wavesLight (electromagnetic) waves
medium waves = visible
BIG wavelengths
small wavelengths
![Page 23: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/23.jpg)
Light (electromagnetic) wavesLight (electromagnetic) waves
infrared image
visible imagex-ray image
![Page 24: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/24.jpg)
Tools of AstronomyTools of Astronomy(telescopes)(telescopes)
• Objective - telescopes collect light (all kinds)
• Types - optical telescopes (for visible waves) - radio telescopes (for radio waves) - plus many others (x-ray, gamma, etc.)
• Determining factor: the bigger aperture (size), the better
![Page 25: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/25.jpg)
Optical TelescopesOptical TelescopesTwo types: Reflecting & Refracting
• Reflecting: uses a curved mirror to reflect & focus light
(more common)
light in
eyepiece
mirror
• Refracting: uses a lense (like eye-glasses) to focus light
eyepiece
light in
lense
![Page 26: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/26.jpg)
Main functions of optical telescopes?Main functions of optical telescopes?
• Sharpen images (resolving power)
Make things look larger?
• Make objects look brighter (light-gathering power)
yes, but….
![Page 27: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/27.jpg)
Radio TelescopesRadio Telescopes
• Radio waves collected in large dish and reflected to center antenna
light in
![Page 28: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/28.jpg)
What do radio telescopes do?What do radio telescopes do?
• Detect radio waves emitted by space objects
• Allow us to “see” different properties of space that are invisible to us - temperature, magnetic field, composition
The Moon
visible radio
Galaxy M81
visible radio
![Page 29: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/29.jpg)
Where should they go?Where should they go?
Problem: Earth’s atmosphere blurs objects in the sky
• how about a mountain top? in space?
Ideal locations:• Places away from city lights & pollution• Places high in elevation
US light pollution Mauna Kea, Hawaii
![Page 30: Where are we in the universe? Planet? Star-orbiting system? Galaxy? Cluster Group? Supercluster? Universe?](https://reader030.vdocument.in/reader030/viewer/2022032703/56649d015503460f949d4b1c/html5/thumbnails/30.jpg)
• Hubble Space Telescope
Telescopes and ObservatoriesTelescopes and Observatories(you should visit)(you should visit)
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Clark: Lowell Obs., AZ
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Clark: Lowell Obs., AZ
• Shane: Lick Obs., CA
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Clark: Lowell Obs., AZ
• Shane: Lick Obs., CA
• Kitt Peak Obs., AZ
• Hubble Space Telescope
• Keck: Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Clark: Lowell Obs., AZ
• Shane: Lick Obs., CA
• Kitt Peak Obs., AZ
• Aricebo, Puerto Rico
• Hubble Space Telescope
• Keck (et al.): Mauna Kea, Hi
• Hale: Palomar Obs., CA
• Clark: Lowell Obs., AZ
• Shane: Lick Obs., CA
• Kitt Peak Obs., AZ
• Aricebo, Puerto Rico
• Very Large Array (VLA), NM