SOAR Fall 2004SOAR Fall 2004

Earth’s place in the cosmos

Earth’s place in the cosmos

Population of the CosmosPopulation of the Cosmos~100 Billion Galaxies =

1011 Galaxies~ 100 Billion Stars in

each galaxy = (1011 stars)

(1011 Galaxies)= 1022 stars

~ 10 planets around each star =

1023 planets … potentially lots of

company, but it’s very far away!

~100 Billion Galaxies = 1011 Galaxies

~ 100 Billion Stars in each galaxy = (1011 stars)

(1011 Galaxies)= 1022 stars

~ 10 planets around each star =

1023 planets … potentially lots of

company, but it’s very far away!

Earth-Moon DistancerEM = 250,000 miles

Earth-Sun Distance93,000,000 mi = 1 AU

(372 rEM = 1 AU)

Sun- Centauri Dist.4 ly = 4(63,200 AU)

(1 ly = 6x1012 mi)

Milky Way DiameterRMW = 100,000 ly

MW-Andromeda Dist.Rand = 2,000,000 ly

Farthest Galaxy Rfar = 11 Billion ly

Earth-Moon DistancerEM = 250,000 miles

Earth-Sun Distance93,000,000 mi = 1 AU

(372 rEM = 1 AU)

Sun- Centauri Dist.4 ly = 4(63,200 AU)

(1 ly = 6x1012 mi)

Milky Way DiameterRMW = 100,000 ly

MW-Andromeda Dist.Rand = 2,000,000 ly

Farthest Galaxy Rfar = 11 Billion ly

Scale of the CosmosScale of the Cosmos

= 264,000,000,000,000,000,000 rEM

= 264,000,000,000,000,000,000 rEM

Motion of EarthMotion of EarthRotation on axis

vEquator ~ 1000 mph, vCanton ~ 700 mph

Orbit about SolvEarth ~ 70,000 mph

Orbit about center of Milky WayvSun ~ 560,000 mph

Milky Way in Local GroupvMW ~ 280,000 mph

Local Group falling toward Virgo ClustervLG ~ 1,750,000 mph

Rotation on axisvEquator ~ 1000 mph, vCanton ~ 700 mph

Orbit about SolvEarth ~ 70,000 mph

Orbit about center of Milky WayvSun ~ 560,000 mph

Milky Way in Local GroupvMW ~ 280,000 mph

Local Group falling toward Virgo ClustervLG ~ 1,750,000 mph

The Milky Way GalaxyThe Milky Way Galaxy ~ 300 Billion Stars, some with planets

~ 300 Billion Stars, some with planets

The Milky Way GalaxyThe Milky Way Galaxy

Sun ~ 30,000 ly from centerGalactic Year ~225,000,000 yr (Sol is ~22)

Sun ~ 30,000 ly from centerGalactic Year ~225,000,000 yr (Sol is ~22)

M87, a galaxy much like the Milky Way

http://www.eso.org/outreach/press-rel/pr-1999/pr-18-99.html

Solar SystemSolar System Sun & Planets formed from

interstellar clouds collapsing under gravity

Sun & Planets formed from interstellar clouds collapsing under gravity

Solar SystemSolar

System

Inner Worlds: Mercury, Venus, Earth, Mars

Inner Worlds: Mercury, Venus, Earth, Mars

Positions at 17:00 UT, 1/23/04

1 AU = 150,000,000 km= 93,000,000 mi

Solar SystemSolar

System

Outer Worlds: Jupiter, Saturn, Uranus,

Neptune, Pluto

Outer Worlds: Jupiter, Saturn, Uranus,

Neptune, Pluto

Positions at 17:00 UT, 1/23/04

SS width ~ 12,000,000,000 km~ 7,500,000,000 mi