Western Washington University   College of Sciences and Technology   Physics/Astronomy Dept.   Bellingham, WA USA
 
ASTRO 101

Analemma
Asteroids
Aurora
Big Bang
Black Holes
Bode Titius
Brightest Stars
Comets
Constellations
Coordinates
Cosmology
Cruithne
Dark Matter
Eclipses
Galaxies
Historical
HR Diagram
Hubble's Law
Intelligent Life
Kepler's Laws
Leap Year
Light Waves
Lunar Libration
Messier Objects
Meteors
Milky Way
Moon
Moon Phases
Planets
Precession
Rainbows
Redshift
Seasons
Stellar Evolution
Stardust
Sun & Fusion
Telescopes
Tides
Time of Day
Twilight
Zodiac
 
Hubble's Constant
Hubbles Law   Hubble's Constant   Raisin Pudding   Activity Lab   Galactic Recession   Galactic Redshifts   Exam

Pichon et al., MNRAS, 2001, 326, 597. click to enlarge
Millions of galaxies mapped in their relative positions to
each other show the large-scale structure of the Universe.









In 1929 Edwin Hubble estimated the value of the expansion factor of the Universe, now called Hubble's Constant, to be about 500 km/sec/Mpc. Today the precise value remains uncertain but is generally believed to be in the range of 45 to 90 km/sec/Mpc.

The value is important to cosmologists because it can be used to estimate the age of the Universe.






Results (February 2003) from the Wilkinson Microwave Anisotropy Probe (WMAP) indicate that the Universe is 13.7 billion years old   (Ho = 73 km/sec/Mpc).