Web Results

## Age of the universe

en.wikipedia.org/wiki/Age_of_the_universe

In physical cosmology, the age of the universe is the time elapsed since the Big Bang. The current measurement of the age of the universe is .... So a rough estimate of the age of the universe comes...

## Practice Midterm #2

www.ucolick.org/~hyesuf/teaching/ay1_2011/practice_midterm_2.pdf

than it is today while the energy density of radiation in the Universe at that time ... Based on current estimates of the value of Hubble's constant, how old is the ...

## The Age of the Universe

csep10.phys.utk.edu/astr162/lect/cosmology/age.html

Such estimates typically yield ages in the range 14-18 billion years. Hubble Time. The inverse of the Hubble constant H has the units of time because the ... H near 50 km/s/Mpc gives a larger value for the age of the Universe (around 16 ...

## The Expansion of the Universe - Cseligman.com

cseligman.com/text/galaxies/universe.htm

This value of the Hubble constant is just an estimate, as it is hard to measure ... Time since "close" to us = current distance / current speed = r / Vr = r / H r = 1 / H ... The value of 65 km/sec/Mpc implies an "age" for the Universe of 15 billion years. ..... quoting are based on the assumption that the mass of th...

## The Age of the Universe - UC Berkeley Astronomy w

w.astro.berkeley.edu/~dperley/univage/univage.html

With the currently accepted value for the Hubble constant Ho of 71 km/s/Mpc, ... of gravity using current measurements of the universe's mass density (including both ... checks on its predictions – in this case, the estimate of the universe's age t 0. ..... with adjustments made to the ages of objects within the universe based on...

## The Hubble Constant

www.cfa.harvard.edu/~dfabricant/huchra/hubble/

Hubble's initial value for the expansion rate, now called the Hubble Constant, ... The expansion age of the Universe inferred from this was only 2 Gyr, but by the ... a value of 75 km/s/Mpc, and by the early 1970's estimates from Sandage and his .... want to calcuate parameters based on the best available current numbers:.

## How Old is the Universe? - Space.com

www.space.com/24054-how-old-is-the-universe.html

Dec 20, 2013 ... Scientists determine the age of the universe using two different methods: by ... The life cycle of a star is based on its mass. ... distances to the clusters, which affects estimates of brightness and thus mass. ... Thus, finding the expansion rate of the universe — a number known as the Hubble constant — is key.

## Hubble's Law: determining the expansion rate of the Universe

www.astro.washington.edu/courses/labs/clearinghouse/labs/HubbleLaw/hubbles_law_procedure.html

... determine a value for Hubble's constant;; estimate the age of the Universe ... of the Universe has changed as the value of the Hubble constant has improved.

## The Hubble constant: How old is the universe? - The Economist

www.economist.com/node/208825

May 27, 1999 ... Knowing this number (now called the Hubble constant) enabled the cosmologists of the day to estimate the age of the universe by extrapolating backwards to the Big ... the universe thus made somewhat older—but its exact value has ... Based on the ten clusters he has bagged so far, he, too, agrees with Dr ...

## HubbleSite - NewsCenter - Hubble Space Telescope Measures ...

hubblesite.org/newscenter/archive/releases/1994/49/background/

Oct 26, 1994 ... (To calculate the Hubble Constant, astronomers also need to know how fast a galaxy ... In the past, the best ground-based observations have detected Cepheids in ... because it is needed to estimate the size and age of the universe. ... distance from earth, and Ho is the current value of the Hubble Constant.

### WMAP- Age of the Universe - Wilkinson Microwave Anisotropy Probe

map.gsfc.nasa.gov

Dec 21, 2012 ... Astronomers estimate the age of the universe in two ways: 1) by ... The Hubble constant is a measure of the current expansion rate of the ... If the astronomers who have measured the smaller values of the Hubble constant are ...

### The Age of the Universe | Astronomy 801: Planets, Stars, Galaxies ...

www.e-education.psu.edu

If we agree that Hubble's Law tells us that the universe is expanding, it also ... the universe is expanding, because we know the value of Hubble's constant (H0 ) ... You can actually calculate an estimate for the age of the Universe from Hubble's Law. ... you with how long it took for the galaxies to reach their current sep...

### The Hubble Constant - Caltech Astronomy

www.astro.caltech.edu

Apr 3, 2011 ... age of Universe, Cepheids, cosmology, distance scale, supernovae ... Our best current estimate of the Hubble constant is 73 ± 2 (random) ± ... Determining an accurate value for Ho was one of the primary motivations for building HST. .... based on entirely independent physics, give results consistent with the ...