1. Expansion of the universe

2. Edwin Hubble ( )
Observed ‘nebulae’ and from measurements of distance, using Cepheid Variable stars, he concluded that they were so distant that they could not be located within our own galaxy. In fact they were not clouds of dust and gas, but entire, distant galaxies.

6. What is the Hubble constant H0?
It is a measure of the expansion of the universe
It is a measure of the expansion at the present time
The recession velocity v=H0D, where D is the distance to a particular galaxy (or light source). This is the Hubble Equation
Most up to date measurements confirm that H0 is around
70kms-1Mpc-1

7. What are the SI units of the Hubble constant?

8. What is the value of the H0 in s-1?

9. What is the significance of 1/H0?
It is the approximate age of the universe in seconds.
Convert this to years.