2. Harry Kroto 2004

4. 1. The masers usually switch of after ca 3 days

5. 2. So the dimension of the cloud can be estimated from the time for the light wave to pass through the cloud at velocity c.

6. 1. The masers usually switch of after ca 3 days 2. So the dimension of the cloud can be estimated from the time for the light wave to pass through the cloud at velocity c. 3. 3days ~ 1/100 th of a ly

7. 1. The masers usually switch of after ca 3 days 2. So the dimension of the cloud can be estimated from the time for the light wave to pass through the cloud at velocity c. 3. 3days ~ 1/100 th of a ly 4. This leaves all the molecules in their lower states.

8. 1. The masers usually switch of after ca 3 days 2. So the dimension of the cloud can be estimated from the time for the light wave to pass through the cloud at velocity c. 3. 3days ~ 1/100 th of a ly 4. This leaves all the molecules in their lower states. 5. It will take several days to pump up to population inversion again and switch on again

10. Harry Kroto 2004

14. Pumped into population inversion condition by source of IR radiation Harry Kroto 2004