Cosmology Flashcards
1
Q
Doppler effect
A
when an observer experiences a change (e.g. in sound) due to relative motion between source and observer
2
Q
Red shift
A
Original wavelength increases when received at Earth
3
Q
Recession speed
A
Speed at which galaxies move away from each other
4
Q
Cosmic scale factor
A
Helps visualise expansion
d=RΔx
- d=physical distance after expansion
- R= scale factor
- Δx= change in x, distance between 2 points
R changes with time
