Class Notes (1,100,000)
CA (650,000)
UTSC (30,000)
Astronomy (100)
Lecture 7

ASTA02H3 Lecture 7: Proper Motion of Stars

Course Code
Diana Valencia

This preview shows half of the first page. to view the full 3 pages of the document.
ASTA02- Lecture 7 (Jan. 29th)
- Motion of Stars
The amount of proper motion shown by a star depends on its distance
More distant stars tend to have smaller proper motions
Can usually only measure proper motions within about 1000 parsecs of the Sun
Small proper motion larger distance
Stars moving exactly towards or away from us will show NO proper motions:
- Radial Velocity
Radial velocity: how fast a star is moving directly towards or away from us
Radial velocities are measured using the Doppler Effect of the star’s spectrum
Star moving towards Earth: BLUESHIFTED
Star moving away from Earth: REDSHIFT
Star moving across our line of sight: NO SHIFT
You're Reading a Preview

Unlock to view full version