- #1
racshot65
- 7
- 0
Hi,
I'm reading "The First Three Minutes" by Steven Weinberg
And am confused about this paragraph...
"Astronomers are able to measure the motion of a luminous body in a direction directly along the line of sight much more accurately than they can measure its motion at right angles to the line of sight. This technique makes use of the Doppler effect."
Now I did some research and this is what I understand currently
If the star is moving away like in this diagram you get Doppler shift
However if the star moves sideways like this there is no Doppler shift
If my understanding is correct then my question is why does the sideways motion not produce a Doppler shift its still getting further away ?
Thank You
I'm reading "The First Three Minutes" by Steven Weinberg
And am confused about this paragraph...
"Astronomers are able to measure the motion of a luminous body in a direction directly along the line of sight much more accurately than they can measure its motion at right angles to the line of sight. This technique makes use of the Doppler effect."
Now I did some research and this is what I understand currently
If the star is moving away like in this diagram you get Doppler shift
However if the star moves sideways like this there is no Doppler shift
If my understanding is correct then my question is why does the sideways motion not produce a Doppler shift its still getting further away ?
Thank You