+John Hunter Not sure what you mean. But the peak in the intensity is known to be the hydrogen alpha line. Therefore, when this peak is shifted you can find out from how far it is shifted what velocity this galaxy has (since you know the difference between where the peak IS and where it SHOULD be).
So... galaxies are huge. Wouldn't the part of the galaxy that is farther away have a slightly different red shift than one closer to us? So wouldn't some of the other data points be accurate for other parts of the galaxy?
+SergeofBIBEK No. It is the speed of recession that causes the red shift. Not the actual distance; though the distance does have a relation to how fast a galaxy be be seen to be receding. The galaxy is orbiting it's own centre of mass, and so all parts are at a constant recession speed, relative to the observer. The only other effect is the actual galactic rotation, as the side that is receding is red shifted, but the side heading towards us is equally blue shifted. And so is easily accounted for and doesn't corrupt the data.
The flipbook is just the cutest thing ever.
i could hear Dr. Gray for days nonstop
These videos get me excited again about learning science and physics.
Thank you.
Love the high tech HD video recording a very low tech flip book (probably printed on a high tech printer.)
Great explanation.
+Zeedijk Mike: Lots of tools will always be useful because of their simplicity.
Some...interesting...camera work there. I can see why it was cut out.
I would like to see how a interferencefilter works.
Maybe a topic for one of your other channels?
:)
Brady, great video (as always). I don't like the fish eye filter though. It's funky.
I was wondering how they deal with redshift.
+John Hunter Not sure what you mean. But the peak in the intensity is known to be the hydrogen alpha line. Therefore, when this peak is shifted you can find out from how far it is shifted what velocity this galaxy has (since you know the difference between where the peak IS and where it SHOULD be).
Frederik Huber they answered it in this video. I was just wondering about the problem of red shift after watching the first video.
why are there comments from two weeks ago if this was just posted?
It's interesting to listen to her American accent and how it's been tempered by living abroad.
Dr Gray grew up in Canada.
.. feel like I've seen this before.
Doing your PhD in a flip book: a strong play! :D
@2:49 I was like: Alert! Alert! LEGO-mine detected! All shoes on battlestation!
I should have stayed in school... I'd be looking at great pictures of places in space right now =(
You're in the best school to have ever existed....youtube.
Why is this video unlisted?
+fpm1979 I think you are supposed to watch the main video first.
Is that a phase one back in place of the eyepiece?
nice i was wondering long time how the f u can take pics of sun :D
Mom where is my Lego?
How did this get uploaded 11 hours ago if I've already seen it? I'm confused.
Deja vu
oh, its you again.
Well done.
Hydrogen
alpha
So... galaxies are huge. Wouldn't the part of the galaxy that is farther away have a slightly different red shift than one closer to us? So wouldn't some of the other data points be accurate for other parts of the galaxy?
+SergeofBIBEK
No. It is the speed of recession that causes the red shift. Not the actual distance; though the distance does have a relation to how fast a galaxy be be seen to be receding. The galaxy is orbiting it's own centre of mass, and so all parts are at a constant recession speed, relative to the observer. The only other effect is the actual galactic rotation, as the side that is receding is red shifted, but the side heading towards us is equally blue shifted. And so is easily accounted for and doesn't corrupt the data.
rationalmartian Oh I see. I understand now. Thanks for explaining it to me! :D
Really big arms
How dare you use Mega Bloks instead of LEGO? Unsubbed.
...Who am I kidding? I could never leave you, Brady.
Wow will she take me as a PhD student?