Search found 4 matches

by gth759k
Mon May 16, 2011 7:01 am
Forum: The Bridge: Discuss an Astronomy Picture of the Day
Topic: APOD: Time Lapse Clouds and Sky Over the... (2011 May 16)
Replies: 46
Views: 22001

Re: APOD: Time Lapse Clouds and Sky Over the... (2011 May 16

At 2:31 you can see the Andromeda Galaxy in the upper left hand corner.

Image
by gth759k
Thu Nov 11, 2010 5:55 am
Forum: The Library: Information Desk and Educational Resources
Topic: Cosmology Help
Replies: 8
Views: 1148

Re: Cosmology Help

Cosmological redshift is not the same as Doppler redshift. Cosmological redshift is caused by the expansion of space as the light was in transit. That can be used to estimate the current recessional velocity, but the math is different, and the mechanism is different. How do you separate the differe...
by gth759k
Thu Nov 11, 2010 1:27 am
Forum: The Library: Information Desk and Educational Resources
Topic: Cosmology Help
Replies: 8
Views: 1148

Re: Cosmology Help

It is a common mistake to treat redshift as if it were Doppler shift. Not according to http://hyperphysics.phy-astr.gsu.edu/hbase/astro/redshf.html . I just want to shift the whole idea back into reality. For instance, you're claiming that it was the photon's journey, through the vacuum of space an...
by gth759k
Thu Nov 11, 2010 12:02 am
Forum: The Library: Information Desk and Educational Resources
Topic: Cosmology Help
Replies: 8
Views: 1148

Cosmology Help

I recently sent an email to several physics professors at CalTech and MIT with a question I have about Cosmology and only one professor (Walter Lewin) replied simply saying good luck! Its not so much of a question as it is a problem. I've talked to people about this before and the conversation quick...