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Fraser
2007-Mar-05, 05:00 PM
This week we continue the story of galaxy formation, learning how groups of galaxies come together to form the biggest structures around - galaxy superclusters. And when you look at the Universe at this scale, environment is everything.

Read the full blog entry (http://www.astronomycast.com/extragalactic/episode-26-the-largest-structures-in-the-universe/)

Blob
2007-Mar-05, 06:27 PM
Hum,
another interesting episode,
but this is getting close to the maximum size that people can comfortably download on a 56kb modem in a 2 hour period.

Galaxy
2007-Mar-05, 07:37 PM
Hum,
another interesting episode,
but this is getting close to the maximum size that people can comfortably download on a 56kb modem in a 2 hour period.

Blob,

If you want to download the mp3 or the 16kb version of any show, you can always visit our archive (http://astronomycast.com/archive/) for a listing of all our shows and links to download in the format of your choice.

Additionally, there are links at the top of each episode's page to allow you to download the mp3 if you'd prefer it to then m4a. The mp3 will always be a much smaller file.

Hope that helps.

-Rebecca
Astronomy Cast Student Worker

Blob
2007-Mar-05, 09:46 PM
Hum,
tnx, i didn't realise there was an economy class (http://media.libsyn.com/media/astronomycast/AstroCast-070305.mp3) Internet connection link available (14mb, mp3).

Fraser
2007-Mar-05, 11:19 PM
We've thought of everything. :-)

llarry
2007-Mar-06, 04:43 AM
Fraser Pamela and Rebecca,

Another great show, thanks for all your work. Now that you include the show notes it takes me the whole week to sift through all the cool stuff but it's generally worth it.

Larry

madboar
2007-Mar-08, 01:57 AM
Hey guys,

Just listened to the show - it was as good as ever. Thanks!

This weeks show reminded me of a recent APOD showing the galaxy cluster showing Abell 2667.

Its got a great example of galaxy 'harassment' (haha - a new one for me!) and some lovely lensing. What a picture. How we're gonna miss hubble!

http://antwrp.gsfc.nasa.gov/apod/ap070305.html

Might be worth adding to show notes?

Anyway, thanks again. Looking forward to next weeks show.

Andrew (Belfast, Northern Ireland)

Galaxy
2007-Mar-08, 06:08 PM
Hey guys,

This weeks show reminded me of a recent APOD showing the galaxy cluster showing Abell 2667.

Might be worth adding to show notes?


Andrew,

I just added a "pretty pictures" category to this week's show notes. I try to include a bunch of cool pictures in the HTML version of the transcript (below the show notes) but now I've linked to some of the sites that I get those pictures from so you can browse to your heart's delight!

-Rebecca
Astronomy Cast student worker

Varg
2007-Jun-21, 07:49 PM
just got around to listening to this episode. good stuff but...Milkdromeda?

skrap1r0n
2008-Mar-21, 01:03 AM
ok I have listened to the first 32 podcasts and this episode is the one that I have a question about. I am asking this from a point of knowing I do not understand a lot, but here goes...

Why do super large galaxies have an elliptical shape and smaller ones are disc shaped?

Here is why I ask, the milky way, for example is spiraling around a super massive black hole, so is the Andromeda Galaxy. Systems within the Galaxies have stars rotating around stars, planets rotating around stars, black holes consuming gas in a spiraling accretion disk etc. The effects of angular momentum is readily apparent on scales as small as a planet/moon relationship, all the way up to our galaxy.

So why is it, that large galaxies lose this trait? For that matter, why are galaxies clustered in a sponge-like pattern instead of in an ever larger spiral? Is there an upper bound on the effects of angular momentum and ultra-large collections of mass or has there just not been enough time for these effects to take place? Or maybe they HAVE taken place but it hasn't reached us yet?

Also, in a similar vein, why are globular clusters not disk-shaped? what is it about their structure that keeps them from spinning up around a denser core group?

Awesome podcasts, by the way. I love this series, and have to say that Fraser and Pam discuss things on a level that isn't too high fr a layman such as myself to understand.

Clegrand
2008-Mar-21, 12:02 PM
Can't help with clearing up your dilemma, however I recently learnt of informal experiments done in space. These experiments took granular materials such as sugar in a bag filled with liquid in zero gravity...

(would the gravity be zero? I mean there is mass? No matter, that question can be for another day)

...and watched how the sugar granules interacted. This helped give another theory of how our Solar System formed, maybe it could also be a small link to understanding the formation of larger structures such as the supercluster formations.

Oh, I also wish to add my compliments to the podcasts! I am seriously hooked, great work Frasier, Pamela and Rebecca!