Click here if you are having trouble logging into the forums
Privacy Policy |
Please read our Terms
of Service | Signup and
Troubleshooting FAQ | Problems? PM a Red or a Green Gu.... uh, User
FirstSight
Carpal Tunnel
   
Reged: 12/26/05
Posts: 2522
Loc: Raleigh, NC
|
Re: The vast "empty quarter" east of Sagittarius
07/28/08 05:34 PM
|
|
|
Quote:
We're sitting in the middle of a cosmic web of matter. Long filaments and vast voids. These "empty" regions of the sky simply represent areas where we are looking out into one of the voids in the universe. With medium and large telescopes you can see galaxies on the other side of the void, and these relatively "sparse" regions fill in. In fact, as a large telescope user, I consider Bootes, Capricornus, and Cetus as rather fertile ground for distant galaxy observing. Many of these galaxies aren't very distant at all, only a few hundred million light years, if that. In fact, as long as there isn't the milky way in your way, you can see huge numbers of distant galaxies in every constellation with a large telescope.
From the outset I understood that on the grand macro scale of things, the universe is similar in every direction, but as you reduce to the finer scale of individual galaxies and galaxy clusters, the local distributions become more filamenty and lumpy, with relatively sparse regions in-between. And so, yes if you proceed far enough in any given direction, there's stuff out there, just not much that's particularly near, bright, or accessible without larger telescopes and dark sky sites, unless you're looking in a direction either toward a nearby filament, or within your own galaxy.
My question was directed at making sure I understood the correct reasons why the region toward e.g. Capricorn and Cetus appeared to be relatively sparsely filled with more easily accessible objects, versus e.g. the UMa region, when both are in a direction away from the plane of our own galaxy. More from a trick of perspective and obstructed vision, or more from a true relative void in that direction for quite a distance?
-------------------- Chris M., aka "First Sight"
Orion XT12i Dob with Moonlite CR-2 focuser
WO Megrez 90 refractor on UniStar Light mount
Nikon 10x50 Binoculars
Edited by FirstSight (07/28/08 05:54 PM)
|
|
1 registered and 2 anonymous users are browsing this forum.
Moderator: matt, Olivier Biot
|
Forum Permissions
You cannot start new topics
You cannot reply to topics
HTML is disabled
UBBCode is enabled
|
Rating:
Thread views: 444
|
|
|
|
|
|
|