can't see faraway galaxies

General discussion about Celestia that doesn't fit into other forums.
Topic author
billc

can't see faraway galaxies

Post #1by billc » 13.06.2003, 00:25

Hello!
I'm trying to observe galaxies from Earth, and I've just discovered that anything more than about 1.25e7 lightyears away doesn't show up at all in the sky. Too bad! Any way around this?

Guest

Post #2by Guest » 13.06.2003, 00:29

There's a limit around 16ly...I think.

Avatar
selden
Developer
Posts: 10192
Joined: 04.09.2002
With us: 22 years 3 months
Location: NY, USA

Post #3by selden » 13.06.2003, 01:57

Anonymous guest,

the 16K limit is only for drawing stars.

Guest billc,

How did you determine that you couldn't see galaxies beyond 1.25e7 ly?

The "galaxies_extended.dsc" addon defines galaxies more distant than that. NGC 5839 is at a distance of 7.6e7 ly, for example. I have no trouble seeing it on my system. The "galaxy_clusters.dsc" addon includes clusters of galaxies at distances greater than 3e9 ly. I have no problems seeing the blob representing the cluster A895 at 3.887e9 ly, either telescopically or by going there.

These catalog files are available in http://www.lns.cornell.edu/~seb/celestia/galaxies.zip

added slightly later:

3DS models of galaxies can be seen at greater distances, too. There's a crude model of NGC4622 available in http://www.lns.cornell.edu/~seb/celestia/ngc4622-4.zip. Its DSC file places it at a distance of 111e6, which is the same as 1.11e8. It's quite visible on my system, else I would have screamed about it long ago.
Selden

Topic author
billc

Post #4by billc » 13.06.2003, 15:03

Thank you both for your prompt replies. And thank you Selden for all the galaxy and cluster info (and everything else!) you've provided. I have no problem seeing the galaxies in your list if I go to them, but if I try to see them "telescopically", they're not in my sky unless I approach them. At about 1.25e7 light years away they suddenly pop into view. If I back up (increasing the distance), they pop out of view. Judging by your response, I guess it isn't the program. Is it my computer system?


Return to “Celestia Users”