Astronomy inside a globular cluster

If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.

--
Craig Franck

Cortland, NY

I think you're asking this question because you feel that a globular cluster
is so crowded with stars that you would be hampered in seeing anything
outside of the cluster. I'm not sure that it's as crowded as it appears to
be. I remember reading once that a cube of space 2 light years with each
leg and situated in the center of a globular cluster would contain only 2
stars. This leaves a lot of space between stars.

Al


"Craig Franck" wrote in message
...
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.

--
Craig Franck

Cortland, NY

"Craig Franck" wrote in message
:

If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.


A globular cluster would allow clear sight to the outside (at least from
orbit). Same thing for an elliptical galaxy. The nebulas and other
structures (parts of the home galaxy and other galaxies) outside would be
visible from a globular cluster. I really doubt that those things, even if
they would be a lot dimmer than the nearby stars, would be unnoticed, at
least by scientists. The inside of a larger interstellar nebula would be a
lot 'worse'.

(BTW I think the night sky could be a lot more beautiful in a globular
cluster or near a large nebula...)

"Craig Franck" wrote in message . ..
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.

With the brightness of stars being so close, you'd be lucky to see
anything outside the cluster if you were in it.
-Rich

"Craig Franck" wrote in message . ..
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.

A) it is thought that the orbital motions of stars in GCs or EGs are
not as conductive to platetary formation and planetary survival than
spiral galaxies. This would be cripling because you couldn't be there
to observe.

B) having a bunch of bright lights at night would make early astronomy
easier (think pre-telescope time) as there are more bright things to find
and measure. However, finding other things might be harder since a dim
object close to those bright objects would require better telescopes.
So it is unlikely Messier-kin would have compiled a list of stuff.

C) after the advent of big ground telescopes or space born telescopes,
lots of bright close objects no longer remain a serious handicap to
scientific astronomy. Amateur astronomy would be affected in unknown
ways.

In sci.astro.amateur Al wrote:
I think you're asking this question because you feel that a globular cluster
is so crowded with stars that you would be hampered in seeing anything
outside of the cluster. I'm not sure that it's as crowded as it appears to
be. I remember reading once that a cube of space 2 light years with each
leg and situated in the center of a globular cluster would contain only 2
stars. This leaves a lot of space between stars.

Yeah, it's surprising how empty the sky of a globular would be. Even
for a million-star cluster, and if you could see all the members
down to red dwarfs, that would only be about 25 stars/square degree.
The sky from an Earthlike world would be pretty bright, with all
those Venus-magnitude stars floating around.

And from either a globular or an elliptical galaxy, we'd eventually
figure out that there are distant galaxies. That would either come
from learning to do radio and X-ray astronomy (which would discover
active nuclei and galaxyt clusters), or launching the Hubble-analog,
which would start to see diffuse sources between the stars. It would
be really curious to imagine a species discovering the redshft-distance
law from X-ray measurements of galaxy clusters without necessarily
having observed the constituent galaxies...

Bill Keel
(quite satisfied with the messy disk of a spiral, thank you)

"Craig Franck" wrote in message . ..
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole?

Someone has to mention the classic science fiction short story
"Nightfall" by Isaac Asimov in this thread, so I might as well do it.
It's about astronomers living on a planet in a six-star system inside
a globular cluster.

"Craig Franck" wrote in message
...
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.


Presumably for astronomers inside a globular cluster, the Miky Way would be
a large, faint, diffuse object that would undoubtedly have some important
mythological significance, especially if "face on" so its spiral structure
is visible. It would probably be quite a profound moment when the first
telescope revealed it to be made of stars!

Perhaps though that would be a quick kick-start to a deeper understanding of
cosmology. It would then be easy to see that the other globular clusters are
similar to one's own and that they are bound to the galaxy. Then a quick
search of the sky would show other galaxies e.g. the Andromeda Spiral. Our
own astronomers were stuck for some time before anybody realised we were
inside a dense, localised patch of stars in a largely empty and impressively
huge universe (less than 100 years ago!). That would be much more obvious
perhaps to our globular cluster astronomers.

Ian

William C. Keel wrote:

In sci.astro.amateur Al wrote:

I think you're asking this question because you feel that a globular cluster
is so crowded with stars that you would be hampered in seeing anything
outside of the cluster.

I vaguely recall seeing a painting whose viewpoint was from a planet
orbiting a star in a globular cluster. Might have been Chesley Bonstell
(sp?). Of course there's no guarantee of accuracy, painters may take
liberties; and I imagine there is room for disagreement as to how things
would look.

Mike Maxwell

"Craig Franck" wrote in message . ..
If earth were inside an elliptical galaxy or near the center of a large
globular cluster, would that more or less cripple any attempts to
study the universe as a whole? I imagine that stars would be fairly
evenly distributed, there would be very little interstellar matter, and
the few other galaxies visible would be composed mostly of the
local group.

I think the May 11, 2004 image of M13 with its many small fine blue
stars surrounding the core of the globular cluster might give some
clue as to how dense the star field might be seen. In any case, WOW,
just imagine the stories and legends that would be told to account for
the night sky as seen from a planet imbedded in this beautiful
cluster.

http://antwrp.gsfc.nasa.gov/apod/ap040511.html

Click on the image to get the large version, then notice the thousands
of faint blue stars visible in the image. Like grains of sand on a
beach. What a wonderful magnificent sight that night sky would be!

-sh