I think that question would be answered by the resolution of the view.  Lava
would tend to be in the lower light wavelengths (red & orange) where
"lights" would be a wider band, toward white (unless they see in infrared or
UV).  Also, volcanos would have a "star" pattern with a center and radii,
and lava flows would look like rivers (but be rather short).  Our cities
tend to form "blocks" of square patterns, and the length of illumination of
roads is much longer than lava flows.

-- Stinger

"Mr. 4X" <random.wvu@ivc.invalid.com> wrote in message
news:Xns9448E1F9CEC0Emr4x@195.228.240.20...

"Stinger" <contact@newsserveronly.com> wrote in message
news:vdPzb.638$E7.352@bignews5.bellsouth.net:

There's a great scene in the movie "Contact" during the "wormhole"

sequence

where the capsule stops very briefly above a planet orbiting Vega.  It

shows

patterned lights on the dark side of the planet.  The dialogue:

"They're

alive...."  Whoosh!

Yeah.

I wonder how a volcano with lots of lava in the crater on the night
side looks from a few 100 kms - is the glow of the lava visible at all?

-- Stinger

"Mr. 4X" <random.ay@hf.invalid.com> wrote in message
news:Xns9447E1992E621mr4x@195.228.240.20...

"Stinger" <contact@newsserveronly.com> wrote in message
news:Jdtzb.1645$MY2.383@bignews6.bellsouth.net:

Bingo.

Yes, they could be easier to notice then the radio transmissions. Even

if

the visitors don't use city lights and haven't any yet: they could

think

it's a weird volcanic phenomenon...

"Mr. 4X" <random.zhoan@dbbom.invalid.com> wrote in message
news:Xns9446E4D4A4373mr4x@195.228.240.20...

What about the city lights?