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[Chicago Astronomer - Astro Joe]

Eta Carina gives Earth Observers it's Opinion of us

It's a great image from the Hubble.

I wonder...if it would be just as we see it here if we were aboard a space craft looking at it thru a porthole. Probably not. I would imagine it would be darker and not that impressive, considering the Hubble must have taken a very long exposure of the nebula and gathered more light than than we would normally observe.

[Maddad]

antwrp.gsfc.nasa.gov/apod/ap000613.html
Just out of curiosity, I looked up the Keyhole at APOD. My guess is that this image is close to what you would actually see from a spacecraft. Don't see the finger anywhere, so I'll keep looking.

antwrp.gsfc.nasa.gov/apod/ap990523.html

antwrp.gsfc.nasa.gov/apod/ap970721.html
Ah, there's the finger!

antwrp.gsfc.nasa.gov/apod/ap960404.html
Slightly visible here too, now that you know what to look for. Older pic, so it's not as good.

[Chicago Astronomer - Astro Joe]

Dave,

Thanks for the links.

In visible light astronomy, we see mostly varied shades of grey in the eyepiece. The astronauts said that in space there is absolutely no color, other than the Earth and Moon. I wonder if that's what awaits us, as future spaces travelers, 90% blackness with few interesting targets to focus on, far in between and bland....quite boring.

So I wonder, let's say we head out to the Andromeda galaxy. As we approach, would we see the typical disk, with brightly lit spiral arms and a bright central bulge? Or seeing it in real time with naked eyes, just a faint mist - like in the telescope, that starts to lose it's shape as we get closer and enveloped within it, starting to focus just on the brighter stars. There must be a point where we lose our perspective of the whole, and do not even realize we are in a distant galaxy.

I always had thought that the arms of our galaxy should be more prominent in our skies, despite the dust lanes and light pollution. Perhaps if we were in closer to the central bulge the skies would be brighter with galatical objects. And you gotta wonder if there are inhabitants near the bulge, if it would rise like a sunrise, casting shadows and screwing up their body clocks.

Thoughts that run through my head...when I wear my aluminum hat...

[Maddad]

It's an interesting question, Joe. I suspect that the astronauts didn't see color partially because they didn't bring their 14" scope with them from their back yard. When I look up into the night sky, I don't see much color except in a few cases like Mars or Saturn. It's terribly light poluted here. Maybe good color is an issue of resolution. What do you think?

[Chicago Astronomer - Astro Joe]

I'm sure resolution plays a part in color perception, but even without it, the cones and rods of our eyes should pick up the subtle variances.

Now, lunar images taken with our many scopes and instruments look pretty much like what we see with our naked eyes. But really, there isn't much color there other than varying shades of grey. But I wonder what it will look like to the naked eyed astronaut peering thru the porthole at the Orion nebula for example. Will they see the many colorful tendrils that that we have come accustomed to? I don't think so. Without the accumulative properties of film and ccd's, I think that it may appear like grey wisps with minor colorations...

Gee, I hope I am in error in my perceptions.