Starship Asterisk*

http://apod.nasa.gov/apod/ap090109.html

Are all the stars we see with this image in the Milky Way? (except for the distant galaxies of course)

emc wrote:http://apod.nasa.gov/apod/ap090109.html

Are all the stars we see with this image in the Milky Way? (except for the distant galaxies of course)

Yes...although sometimes it is difficult to separate the stars from the galaxies:

NGC 4976: Located a little over 3 degrees from the large southern spiral NGC 4945, this inconspicuous little elliptical galaxy was nevertheless detected with a 5" telescope working at 20x magnification by comet hunter Jack Bennett. The bright star on the right is SAO 223931 and shines at mag 7.8

neufer wrote:

NGC 4976: Located a little over 3 degrees from the large southern spiral NGC 4945, this inconspicuous little elliptical galaxy was nevertheless detected with a 5" telescope working at 20x magnification by comet hunter Jack Bennett. The bright star on the right is SAO 223931 and shines at mag 7.8

I assume the the bright star on the right is to the left of NGC 4976 in the APOD.

Hey, Ed!

neufer wrote:

emc wrote:http://apod.nasa.gov/apod/ap090109.html

Are all the stars we see with this image in the Milky Way? (except for the distant galaxies of course)

Yes...although sometimes it is difficult to separate the stars from the galaxies:

That is what I thought... Nice to have support! Thanks!

bystander wrote:

neufer wrote:

NGC 4976: Located a little over 3 degrees from the large southern spiral NGC 4945, this inconspicuous little elliptical galaxy was nevertheless detected with a 5" telescope working at 20x magnification by comet hunter Jack Bennett. The bright star on the right is SAO 223931 and shines at mag 7.8

I assume the the bright star on the right is to the left of NGC 4976 in the APOD.

Hey, Ed!

Howdy, bystander!

Your pointing out the directional disparity brings up a point I recall someone else mentioning here regarding the orientation of space images. I reckon it would be nice for us beginners to have standard views based from the northern hemisphere like our typical earth maps. But that's more complicated than asking everyone to use the metric system... (and we know how that goes) And I reckon northern perspective conformity would require the folks in the southern hemisphere to turn their cameras upside down. Getting everyone to align their images with the celestial poles would require some sort of new world political order. Or perhaps a Borg invasion assimilation... Scarry to think about...

emc wrote:Your pointing out the directional disparity brings up a point I recall someone else mentioning here regarding the orientation of space images. I reckon it would be nice for us beginners to have standard views based from the northern hemisphere like our typical earth maps. But that's more complicated than asking everyone to use the metric system... (and we know how that goes) :wink: And I reckon northern perspective conformity would require the folks in the southern hemisphere to turn their cameras upside down. :?

It is conventional in astronomical imaging to present images north up, east left. This convention is applied regardless of whether the image was made in the north or south hemispheres.

However, many amateurs use self guided cameras. These have the guide sensor fixed in relation to the main image sensor, and it is often necessary to rotate the camera to some arbitrary position in order to find a guide star. Also, cameras used by amateurs usually have rectangular dimensions, so non-standard orientations are sometimes chosen for aesthetic reasons. Occasionally images are made with optics that reverse the image. This is particularly confusing when the image processor neglects to mirror the result.

IMO any image that doesn't follow the north up convention should have its orientation described in the explanatory text.