by Chris Peterson » Tue Mar 27, 2012 4:50 am
TNT wrote:jisles wrote:The galaxy is not 'towards' the constellation Ursa Major. APOD captions regularly make this mistake. It's IN the constellation Ursa Major. Constellations comprise everything within an irregularly-outlined cone, stretching to infinity, whose apex is at the observer's eye. I love APOD though!
That seems correct to me. If an object is said to be in a certain area, wouldn't it also be seen
towards that area? And where are you getting an irregularly outlined cone? It would be more logical to say that it is an irregularly shaped figure or plane, as it appears two-dimensional. I don't think I've even seen an irregularly outlined cone before.
As I noted, a cone is not limited to a solid with a circular base- the base can be any polygon, and calling that shape "an irregularly outlined cone" seems clear enough. Technically, an object is always "in" a constellation, not "towards" it. And that means that the object lies in the volume defined by the so-called irregularly outlined cone. Personally, I don't have much problem with a caption that says something is "towards" a constellation, but that usage isn't very conventional.
[quote="TNT"][quote="jisles"]The galaxy is not 'towards' the constellation Ursa Major. APOD captions regularly make this mistake. It's IN the constellation Ursa Major. Constellations comprise everything within an irregularly-outlined cone, stretching to infinity, whose apex is at the observer's eye. I love APOD though![/quote]
That seems correct to me. If an object is said to be in a certain area, wouldn't it also be seen [i]towards[/i] that area? And where are you getting an irregularly outlined cone? It would be more logical to say that it is an irregularly shaped figure or plane, as it appears two-dimensional. I don't think I've even seen an irregularly outlined cone before.[/quote]
As I noted, a cone is not limited to a solid with a circular base- the base can be any polygon, and calling that shape "an irregularly outlined cone" seems clear enough. Technically, an object is always "in" a constellation, not "towards" it. And that means that the object lies in the volume defined by the so-called irregularly outlined cone. Personally, I don't have much problem with a caption that says something is "towards" a constellation, but that usage isn't very conventional.