Talk:SN 2008ha

Dating the explosion
Hi people. Ok, so I'm an astronomy ignoramous, but I'd like to know what the convention is for dating astral events. The text here states that "SN 2008ha was a type Ia supernova which exploded around November 7, 2008". My query is that, as it is 69 Mly away, surely it actually exploded some time in the late Cretaceous? November 2008 is just when it became visible from Earth.  Pyrop e  15:52, 11 September 2009 (UTC)
 * The important point is when it became visible on Earth. Kinda hard to dinosaurs to observe SNe... Modest Genius talk 15:57, 11 September 2009 (UTC)
 * Very true! But my point was mostly with the language used. It seems to suggest that the explosion actually took place last year, not just that that was when our species observed it.  Pyrop e  16:59, 11 September 2009 (UTC)
 * They may as well be the same thing. Before we saw it, it was beyond our light cone horizon, and therefore effectively outside our universe. It's a subtle point, and honestly I wouldn't expect anyone to understand what I'm on about unless they've studied some general relativity. Suffice to say, in professional astronomy this is the universal usage. Modest Genius talk 20:36, 11 September 2009 (UTC)

I've changed it, this time to "first observed on" which should satisfy everyone and sounds better than "seen to explode". --Falcorian (talk) 22:19, 11 September 2009 (UTC)