Dave Lillis asked how far away the event is.
I think they stated during the broadcast that it was approx 26,000 Light years away -towards the centre of the Galaxy.
In the direction concerned there is quite a lot of dark material along the line of sight, hence even though the event would have been spectacular the poor optical path meant the initial opitical effects were not obvious in 1890-1900 (I think that was the epoch they mentioned).
Chandra spotted the X ray element some time ago and then had it confirmed as lower RF freuencies by an earth based observatory.
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