Most estimates I've seen have it around 600 LY away.
"When a star goes bang, the first we will observe of it is a rain of tiny particles called nuetrinos.
I have more confidence in someone who can spell "neutrinos" correctly. Would you trust a cardiologist who wanted to talk to you about haert surgery?
I don't know how Mr. Carter knows that the Earth is safe, but I'd like something a little more concrete.
Gamma ray bursts are the killers and they follow the poles of the supernova. Betelgeuse's pole isn't pointing at us.
In the year 1006 there was another supernova, SN 1006 that was visible on earth for two days. It was called a "guest star."
A lot longer than that. The original author was probably confused by the wikipedia entry "First appearing in the constellation of Lupus between April 30 and May 1 of that year," which simply tells the first night it showed up on, not its total duration of visibility. Later in the same article it states "There appear to have been two distinct phases in the early evolution of this supernova. There was first a three-month period at which it was at its brightest; after this period it diminished, then returned for a period of about eighteen months."
As for a "second sun", Betelgeuse's supernova would likely be about half as bright as the full moon. Impressive? Yes, very. But not a second sun.
It is the Red Giant in Orion. It takes 1300 years for the light to reach Earth. It has already exploded if he is right. Over a thousand years ago.