OK, back on topic.
If Betegeuse does go nova, the light from it would be at a brilliance somewhere between the full night moon and the sun on a cloudy day, which means for a year or so, the earth will be bathed in plenty of light by a third celestial object, one that moves in relation to the near universe, rather than annual or monthly variation.
The invisible cosmic radiation will appear at roughly the same time as the event, meaning that many satellites will get a severe battering from X/gamma rays. Manned flight into space will need to be overhauled, and the ISS crew may need to take shelter in the more shielded parts for about 20 minutes every hour.
Any real particles from Betelgeuse will take some 50,000 years to reach us, but there should be some constant (and decent) meteor showers daily for everybodys offspring.
One last piece of information, Orion may look like a close group of stars, but these are all at different distances to the earth. Additionally within the constellation there are nebulae containing containing groups of stars which appear as one to the eye.
If one was to use the distance of your computer monitor to your eye (about 80cms or so), as the distance of the sun to the outer planets, the Orion constellation as we know it would extend from about 80 to 280 miles away, or between Newbury and Penzance if viewed from London.
It may be close in galactical terms, but its not particularly close with the spacecraft we currently use to get off this planet. Voyager has so far taken thirty years to get just over a yard, even with help from 'swing-bys'.
