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> When that happens, the resulting explosion will be visible from Earth, even in broad daylight. How much visibility are we talking about?
by 0xFFC 9y ago
> When that happens, the resulting explosion will be visible from Earth, even in broad daylight.
How much visibility are we talking about?
- aruggirello 9y agoIIRC we're talking about it reaching apparent magnitude ~ -12, given or taken a couple magnitudes (or about as bright as the full Moon - Just imagine that much light coming from an infinitely tiny dot instead). BTW with a declination of ~ +7° Betelgeuse is very close to the celestial equator, so the supernova will be visible from anywhere on Earth, save a very small region within 7° from the South Pole.
- dahart 9y agoIt's fun to ponder how it will be that bright at every point that is the same distance. Imagine a sphere centered on Betelgeuse with a 600 light year radius with Earth on the surface of this sphere. The fact that enough photons reach my eyeballs to be able to see it at night is difficult to comprehend - the amount of energy needed to sprinkle every square millimeter of a sphere that size is just unimaginable. Now make that 100,000 times brighter during a supernova event -- crazy town. I feel like imagining the energy from a star spread out on a galactic scale helps me understand and appreciate the magnitudes better than any large number of luminosity or watts or photos can.
- theandrewbailey 9y agoRigel, the blueish star on the other side of Orion, is a bit brighter (magnitude 0.13 vs. 0.5), and is a bit further away (860 ly vs. 640).