Those are not supernovae, which brighten and fade over a span of weeks. (The energy input of core-collapse supernovae is the radioactive decay of Nickel-56 (hal

Those are not supernovae, which brighten and fade over a span of weeks. (The energy input of core-collapse supernovae is the radioactive decay of Nickel-56 (half life 6 days) and Cobalt-56 (77 days).) Edit: those may have been Iridium flares that you saw.