Evening (or rather, early afternoon here). I also entertained the idea that he could mean "I am a sunburst," or for that matter "I am a burst of sunlight"--but figured that if that's what he meant, he should have damn well said it. Frankly, in the context, exactly what he thinks he is is less important than the Master's question about "who is perceiving it?"Detto questo, non so se intendono riferirisi ad un sole splendente (sunburst) oppure al brillamento solare/stellare (solar flare).
Evening arti. I wouldn't associate it with the rising sun either.