Although looking serene to human eyes, the night sky appears as a spectacular cosmic firework display. These fleeting phenomena, known as astronomical transients, reveal them across the whole electromagnetic spectrum. A large fraction of these transients are canonical supernovae (SNe) or other exotic stellar explosions. Unraveling the intricacies of how these explosion phenomena emerge and identifying their celestial sources has become one of the focal points in modern time-domain astronomy, which can reveal a great deal about the universe, from how matter and force behave in the most extreme conditions to how the cosmos evolved.
In this talk, I will talk about recent observational progress in understanding the final explosion of stars, including thermonuclear explosion of white dwarfs, core-collapse of massive stars, and the new emerging population of fast-evolving transients with unknown origins. I will discuss observations spanning from the initial moments shortly after the explosion to very late times. I will show that observations in different phases of the transients allow us to probe different aspects of the explosion phenomena. For example, the infant phase probes the ambient environment and nebular phase penetrates the innermost ejecta of the explosion. In this talk, I will highlight two recent discoveries, I will highlight two recent discoveries, the periodicity in a stripped envelope SN 2022jli and the minute-duration optical flare in the late time of a luminous fast blue optical transient AT 2022tsd, which show the importance of the newly formed compact object (neutron star or black hole) in the aftermath of stellar explosion.
