The electromagnetic spectrum is the collective term for all possible frequencies of electromagnetic radiation.
A star is a luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun. Other stars are visible to the naked eye from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth.
The habitable zone (HZ), is the range of orbits around a star within which rocky planets with sufficient atmospheric pressure can support liquid water at their surfaces.
In astronomy and physical cosmology, the metallicity is the fraction of mass of a star or other kind of astronomical object that is not in hydrogen or helium.
A supernova is an astronomical event that occurs during the last stellar evolutionary stages of a massive star’s life, whose dramatic and catastrophic destruction is marked by one final titanic explosion.