As a subject matter expert on the fictional universe of DC Comics, particularly the lore surrounding the character Superman, I can provide a detailed answer to your question.

In the mainstream DC Comics continuity, Kryptonians do not possess superpowers on Krypton. The reason for this is that Krypton's gravitational pull, atmosphere, and radiation levels are different from those of Earth. On Earth, these differences allow Kryptonians to photosynthesize the yellow sun's rays, which in turn grants them their extraordinary abilities.

However, it's important to note that there are variations in this concept across different storylines, alternate universes, and adaptations. For example, in some versions of the story, Kryptonians are depicted as having a higher level of natural strength and resilience compared to humans, but not the full range of superpowers that they exhibit on Earth.

Additionally, Kryptonian technology is often portrayed as highly advanced, and some Kryptonians may have abilities or powers derived from their technology rather than any inherent biological advantage.

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Most tales now have Superman gaining his powers as an adult after years of exposure to solar radiation. This however does not explain the rapid speed that most Kryptonians seem to gain their powers once exposed to the yellow sun of Earth.read more >>