Superman's powers and abilities are scientifically possible.

You state: "Superman is an alien from the planet Krypton. Now, according to Earth science, there will be some issues regarding the possibility of these powers, but I must point out that aliens will have different technology, different DNA, and different abilities. "Unfortunately for Superman, the laws of physics are universal. You mention "Earth science" as if the laws of physics differ from planet to planet. This is most certainly not the case.It is true that aliens may have different technology, different DNA, and different abilities. But it is NOT true that these abilities would include the ability to defy the laws of physics. Furthermore, Superman's abilities have absolutely nothing to do with technology. So your point about aliens having different technology is a moot one.Superman would have different DNA, and he would have different abilities. But no one can argue the point that his form is anthropomorphic. Regardless of origin, something in the shape of a human (other than a human-shaped balloon) cannot fly. Superman is not a helium-filled balloon. Therefore, the laws of aerodynamics and buoyancy are enough to state that Superman's ability to fly is scientifically impossible. There is no possible DNA sequence that would allow for an anthropomorphic entity to fly, alien or not. Defying the laws of physics is not an alien ability-- it is an impossibility! To add to this, Superman does fly on the planet Earth. This means that even if the planet Krypton contained different laws of physics (which it would not), the laws of physics here would still be applicable. Superman's ability to fly is a clear defiance of the laws of physics and is scientifically impossible.As far as Superman's heat vision is concerned, we need to understand how the eye functions. The light is focused through the cornea, which must be transparent to allow light through. Behind the cornea is the iris, containing the pupil which adjusts in size to allow for a greater or smaller amount of light to pass through. Between the cornea and iris is the aqueous humor (clear fluid in between). Behind the pupil is the crystalline lens (also transparent). [1]There are many more components of the eye that I will not describe. But the main point is that vision requires light. In order for light to be received, the structures of the eye must be transparent! Alien origins and completely different DNA cannot change the laws of optics.Any structure thick enough or strong enough to withstand Superman's heat vision must be opaque! Superman may be an alien from another planet, but regardless of his origins, anything that is thin enough to allow for vision would be too thin to withstand Superman's heat vision. What it comes down to is something has got to give. Either an alien that can shoot heat beams would not be able to use the same organ for sight, or the organs used for sight cannot shoot intense heat beams. Even something that is transparent would eventually become translucent, and finally opaque as more and more layers are added to make it strong enough for a heat beam.Regarding Superman's super speed, I pointed out that the animals designed for fast speeds are all quadrupeds. Superman's body is in the shape of a human. Such a form is simply not designed for super speed. As far as this ability goes, I will grant that alien origins could account for initial super speed. An alien from a massive planet (e.g. Jupiter) would have to develop muscles and functions to cope with the extremely large gravitational force. When taken from one planet and placed on another much lighter planet, the evolutionary advancements would allow for a faster running speed and a higher jumping height.However, these abilities would diminish rather quickly over time. As can be shown by the astronauts, when the muscles are no longer being used to combat gravity, they naturally weaken. [2] In Superman's case, if Krypton was a massive planet, his muscles would initially be stronger. But as a living organism, he too would be subject to biological processes. So without fighting a large gravitational force on a daily basis, Superman would lose his super speed fairly quickly. In fact, this would have probably been almost completely diminished by the time he arrived on Earth, considering the long journey.In summary, Superman's abilities defy the laws of science. Alien origins and alien DNA cannot change physical law.[1] http://www.livescience.com...[2] http://www.nasa.gov...