The planet was almost identical to Earth, orbiting its sun at about 149,3 million kilometers distance. However, its axial tilt was only nine degrees, and it had a slightly higher percentage of landmass than the human homeworld. (CS2)
The climate was so mild that most "natural disasters" reported in Mesan news were actually man-made, like fires. (CS3)
Due to the low axial tilt, Mesa's average temperature was somewhat higher and the seasonal variations quite a bit smaller than on Earth. Large parts of the surface never experienced any snowfall. (CS2)
Mesa was settled in 1460 PD by a group of renegade Beowulfans, led by Leonard Detweiler, who rejected their old homeworld's restrictions on genetic engineering of humans. Thus, the planet soon became the headquarters of several, widely reviled as morally and criminally bankrupt, corrupt, and corrupting trans-stellar corporations.
In secret, it also became the headquarters of the Mesan Alignment, a covert organization of genetically "enhanced" humans with the ultimate goal to take over the colonized universe. (CS2)
In late 1922 PD, Operation Houdini saw the move of all of the Alignment's remaining assets from Mesa to the Darius System. When the Grand Alliance invaded the Mesa System, Albrecht Detweiler personally activated a series of nuclear warheads, killing himself and all remaining Alignment personnel, as well as any signs that there ever was a secret shadow government on the planet Mesa. (SI4)