The Sons of Earth was an organisation of humans during Earth's Imperial period. They were opposed to the colonisation of other worlds, the exploitation of their resources, the disruption of native peoples and the destruction of native ecosystems.
It was believed that the constellations were studied by Kasterborous from Earth's perspective due to pressures from this group. (PROSE: Short Trips: Zodiac)
Rohm-Dutt pretended to be working for them, supplying guns to the Swampies, when he was in fact an employee of Thawn, the leader of the methane refinery on Delta III. Thawn hoped that the Swampies would attack the refinery, justifying their extermination. Rohm described the Sons of Earth as a "crank" organisation that wanted all humans to return to Earth and starve. (TV: The Power of Kroll)
They were still active in the 34th century, (PROSE: The Dark Path) and the 51st century. (TV: The Power of Kroll)