 How do Svan and his five fellow insurgents find out that the people of Earth no longer think of

Venusians as human?
DOUBLECROSS by JAMES Mac CREIGH Revolt was brewing on Venus, led by the descendant of the first Earthmen to land. "They had to acclimate themselves to Venus's climate. The native guard of honor, posted a hundred yards from the Earth-ship, stood stolidly at attention with their old-fashioned proton-rifles slung over their backs. They think there will be hordes of immigrants from Earth, now that we know Venus is habitable. And there's some sort of a paltry underground group that is spreading the word that the immigrants will drive the native Venusians—the descendants of the first expedition, that is—right down into the mud. We have agreed that, if the Earth-ship returns, it means disaster for Venus.
 They use a spy ray, which allows hem to listen in on a conversation happening on an official
 They are informed by fellow Venusian rebels, who themselves heard from the council.  They already know. Racism and prejudice runs rampant in all Venusian and Earth towns.  They intercept a galactic transmission, which explains it all.  They use a spy ray, which allows hem to listen in on a conversation happening on an official