The film's official novelisation covers this. It's a bit wordy, so bear with me.
The Europeans
What happened in 1998, at Alpha Space Station in orbit around the
blue-green world, was not merely two nations meeting. When the
European Hermes spaceplane, proposed in the same year as that first
historic handshake, arrived to dock at Alpha, it represented a
coalition of nations. Space was no longer the province of a few tiny
humans, but was rapidly evolving to belong to humanity.
The Chinese
The space station grew as time went by. In the year 2019, China’s
massive Tiangong-3 spaceship was warmly welcomed when it came to take
its place at Alpha. The captain of the Alpha Space Station, one
thirty-year-old James Crowford, enthusiastically greeted his Chinese
counterpart Wuang Hu, who himself could not seem to stop smiling.
Later historians would mark this moment as the end of international
tension, and the beginning of what was the first Great Age of human
cooperation.
Pretty much everyone else
More nations had ventured into the stars, and wanted to be part of
this symbol of unity. By 2029, every country on this third planet from
the sun had at least one scientist on board to represent them.
In 2031, an artificial gravity system was installed. The station’s
denizens could now walk its corridors as easily as they walked on
their home planet. Captain Crowford was now a distinguished man of
forty-one years. He had the honor to welcome captains from India, the
United Arab Emirates, Korea, Africa, Australia, Brazil, and Japan—
who, instead of the iconic “handshake in space,” offered and accepted
a traditional bow.
The Kortân-Dahuks
Three aliens stepped from their ship onto Alpha station.
They were slightly taller than their human hosts, and were roughly humanoid—“Such a telling, Earth-centric word,” lamented Norton, “and we still don’t have anything better”—but there the similarities ended. Norton and his fellow delegates recognized arms and legs, heads with eyes and mouths, but these were appendages affixed to reptilian bodies, and eyes and ears on faces without noses.
Their primary skin color was orange, with blue, yellow, and red blending in those large, noseless faces. Protruding blue-gray lips were set in hard lines. They wore armor on their torsos, lower arms, and legs, and their feet ended in what looked to human eyes like cloven hooves.
The Mercurys/Mirrors and the Doghan Daguis
Mercurys, beings that had transformed over time from primarily organic into mineral beings. Analytical, bordering on emotionless, they were almost more alien than the Kortân-Dahuks. Their more accessible “ambassadors,” the politically astute Doghan Daguis, were invaluable in smoothing out communications between humans and these beings also called the Mirrors.
The Palm Murets and the Arysum-Kormn
The Palm Murets followed, gaseous beings encased in soft metallic
exosuits and wearing elaborate, intimidating masks that belied their
inherently peaceful nature. So, too, did the stars behold the arrival
of the Arysum-Kormn, a nomadic race of explorers and travelers who
prided themselves on familiarity with every species in the galaxy.
The KCO2s and the Martapuraïs
The KCO2s, beings who fed on the negative emotions of others, were received with mixed emotions. While they needed to be near beings who suffered fear, pain, or despair, their feeding on such things, as Norton would famously say, “sure cleared the air for the rest of us.”
Martapuraïs arrived, introduced to the humans by their allies, the Kortân-Dahuks. They were aquatic beings encased in bulky full body suits that the captain who first met them, Ezekiel Trevor, likened to “old-fashioned deep-sea diving suits,” which permitted them to live outside of their watery environment. They were large, benevolent, and ichthyoid with long, tentacular arms. Their round-eyed heads were set in the center of their chests.
