The Talwin Trilogy

The Merseians discovered a star with an inhabited planet and named them Siekh and Talwin respectively after two heroes of their pre-Roidhunate Civil Wars. (Similarly, Cynthians named a planet and a city Llynathawr and Catawrayannis respectively before selling them to the Terran Empire.)

I could have made more links between Flandry's three trips to Talwin and between them and Aycharaych.

In A Circus of Hells

After Flandry has escaped from Talwin with Ydwyr as his prisoner, Ydwyr mentions Aycharaych but Flandry is too inexperienced to follow up on this lead. Thanks to both Flandry and Ydwyr, a joint Terran-Merseian scientific base is established on Talwin. Later, Uldwyr tells Desai:

"'You've made a good thing for your Naval Intelligence out of the joint commission on Talwin.' Desai, who knew that, kept silence."

-The Day Of Their Return, 3, p. 84.

In The Day Of Their Return

Desai reads that Flandry was temporarily assigned to the research base on Talwin because:

"...his special knowledge might conceivably help in gathering militarily useful data." (9, p. 144)

Thus, he spotted an unknown xenosophont, pumped a Merseian and learned something about Chereion although not as yet specifically about Aycharaych.

In A Knight of Ghosts And Shadows

The base on Talwin has become a convenient venue for discrete inter-imperial negotiations. During the Terran civil war, Tachwyr invites Molitor-supporter Flandry, hoping that the concealed Aycharaych will be able to read the Terran's mind. However, Flandry, onto Tachwyr's tricks, is protected by a mind-screen hidden under a Ramanujan turban. Calling Aycharaych out, Flandry has a memorable night-long conversation with him.

And that is Talwin's contribution to the Technic History. Quite a lot.