The TITANs were active across the solar system, including the Jupiter system. The Carpo installation (destroyed with antimatter charges 1 AF), the devastating outbreaks on Zeus Station and the Adrastea mining platforms, as well as the mysterious fate of the Synnott base on Io provide ample evidence. Still, compared to the devastation on Earth, Luna and Mars and the megaengineering at Iapetus the Jupiter system seems almost suspiciously free of TITAN artefacts. This is of course wrong: the TITANs were quite busy at the largest mass concentration outside the sun; it was just that most of their activities were hidden from transhumanity.
One of the artefacts constructed by the TITANs was a floating factory in the Jovian atmosphere. It might not be the only one (even though it is enormous, it is dwarfed by the giant planet and hidden under clouds and electric discharges) but this is the only one discovered by transhumans. It is a treasure, trap and threat all in one.
During their rapid evolution the TITANs at one point were considering seeding the solar system with self-replicating technology and turn it into a Matrioshka brain. Before long they advanced beyond that stage and began to explore more advanced femtotech, the gates and other incomprehensible technologies. But some early systems remained. The factory is one such early transcendent artefact: amazingly powerful, but still merely ultra-advanced nanotechnology and superintelligence rather than something truly alien.
The installation was discovered by gas miners from Owen Deuterium Solutions a few years. Knowing what was best for them, they quietly and urgently informed the Jovian Republic navy. The navy immediately moved in to maintain total security and secrecy, setting up project “Indigo Longitude”. The aims were 1) to prevent any danger from the installation, 2) keep other groups from discovering it, and 3) to investigate it.
Indigo Longitude is now run under the double cover of a Jovian Republic Naval Research Agency-run gas mining and energy production experiment codenamed Cloudy Trombone. Cloudy Trombone operates a “secret” floating gas mining aerostat, Jovanovich, hovering in the upper Jovian atmosphere, apparently experimenting with deep atmosphere tethers. Owen Deuterium Solutions was bought by the Republic and is operating Jovanovich. The work at the aerostat is real and of some military relevance to the navy, so the cover is not too implausible. That engineers, scientists and other personnel is shipped down to the aerostat under great secrecy looks just like typical military paranoia. In reality they are then shipped further down using the tether to Indigo Latitude, where the real work takes place.