- Ihikkk (Zeta Tucanae IV) - Text by M. Alan Kazlev
In Anglish, Snowwhite. A glacial world just outside the life zone, covered with massive ice sheets, terraformed to produce a glacial ecosystem rather than a temperate ecosystem.
- Incident - Text by M. Alan Kazlev
Important Metasoft system.
- Incorp - Text by M. Alan Kazlev and Steve Bowers
Important Metasoft colony, located on a large moon of a gas giant.
- Iota Persei - Text by Anders Sandberg
Minor star Iota Persei is surrounded by an asteroid belt that came to be inhabited by refugees, many from the nearby system of Bourgatov. This belt, colloquially known as The Iota evolved from a squatter camp The waning economy led to emigration, which in turn hastened the decay. The last (known) inhabitants left in 9300.
- Iota Virginis - Text by Alex Mulvey
System containing the Refractory, a megastructure artform.
- Irrmorella - Text by M. Alan Kazlev
Small Negentropist system about 16 ly from Greylag, famous for being the first port of call of the the Sentient Museum Ship Ken Ferjik.
- Ishtar's Necklace - Text by Liam Jones
Ancient xeno megastructure in the Carina Rush.
- Isi-IV - Text by M. Alan Kazlev
NoCoZo world, home to the famous Mayane collection, which features some important examples of Perfect Art.
- Ithiplumo (GJ 3379) - Text by Anders Sandberg
A carbonaceous planetoid orbiting the dim M3.5 star LTT 17897. Notable for the signs of ahuman manufacturing on the surface, dated in the 4th century AT.
- Ivonya-Ngia - Text by Steve Bowers
Former Elephant colony in Aquila. Now a cosmopolitan world with many clades.
- Ixeway (HIP 94595) - Text by Anders Sandberg
MPA system; M-type star near Ascella, the site of the original Argus Array.
- Jafalgia - Text by James Rogers
Metasoft reserve planet. Jafalgia has a long history of baseline artists, writers and musicians (such as Haliki Movarion and others), some of whom attempt to ascend to posthuman status, never to be heard from again. Jafalgia is also the world where the enigmatic transapient performance artist Quizical first appeared.
- Jarre - Text by Extherian, from an original article by Tapio Erola
A former Lo-Tech colony at the edge of the Perseus Arm, disrupted by badly-managed contact with outsiders
- Jedman II - Text by M. Alan Kazlev
Outer Volumes Sagittarius Transcultural Cooperation planet, recently visited by the Caretaker-derived artefact known as the Guidestar as a mark of exemplary environmental maintenance by the inhabitants. The planet is famous for its dramatic scenery.
- Jekaumeatrine - Text by M. Alan Kazlev
Brown Dwarf in the Centaurus region, used as neutral ground for the negotiations at the end of the Paradigm War. Currently the local HQ of the Paradigm Containment Organisation.
- Jensan - Text by M. Alan Kazlev
Sophic League world, one of the centers of the Artists of Gleia
- Jesanu - Text by M. Alan Kazlev
The planetary archai on this world reconfigures actual events for visitors into Free-form Perfect Art
- Jewel Box, The - Text by M. Alan Kazlev
NGC 4755 (also known as Kappa Crucis); an open cluster of about 100 stars, past the Crucis Outer Periphery. This very young cluster is less than 10 million years old and is about 7500 light-years from Sol. A number of relativistic ai expeditions have been launched over the centuries, but the first is not expected to arrive for another 1800 years
- Jhairrn - Text by M. Alan Kazlev
Home world of the Harrroh race of sufants.
- Jilunan (system) - Text by M. Alan Kazlev
Novelty world and narcissist pilgrimage spot, known for the famous Fubas Clone Goo Disaster.
- Jinvanco (Struve 2398) - Text by MacGregor
Inner Sphere Binary Red Dwarf System
- Jirayaka (Garden World) - Text by The Astronomer, dangerous_safety
Life-bearing water world with partially frozen seafloor
- Jje-34 - Text by M. Alan Kazlev
Location of the Greater Hemisphere, an important example of a transingularity Perfect Art accessible to subsingularity beings
- Joden - Text by M. Alan Kazlev
Santana Habitat was the birthplace of Stig Ranes
- Jordana - Text by M. Alan Kazlev
It is thought that the MPA philosopher and fabulist Quistan Kemshola was killed in a shuttle crash on Jordana in 4694.
- Junna - Text by M. Alan Kazlev
Minor Negentropy Alliance world. During the period from 3267 to 3421 was center for the Institute of Baseline Psychotypology. Suffered during the Version War and became an MPA garrison. Since the age of separative empires the locals have drifted increasingly towards Zoeticism
- Jupkai - Text by Aaron Hamilton
The former homeworld of the extinct Iahi Daon species.
Text by Orion's Arm Editors
Initially published on 31 December 2007.