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Science Nexus

Megastructure · 5 stages
Science Nexus

Science Nexus is a megastructure in Stellaris 4.5.2 built in 5 stages. Each empire can only build one Megastructure. It needs the Science Nexus technology. All stages take 12620 days and 20,000 Unity (the costs every empire pays). The Groik Nexus produces 350 Society Research, 350 Engineering Research and 350 Physics Research a month.

Stages
5
Build time
12620 days
Unity
20,000
ID
think_tank_0

Where to build a Science Nexus

The game's own requirement line, then the conditions of the first stage (possible) and of the planet or star it goes around (placement_rules).

Each empire can only build one Megastructure.

The planet or star
  • Cannot build on an unsurveyed or habitable planet.
  • Cannot build on planets that have unresearched anomalies discovered by us or any other Empire.
  • Cannot build on a minor planetary body (asteroid or moon).
  • Cannot build around a star.
  • Cannot build around an astral scar.
  • Cannot build on Ring Worlds.
  • Cannot build due to existing Megastructure.
The system and the empire
  • The system has a starbase
  • Cannot build outside Empire borders.
  • Cannot build due to existing Megastructure.
  • Cannot build in systems that have not been surveyed.
  • Cannot build more than one Science Nexus.
  • Cannot build more than two Science Nexuses.

Science Nexus stages

Cost lines with a condition apply only to the empires it names (bio-ship empires pay food instead of part of the alloys).

How it's counted

Totals in the head count only the costs every empire pays: 20,000 Unity.

Stage 1

Science Nexus Site

This initial site will serve as the base for the future construction of a Science Nexus.

Build time
1,800 days
Cost
5,000Unity
5,000Alloys — if Not: Uses bio-ships
2,500Alloys — if Uses bio-ships
8,750Food — if Uses bio-ships
Upkeep / month
5Energy Credits
Produces / month
—
Stage 2

Science Nexus Hub

Equipped with a state of the art singularity reactor, the central core will cover most of the Nexus' energy needs. It will also connect the future research facilities.

Build time
3,600 days
Cost
5,000Unity
15,000Alloys — if Not: Uses bio-ships
7,500Alloys — if Uses bio-ships
26,250Food — if Uses bio-ships
Upkeep / month
25Energy Credits
Produces / month
100Society Research100Engineering Research100Physics Research
  • +5%All Technology Research Speed
Stage 3

Science Nexus Research Wings

The research wings will contain most of the labs and provide housing for the scientists. They come with multiple security chambers to allow for complete lockdown of various areas, if necessary.

Build time
3,600 days
Cost
5,000Unity
15,000Alloys — if Not: Uses bio-ships
7,500Alloys — if Uses bio-ships
26,250Food — if Uses bio-ships
Upkeep / month
50Energy Credits
Produces / month
200Society Research200Engineering Research200Physics Research
  • +10%All Technology Research Speed
Stage 4

Science Nexus

A fully equipped and operational Science Nexus.

Build time
3,600 days
Cost
5,000Unity
15,000Alloys — if Not: Uses bio-ships
7,500Alloys — if Uses bio-ships
26,250Food — if Uses bio-ships
Upkeep / month
75Energy Credits
Produces / month
300Society Research300Engineering Research300Physics Research
  • +15%All Technology Research Speed
Stage 5

The Groik Nexus

Named after its inventor, this Science Nexus has a neural bank containing the brain of one of our finest researchers integrated into its main drive, allowing it to operate at an increased speed.

Build time
20 days
Cost
—
Upkeep / month
100Energy Credits
Produces / month
350Society Research350Engineering Research350Physics Research
  • +15%All Technology Research Speed

How to unlock the Science Nexus

Science NexusTier 5 · 24,000

Other versions of the Science Nexus

Ruins the galaxy can start with or a war leaves behind (restoring one is its own chain of stages) and upgrades that branch off the main line.

Ruined Science Nexus (permanently ruined)

Stage 1

Ruined Science Nexus

This ruined Science Nexus is little more than an empty hulk. Its main hull has been damaged beyond repair.

Build time
—
Cost
—
Upkeep / month
—
Produces / month
—

Ruined Science Nexus (ruined)

Stage 1

Ruined Science Nexus

A ruined Science Nexus. Although its insides were stripped clean by looters eons ago, the megastructure's main hull is still mostly intact. With the right technology and a lot of resources, it could potentially be refurbished.

Build time
—
Cost
—
Upkeep / month
—
Produces / month
—
Stage 2

Science Nexus

A fully equipped and operational Science Nexus.

Build time
4,800 days
Cost
3,200Unity
15,000Alloys — if Not: Uses bio-ships
7,500Alloys — if Uses bio-ships
26,250Food — if Uses bio-ships
Upkeep / month
75Energy Credits
Produces / month
300Society Research300Engineering Research300Physics Research
  • +15%All Technology Research Speed

Science Nexus: questions

Where can I build a Science Nexus?

Each empire can only build one Megastructure. Cannot build on an unsurveyed or habitable planet. Cannot build on planets that have unresearched anomalies discovered by us or any other Empire. Cannot build on a minor planetary body (asteroid or moon). Cannot build around a star. Cannot build around an astral scar. Cannot build on Ring Worlds. Cannot build due to existing Megastructure.

How do I unlock the Science Nexus?

Research Science Nexus.

How long does a Science Nexus take to build?

12620 days for all 5 stages (Science Nexus Site: 1800 days, Science Nexus Hub: 3600 days, Science Nexus Research Wings: 3600 days, Science Nexus: 3600 days, The Groik Nexus: 20 days), before build-speed modifiers.

Source: common/megastructures/03_think_tank.txt and localisation/english, Stellaris Cygnus v4.5.2 (9776). Build times before build-speed modifiers.

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