Astrophysics

Unlike most other technology research, Astrophysics serves multiple distinct purposes:

Each odd level (1, 3, 5, 7, …) allows an additional colony planet.¹⁾
Each square level (1, 4, 9, 16, …) enables an additional simultaneous expedition.
Each level allows expeditions to remain on mission for an additional hour.²⁾
Certain levels allow colonization of planets closer to the inner and outer edges of a solar system.

Astrophysics level 1 must be researched before any planets can be colonized beyond the starting Main Planet.

Colony ships may be sent on colonization missions even when lacking requisite Astrophysics level for additional colonies.
However, they will be forced to return to their origin if the appropriate Astrophysics level is not met by the time they reach their destination.

Planet positions

At certain Astrophysics levels, it becomes possible to colonize planets closer to the inner and outer edges of a solar system.

Level	Colonizable positions
1	4 - 12
4	3 - 13
6	2 - 14
8	1 - 15

Number of expeditions

At certain Astrophysics levels, it becomes possible to conduct more expeditions simultaneously.

Level	Simultaneous expeditions
0	0
1	1
4	2
9	3
16	4
25	5

Construction Costs

Resource	Construction Costs
Resource	Level X	Total costs up to Level X (from Level 0)
Metal	100 * ROUND DOWN ( 0.5 + 40 * ( 1.75 ^(X-1) ) )	16,000 / 3 * ( 1.75 ^(X-1) )
Crystal	100 * ROUND DOWN ( 0.5 + 80 * ( 1.75 ^(X-1) ) )	32,000 / 3 * ( 1.75 ^(X-1) )
Deuterium	100 * ROUND DOWN ( 0.5 + 40 * ( 1.75 ^(X-1) ) )	16,000 / 3 * ( 1.75 ^(X-1) )

¹⁾

Since only every second level enables a new colony, it usually makes sense to research two levels at a time.

²⁾

Additional time beyond the minimum does not affect the outcome of the mission.