Space Datacenter Interactive Explorer

Inputs

How to use this explorer

Keep the default settings for a clean baseline, then move one slider at a time. Watch how Space Premium, effective launch $/kg, and satellite mass respond.

Three things to try first: (1) Change Compute module preset to Vera Rubin Space-1 to see how a higher-TDP chip shifts the fleet cost. (2) Drag Altitude from 550 km to 7,000 km to see the launch penalty climb. (3) Halve the Base launch cost (Starship scenario) to see how dominant launch economics are.

Use the i icons beside each parameter for plain-language definitions and source references.

Datacenter size to replace MW

How much terrestrial compute capacity to match. Larger values scale the whole fleet proportionally — the Space Premium grows linearly here.

Orbital altitude km

Higher orbits cost exponentially more to reach via the Hohmann transfer penalty. LEO (~550 km) is cheapest; MEO (~7,000 km) is the notebook baseline; GEO (~35,786 km) is extremely expensive to reach.

Key sensitivity knobs

These are the parameters with the biggest effect on the Space Premium. Anchor values come from the notebook references; the cards below each group show the specific numbers.

Compute module preset

Sets the GPU chip generation: rack power (kW), module mass (kg), and cost anchor ($/kW). The anchor cards below update to match the selected chip.

Launch cost preset Base launch cost (to baseline altitude) $/kg Transfer Isp s

Specific impulse of the kick stage used to raise orbit above the baseline altitude. Higher Isp = less propellant mass needed = lower altitude penalty.

Propulsion dry-mass fraction %

Kick-stage hardware mass as a share of propellant mass. The hardware also has to be launched, so a higher fraction makes altitude changes more expensive.

Launch model: baseline $/kg to , then a notebook-style Hohmann transfer mass multiplier above that altitude.

Sources:

Solar array specific power W/kg

How many watts of solar power each kilogram of array delivers. Higher values mean lighter arrays, which cuts both array mass and launch cost. Solar arrays are the largest mass driver at high altitudes.

Radiator emissivity

How efficiently the radiator surface radiates heat to space (1.0 = perfect blackbody). Higher emissivity means more heat rejection per m², so smaller and lighter radiators.

Radiator areal density kg/m²

Mass per square meter of radiator panel. A heavier radiator per m² directly increases satellite mass and launch cost, since more area is needed to reject the full compute heat load.

Advanced settings (thermal, orbital geometry)

These settings affect the thermal sizing model and orbital sunlight geometry. They have smaller effects than launch cost and altitude for most scenarios, but matter at the margins — particularly GPU temperature for radiator sizing.

GPU junction temperature °C

Operating temperature of the GPU heat source. The radiator must stay cooler than this (minus the transport delta T below). Higher values allow a warmer — and therefore more efficient — radiator, reducing required area.

Transport temperature drop (ΔT) °C

Temperature budget lost between the GPU and the radiator surface (heat pipes, pumped loops, interface resistances). A larger ΔT forces a cooler radiator, which needs more area to reject the same heat.

Non-compute power overhead %

Extra electrical load beyond the GPU compute modules — power conversion losses, coolant pumps, control electronics, and support systems. Raises total satellite power draw and therefore solar array size.

Constellation beta mix preset

Beta angle is the angle between the orbital plane and the sun direction. Higher beta = more time in sunlight. This preset controls the assumed distribution of beta angles across the constellation.

Beta mix visual editor

Results Live

All figures update live. The Space Premium (highlighted) is the headline — it measures how much more expensive a space-based GPU fleet is compared to buying the same GPU hardware for a ground datacenter.

Space Premium

Extra CAPEX above GPU hardware cost — the price of orbit: launch + arrays + radiators + bus structure.

Fleet CAPEX

Total cost of all satellites: GPU hardware + every space-specific cost.

GPU Hardware Cost

What the equivalent compute would cost to buy outright for a terrestrial datacenter. Space Premium = Fleet CAPEX − this number.

Effective Launch Cost

$/kg delivered to the target altitude, after applying the Hohmann transfer mass multiplier for orbits above the baseline altitude.

Weighted Satellite Mass

Beta-angle-weighted average mass per satellite. Includes compute module, radiators, solar arrays, and bus structure.

Satellites Needed

Fleet size required to deliver the target compute continuously, scaled up to compensate for eclipse downtime.

Fleet CAPEX Split

GPU hardware cost vs. the Space Premium (everything else). A thin GPU bar and tall Space Premium bar means orbit is adding a large multiple on top of the hardware price.

Space Premium vs Datacenter MW

How the Space Premium scales with the datacenter size you want to replace. The dot marks your current selection. In this model the premium scales linearly — no economies of scale from building a larger space fleet.

Space Premium Cost Build-Up

Waterfall showing the four space-specific cost categories that add up to the Space Premium. Hover each bar to see the dollar value. Launch typically dominates at high altitudes; solar arrays are the main mass driver.

Launch Cost Drivers by Mass

How launch spend breaks down by which component is being lifted. Lighter solar arrays (higher W/kg) or radiators (lower kg/m²) directly cut the launch bill proportionally.

Constellation Visualizer

Illustrative 2D perspective sketch of the fleet at the selected altitude. Satellites are grouped by beta-angle family (color-coded). This is for visual intuition only — orbits are not propagated mechanically.

Source Footnotes

Tooltip footnotes and anchor cards point here so users can trace major mass, solar, launch, and assumption anchors back to notebook-linked references.

Interactive Space Premium Explorer

Results Live

Fleet CAPEX Split

Space Premium vs Datacenter MW

Space Premium Cost Build-Up

Launch Cost Drivers by Mass

Constellation Visualizer

What This Tool Models

Notebook Reference Snapshot

Reference Inputs

Reference Outputs

Current Delta vs Reference

Source Footnotes