Slide the sail-area control to watch a model of JAXA's real IKAROS solar sail catch sunlight, and read how its measured photon-pressure thrust scales with sail size.
Only the 1.00x setting on the slider shows JAXA's real measured thrust figure - other settings scale the thrust in direct proportion to sail area, a genuine physics relationship, but never a separately published measurement. Drag to orbit and scroll or pinch to zoom on the scene above.
For a spacecraft that reaches its target using propellant and a rocket-equation delta-v budget instead of sunlight pressure, see the Tsiolkovsky Rocket Equation 3D Explorer. For a real mission that used propellant-based ion thrusters for its cruise, see the Psyche Metal Asteroid 3D Explorer.
Solar Sail Propulsion 3D Explorer - IKAROS
This browser explorer models JAXA's real IKAROS spacecraft, the world's first mission to successfully demonstrate solar-sail propulsion in interplanetary space - pushed forward by sunlight alone, with no propellant.
IKAROS launched 2010-05-21 (JST) on an H-IIA rocket from Tanegashima Space Center, alongside the Akatsuki Venus Climate Orbiter. Its square sail membrane measures about 14 m by 14 m (about 196 sq m), cut from polyimide film only 7.5 micrometers thick with an aluminum-vapor-deposited reflective coating; the membrane itself weighs about 2 kg, and 4 tip masses of about 0.5 kg each help deploy and tension it by spinning the spacecraft at roughly 1-2 rpm, with no rigid booms. Thin-film solar cells are attached to the same membrane, so it both catches sunlight for propulsion and generates electricity - JAXA calls this dual role a "hybrid" solar power sail. On 2010-07-09, JAXA confirmed via Doppler radar tracking that solar radiation pressure was producing about 1.12 millinewtons of thrust on the sail, matching the expected value and, per JAXA, the largest acceleration produced by photon pressure in the history of interplanetary flight at the time. Eight liquid-crystal reflectivity-control panels mounted on the sail's edges let IKAROS change its attitude using sunlight pressure alone; a JAXA test on 2010-07-23 achieved about 90 to 94 percent of the expected attitude-control performance. The spacecraft body is a cylinder about 1.58 m across and 0.95 m tall, with a total wet mass of about 307 kg at launch. These figures come from JAXA's mission press releases and overview pages, eoPortal's IKAROS satellite-mission page, and the peer-reviewed mission summary "Achievement of IKAROS" (Acta Astronautica, 2013), cross-referenced with an arXiv instrument paper for the spacecraft's body dimensions.
- Sail-area slider (0.25x to 2.00x) resizes a procedural square sail and scales the displayed thrust in direct proportion to area
- Only the 1.00x setting shows JAXA's real measured thrust figure - other settings are a proportional illustration, disclosed as such
- A facts panel and comparison table show the real sail size, mass, spacecraft mass, measured thrust, and attitude-control method
- A blue thrust-vector arrow points away from the Sun, showing the direction solar radiation pressure pushes the sail
- Small blue patches on the sail stand for the real thin-film solar cells attached to the membrane
- The sail spins slowly about the direction it faces the Sun, standing in for the real spin-stabilized deployment (sped up for visibility)
- Drag to orbit, scroll or pinch to zoom
- Runs fully in the browser with the vendored three.js engine - no account, no upload
| Real IKAROS figure | Value |
|---|---|
| Sail size | about 14 m x 14 m (196 sq m), 7.5-micrometer polyimide film |
| Sail membrane mass | about 2 kg (plus 4 tip masses, about 0.5 kg each) |
| Spacecraft mass | about 307 kg at launch (body about 1.58 m dia x 0.95 m tall) |
| Measured thrust (2010-07-09) | about 1.12 mN, confirmed via Doppler radar tracking |
| Attitude control | 8 liquid-crystal reflectivity panels, no propellant |
For a spacecraft that reaches its target using propellant and a rocket-equation delta-v budget instead of sunlight pressure, see the Tsiolkovsky Rocket Equation 3D Explorer. For a real mission that used propellant-based ion thrusters for its cruise, see the Psyche Metal Asteroid 3D Explorer.
Everything renders on your device with WebGL. The 3D engine loads once (about 0.7 MB) and is cached.
This is an educational approximation - the sail, tether, and thrust-arrow geometry are procedural, not a shape-accurate reconstruction or a solved radiation-pressure simulation, and only the 1.00x slider setting reflects a real published measurement. Every figure named above is real and independently published by JAXA, eoPortal, and the peer-reviewed mission summary cited above.
Frequently Asked Questions
What is IKAROS and when did it launch?
IKAROS is JAXA's Small Solar Power Sail Demonstrator, launched 2010-05-21 (JST) on an H-IIA rocket from Tanegashima Space Center alongside the Akatsuki Venus Climate Orbiter. It was the world's first spacecraft to successfully demonstrate solar-sail propulsion in interplanetary space.
How big is the real IKAROS sail, and what is it made of?
The square membrane measures about 14 m by 14 m (about 196 sq m), cut from polyimide film only 7.5 micrometers thick with an aluminum-vapor-deposited reflective coating. The membrane itself weighs about 2 kg.
How much real thrust did JAXA measure?
On 2010-07-09, JAXA confirmed via Doppler radar tracking that solar radiation pressure was producing about 1.12 millinewtons of thrust - matching the expected value and, per JAXA, the largest acceleration produced by photon pressure in the history of interplanetary flight at the time.
Why is IKAROS called a "hybrid" solar power sail?
Thin-film solar cells are attached to the same membrane that catches sunlight for propulsion, so the sail both pushes the spacecraft forward and generates electricity at the same time.
How does IKAROS steer without using propellant?
Eight liquid-crystal reflectivity-control panels mounted on the sail's edges change how much sunlight each part of the sail reflects, creating a steering torque from sunlight pressure alone. A JAXA test on 2010-07-23 achieved about 90 to 94 percent of the expected attitude-control performance.
What does the sail-area slider on this page actually change?
It resizes the sail model and scales the shown thrust value in direct proportion to sail area - a genuine physics relationship - but only the 1.00x setting displays JAXA's real measured thrust figure. Other settings are a proportional illustration, not separately published measurements.
How is this different from a rocket-equation or ion-thruster explorer?
The Tsiolkovsky Rocket Equation explorer covers propellant-based chemical or ion propulsion and its delta-v budget; the Psyche Metal Asteroid explorer covers a real ion-thruster cruise mission. This page is specifically propellant-free propulsion from sunlight pressure alone.
Where do these figures come from?
JAXA's mission press releases and overview pages, eoPortal's IKAROS satellite-mission page, and the peer-reviewed mission summary "Achievement of IKAROS" (Acta Astronautica, 2013), cross-referenced with an arXiv instrument paper for the spacecraft's body dimensions.