T+0 · Stage 1 raise

A laser rail to the stars, built one satellite at a time.

Fuel-less sail probes, pushed outward by a chain of solar-powered laser stations instead of one giant laser. Stations go up a few per launch and are dropped off outward from the Sun. Each rung of the build produces flight data.

$25M for Stage 1: four sets of flight data, the first laser push of a sail in space, and the first station-to-station handoff.

Stage 1$25M4 years3 launches

01 / The problem

Sixty years of proposals. The same wall every time.

Physics

Laser sails have been proposed since the 1960s. The physics has been accepted since Forward's 1984 paper. Nobody disputes the equations.

Scale

Every design since has asked for one enormous laser or lens. Hundreds of kilometres of optics, gigawatts on day one.

Money

Every attempt died on the same two things: scale and the cheque that had to be written before any data existed.

02 / The concept

The rail.

Instead of one laser holding focus across light-years, a chain of stations passes the probe along. Power stations sit near Mercury's orbit, at roughly 0.3 AU, where sunlight is about seven times stronger than at Earth. Relay stations along the outward track, big but light, hundreds of metres across and a few tonnes each, keep the beam focused. A probe sails inward on sunlight, whips around the Sun, and is pushed out from behind. The same sail does the braking and the flying: no propellant.

1 · Dive

The probe sails inward on sunlight, the same sail, no propellant. Leaving Earth it carries Earth's 30 km/s orbital speed and must shed about 17 km/s to drop its perihelion to 0.1 AU. A 1 kg probe with a 22 m sail feels sunlight at about three-quarters of the Sun's gravity, so it brakes against its orbit on sunlight alone. Projected: 2–4 months of sailing, then 74 days of fall.

2 · Whip

It rounds the Sun at 0.1 AU, close to the power stations, already moving fast. Projected: about 11 days inside 0.25 AU, up to 127 km/s. At 0.1 AU the sail runs at roughly 600–1,050 K (projection); silicon nitride melts above 1,900 K.

3 · Push

Stations behind it fire in turn along the outbound leg. Each keeps the probe close enough that its optics stay far smaller than one giant laser's. Projected: 8.5 hours on the rail to 10% of light speed.

Projection About six months from launch to the start of the 43-year cruise.

How it gets built.

Power stations · 3, heavy

Solar collectors and lasers near Mercury's orbit, about 0.3 AU, where sunlight is about 7× stronger. One dedicated heavy-lift launch each. Reaching Mercury's orbit is the hard part: MESSENGER and BepiColombo needed 6–7 years of planetary flybys. Ours can sail inward on their own collector membranes, or use Venus flybys.

Relay stations · ~27, big but light

Their size is set by geometry, not power. To hold the beam on a 22 m sail across a 0.1 AU gap, each needs a membrane optic about 700 m across. At a few grams per square metre that is 1–10 tonnes apiece Projection. A single carrier launched outward drops 4–10 of them as it goes. Each settles into its own orbit using its membrane as a solar sail.

The probe · 1 rideshare slot

Light enough to sail out of Earth orbit on sunlight. The cheapest launch in the program is the one that leaves for another star.

Projection About 30 stations. Roughly 10–15 launches. Not 30.

Why a rail, not a laser

A single laser has to hold focus over light-years. That needs a lens or aperture hundreds of kilometres wide. A chain keeps the probe near the last station that pushed it, so every station's optics stay far smaller than a single laser's would.

Why it can be built incrementally

Power stations get a heavy-lift launch each. Relay stations are big but light, hundreds of metres across and a few tonnes, and a single carrier drops several of them off outward from the Sun. The first rung is a lab bench. The second is one cubesat. Each rung produces data the next rung is priced on.

03 / Why now

Three things changed.

June 2026 · Delft 0.3 GW/m² Sail material survives Starshot-class intensity

A Delft team hit a 4 mm silicon-nitride sail with a 230 W laser at 0.3 GW/m² and measured about 100 g of acceleration. The sail material question is largely answered.

February 2026 · SpaceX rideshare $350k To orbit for up to 50 kg

Sun-synchronous orbit at $350k for up to 50 kg, and $7k per kilogram above that. Laser-communication pointing hardware is commodity. A Stage 1 rung is a smallsat, not a program.

Since ~2023 · Breakthrough Starshot On hold The field is open

The one funded laser-sail program has been on indefinite hold since about 2023, with most of its pledged $100M never delivered. No one is flying this.

Never done, in sixty years of proposals: a laser pushing a free-flying sail in space, and one station handing a sail to the next. The rail depends on both. Both are cheap.

04 / Physics in one line

Thrust on a reflective sail is 2P/c.

F = 2P/c
Twice the beam power over the speed of light
1 kW = 6.7 µN
One kilowatt of beam gives 6.7 micronewtons of thrust

It scales linearly. A kilowatt in orbit and a gigawatt on the rail obey the same line, so kilowatt flight data is direct evidence for a gigawatt rail, not an analogy.

05 / Stage 1

The ladder.

Four rungs, each with a numeric pass/fail metric, a cost band, and a timeline. Stage 1 is about $20–25M over roughly four years. First flight data arrives at about $3M.

Rung 0 · Lab

A sail under a 1 kW beam in vacuum.

Proves the sail survives the beam intensity and the force matches the equation.

Success metric
Survives ≥60 s at ≥0.1 GW/m². Reflectivity ≥95%. Measured force within 20% of prediction.
Cost
$0.2–1M
Timeline
6–12 months
Running total $0.2–1M
Rung 1 · Orbit

Pointing at range, no sail.

One 12U cubesat holds a 1–10 W laser on a released retroreflector out to about 100 km.

Success metric
On target ≥90% of a pass at 10 km, ≥50% at 100 km. Cold acquisition under 60 s.
Cost
$2–4M
Timeline
18–24 months
Running total $2.2–5M · first flight data at ~$3M
Rung 2 · Orbit

First laser push of a free-flying sail in space.

An ESPA-class smallsat with a 1 kW fibre laser fires 9-minute battery bursts in Earth's shadow at a 10 g sail-craft with a 30 cm sail. Each burst adds 0.36 m/s, measured by Doppler ranging.

Success metric
≥10 bursts within 30% of prediction. Sail reflectivity ≥90% afterward.
Cost
$8–12M
Timeline
2–3 years
Running total $10.2–17M
Rung 3 · Orbit

Handoff.

A second identical satellite 10–50 km away takes over the push. The first thing the rail needs that has never been done.

Success metric
Re-acquire within 60 s of cutoff. Cumulative Δv within 20% of the sum. ≥5 clean handoffs.
Cost
$6–9M
Timeline
+12–18 months
Running total $16.2–26M
~$20–25M
Stage 1, all four rungs, with program overhead
~4 years
Rung 0 through Rung 3
~$3M
First flight data, Rung 1 complete

Stage 1 is three launches: one rideshare slot each for Rungs 1, 2 and 3.

06 / The deliverable

What $25M buys.

Four sets of flight data

Bench, pointing, push, and handoff. Each with a numeric metric that was set before the money was spent.

The first laser push of a sail in space

A free-flying sail accelerated by a laser in orbit, measured by Doppler ranging. Not done in sixty years of proposals.

The first handoff

One station releases the sail and the next picks it up. This is the operation the whole rail is made of.

A fundable Stage 2

With the two never-done things done and the numbers in hand, the solar-powered megawatt station becomes an engineering estimate rather than a bet.

What it doesn't.

$25M does not build the rail, and it does not send a probe toward Alpha Centauri. It ends with a sail pushed by one satellite and handed to a second in low Earth orbit — the first two-station rail ever flown — plus the lab, pointing and thrust data. That is the evidence the next round needs.

$25M does not build the rail. It makes the rail fundable.

Cost ladder · order-of-magnitude projections

Stage 1$20–25M

Proof

Projection
Stage 2~$150–400M

One solar-powered MW station

Projection
Stage 3~$0.5–1.5B

Mercury-orbit station and sun-dive probe

Projection
Stage 4Tens of billions

The rail, dominated by laser cost per watt

Projection

Stage 1 is roughly 0.1% of the program and retires the two risks no one has tested in space.

07 / Beyond Stage 1

Where it leads.

Everything in this section is a projection. It is what the physics and the current cost of hardware allow, not a commitment.

Stage 2 · Projection

A solar-powered megawatt station.

The first heavy station: solar-powered, megawatt-class beam, placed inward from Earth. It proves the power-station design the rail is made of.

Stage 4 · Projection

The rail.

About 30 stations from 0.3 to 3 AU: solar power stations near Mercury's orbit and relay stations trailing outward, dropped off several per carrier launch.

Projection

A probe to Alpha Centauri.

0.1c
10% of light speed
8.5 h
time under beam
~150 GW
total beam power
~43 yr
to Alpha Centauri

A 1 kg probe with a 22 m sail at 100 g of acceleration, pushed by the full rail. Projected figures based on 2P/c and the Stage 4 station count.

For scale: Voyager 1 has been flying for 49 years and is 171 AU from the Sun, moving at 16.9 km/s. It is the most distant human-made object ever built. Distance as of September 2026.

Projection 1,780×

Coming off the rail at 30,000 km/s, the probe is travelling about 1,780 times faster than Voyager 1.

Projection ~10 days

It passes Voyager 1's current distance roughly ten days after the push ends.

08 / What we get

What we get.

Alpha Centauri.

The nearest star system, about 4.3 light-years away. Three stars: two Sun-like stars, A and B, orbiting each other, and Proxima Centauri, a red dwarf at 4.24 light-years, the nearest star of all. Proxima has a confirmed roughly Earth-mass planet in its habitable zone, Proxima b, on an 11-day orbit, and a smaller confirmed planet, Proxima d.

In August 2024 JWST imaged a candidate Saturn-to-Jupiter-mass planet about 2 AU from Alpha Centauri A. It is still unconfirmed and awaiting follow-up. Aug 2024 observation; 2025 analysis. Source.

It is the closest place with a possibly habitable world to look at.

What a 1 kg flyby at 10% of light speed returns.

The probe cannot stop. It crosses the Sun–Earth distance in 83 minutes, so the science at the target lasts hours.

Images of Proxima b

Tens to hundreds of km per pixel from a 10 cm camera, depending on approach distance. Any telescope gives a single pixel for the foreseeable future.

A close-range spectrum of its atmosphere

Water, oxygen, methane. The biosignature question.

A magnetometer reading

Whether the planet has a magnetic field, the make-or-break for habitability around a flaring red dwarf.

The star's wind and dust environment

Measured in place, at the star.

And for the entire cruise: the first sustained sampling of the interstellar medium beyond the Sun's bubble. Voyager only touched its edge.

Projection

Data comes home at bits to kilobits per second, using the sail itself as the antenna. The signal takes 4.2 years. First images arrive roughly 48 years after launch.

The same rail, closer to home.

Run at lower speed, the same rail delivers probes across the solar system in days.

Projection Neptune in ~17 days

At 1% of light speed.

Projection Pluto in ~23 days

At 1% of light speed. New Horizons took 9½ years.

Fast flyby probes to the outer planets and the interstellar boundary are the near-term product. Alpha Centauri is the proof that the rail reaches beyond the solar system at all.

09 / Risks we're not hiding

What could stop this.

Sail limits at gigawatt beams

Delft's result is at Starshot-class intensity on a 4 mm sample. Metre-scale sails under gigawatt beams are a lab problem that is progressing, not a solved one. Rung 0 is where we find out on our own hardware.

Power-station cost at Stage 4

The financing cliff. Stage 1 costs tens of millions; the full rail costs far more. Stage 1 data exists to make the next cheque fundable on evidence, not on a slide.

Orbital shear

Stations at different solar distances orbit at different rates. The rail is not a straight line; it is a network that lines up in launch windows. That is a scheduling constraint we design around, not a physics objection.

10 / Standing on prior work

The physics is forty years old. The build plan is not.

1984Forward

A solar laser near Mercury and a 1,000 km lens near Saturn. The physics has stood for forty years; the scale was judged absurd.

2012–13Bae · Photonic Railway

Stations in a line. NASA NIAC Phase I. Never funded past the bench.

2016Breakthrough Starshot

One 100 GW ground array. Funding never arrived.

2019van den Donker · JBIS

Solar-pumped stations firing in succession, 10 g probe to 7.7% of light speed.

What is new here is the incremental build, so that partial funding buys real flight data, and the sun-dive-then-push geometry.

11 / Team

Who is building it.

Mike Taylor

Founder

12 / Stage 1 · $25M

Partner with us.

We are raising $25M for Stage 1 from investors and philanthropic funders who want to see the first laser push of a sail in space, and the first handoff, measured and published. First flight data at about $3M.