Mission path
An edited tour of a candidate simulation. Mission time skips between chapters.
Loading the simulation.
Technical details
Readout
- Mission elapsed
- 0 d 00:00
- Lunar altitude
- n/a
- Earth apparent size
- 152.7 deg
- Line of sight to Earth
- Clear
On the map, distances are to scale and bodies are drawn larger so they are visible at all. The camera view is true scale.
Simulated candidate trajectory. Not a flight design. No launch date exists. Case design-c-v1. Trans-lunar injection 2030-07-27, first lunar flyby at 6,499 km on the far side. Generated on 2026-09-23 from run a0a5d9a. Spacecraft pointing is a visual convention, not attitude dynamics.
The story as text
Leaving home
The spacecraft leaves a 185 km parking orbit and heads for the Moon. Earth shrinks behind it.
Parking orbit: 185 km. Injection burn: 3,140 m/s. From Earth after a day: 202,257 km.
Earthrise
After 4 days the spacecraft passes behind the Moon. As it comes round, Earth rises over the lunar horizon: the photograph the mission is designed around.
Closest approach: 6,499 km. Earth across: 1.836 deg. Window: 402 s.
Sending the photos home
The path loops back towards Earth. Goonhilly Earth Station has the spacecraft in view for 9.6 hours, a chance to send the Earthrise frames home.
Station in view: 9.6 hours. Highest elevation: 36 deg. From Earth: 94,576 km.
Looking back at Earth
After the last close return the spacecraft climbs away, and the whole of Earth fits in one frame.
From Earth: 120,905 km. Earth across: 6.048 deg. Earth lit: 87 per cent.
Second lunar pass
A second lunar pass, closer than the first, gives the spacecraft the energy to leave. There is no Earthrise here; Goonhilly Earth Station has it in view for a second downlink.
Altitude: 818 km. Mission day: 31. Station in view: 11.5 hours.
Leaving for the Solar System
The spacecraft leaves the Earth-Moon system. Further out, Earth and the Moon fit in one frame.
From Earth: 2.23 M km. Earth lit: 26 per cent. Moon lit: 26 per cent.
Events
| When | Event | Show on the viewer |
|---|---|---|
| Day 0, 0 minutes | Trans-lunar injection3140 m/s from a 185 km parking orbit | |
| Day 2, 0 hours | First-pass correction0.0 m/s impulse | |
| Day 4, 10 hours | Earth occulted by the Moon20.3 minutes without a line of sight | |
| Day 4, 11 hours | Earthrise: Earth clears the limb402 s of Earth's disc across the sunlit limb, crossing at 0.0046 deg/s; one frame every 40.2 s gives ten across the event | |
| Day 4, 11 hours | Earth reacquired | |
| Day 4, 11 hours | Clear-limb window opens456 s of Earth clear above the illuminated limb | |
| Day 4, 11 hours | Lunar closest approach6,499 km altitude, far side, 1.42 km/s relative | |
| Day 4, 11 hours | Clear-limb window closes | |
| Day 5, 11 hours | Loop targeting0.0 m/s impulse | |
| Day 7, 7 hours | Whole Earth windowEarth 6.0 deg across at 120,987 km, 94 per cent lit, whole disc at 50 mm, 0.60 to 0.90 of the frame height, for 6.2 hours | |
| Day 7, 13 hours | Earth detail window (cropped)Earth 10.2 deg across at 71,903 km, 88 per cent lit, cropped disc at 50 mm, 0.90 to 2.00 of the frame height, for 5.0 hours | |
| Day 7, 16 hours | Whole Earth windowEarth 12.1 deg across at 60,442 km, 86 per cent lit, whole disc at 25 mm, 0.60 to 0.90 of the frame height, for 2.1 hours | |
| Day 7, 18 hours | Earth detail window (cropped)Earth 22.0 deg across at 33,399 km, 72 per cent lit, cropped disc at 25 mm, 1.00 to 1.99 of the frame height, for 1.5 hours | |
| Day 7, 21 hours | Return perigee 19,874 km from centre, 3,496 km altitude | |
| Day 7, 22 hours | Earth detail window (cropped)Earth 22.0 deg across at 33,491 km, 72 per cent lit, cropped disc at 25 mm, 1.98 to 1.00 of the frame height, for 1.5 hours | |
| Day 7, 23 hours | Earth detail window (cropped)Earth 10.2 deg across at 71,968 km, 88 per cent lit, cropped disc at 50 mm, 1.99 to 0.90 of the frame height, for 5.0 hours | |
| Day 8, 0 hours | Whole Earth windowEarth 12.1 deg across at 60,698 km, 85 per cent lit, whole disc at 25 mm, 0.90 to 0.60 of the frame height, for 2.1 hours | |
| Day 8, 4 hours | Whole Earth windowEarth 6.0 deg across at 121,025 km, 93 per cent lit, whole disc at 50 mm, 0.90 to 0.60 of the frame height, for 6.2 hours | |
| Day 16, 12 hours | Family portrait windowEarth and Moon in one 200 mm frame for 0.3 days, 2.82 to 1.00 deg apart; Earth 100 per cent lit (full), Moon 99 per cent lit (full) | |
| Day 17, 4 hours | Family portrait windowEarth and Moon in one 200 mm frame for 0.3 days, 1.00 to 2.77 deg apart; Earth 100 per cent lit (full), Moon 100 per cent lit (full) | |
| Day 21, 5 hours | Whole Earth windowEarth 6.0 deg across at 120,983 km, 98 per cent lit, whole disc at 50 mm, 0.60 to 0.90 of the frame height, for 6.2 hours | |
| Day 21, 11 hours | Earth detail window (cropped)Earth 10.2 deg across at 72,009 km, 95 per cent lit, cropped disc at 50 mm, 0.90 to 2.00 of the frame height, for 5.0 hours | |
| Day 21, 13 hours | Whole Earth windowEarth 12.1 deg across at 60,522 km, 93 per cent lit, whole disc at 25 mm, 0.60 to 0.90 of the frame height, for 2.1 hours | |
| Day 21, 16 hours | Earth detail window (cropped)Earth 22.1 deg across at 33,334 km, 83 per cent lit, cropped disc at 25 mm, 1.00 to 1.98 of the frame height, for 1.4 hours | |
| Day 21, 18 hours | Return perigee 29,455 km from centre, 3,077 km altitude | |
| Day 21, 20 hours | Earth detail window (cropped)Earth 21.4 deg across at 34,340 km, 63 per cent lit, cropped disc at 25 mm, 1.86 to 1.00 of the frame height, for 1.4 hours | |
| Day 21, 21 hours | Earth detail window (cropped)Earth 10.2 deg across at 72,084 km, 80 per cent lit, cropped disc at 50 mm, 1.99 to 0.90 of the frame height, for 5.0 hours | |
| Day 21, 21 hours | Whole Earth windowEarth 12.1 deg across at 60,604 km, 77 per cent lit, whole disc at 25 mm, 0.90 to 0.60 of the frame height, for 2.1 hours | |
| Day 22, 2 hours | Whole Earth windowEarth 6.0 deg across at 120,905 km, 87 per cent lit, whole disc at 50 mm, 0.90 to 0.60 of the frame height, for 6.2 hours | |
| Day 24, 12 hours | Second-pass targeting0.0 m/s impulse | |
| Day 30, 12 hours | Final approach0.0 m/s impulse | |
| Day 31, 12 hours | Lunar pass 22,555 km from centre, 818 km altitude | |
| Day 32, 5 hours | DepartureGeocentric specific orbital energy crosses zero | |
| Day 55, 13 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.9 days, 3.52 to 3.55 deg apart; Earth 26 per cent lit (crescent), Moon 26 per cent lit (crescent): two crescents | |
| Day 68, 21 hours | Family portrait windowEarth and Moon in one 200 mm frame for 1.6 days, 3.59 to 1.00 deg apart; Earth 30 per cent lit (crescent), Moon 28 per cent lit (crescent): two crescents | |
| Day 71, 9 hours | Family portrait windowEarth and Moon in one 200 mm frame for 1.9 days, 1.00 to 3.60 deg apart; Earth 31 per cent lit (crescent), Moon 33 per cent lit (crescent): two crescents | |
| Day 82, 8 hours | Family portrait windowEarth and Moon in one 200 mm frame for 2.7 days, 3.63 to 1.00 deg apart; Earth 35 per cent lit (crescent), Moon 37 per cent lit (crescent): two crescents | |
| Day 86, 22 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.3 days, 1.01 to 3.64 deg apart; Earth 37 per cent lit (crescent), Moon 36 per cent lit (crescent): two crescents | |
| Day 95, 7 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.0 days, 3.64 to 1.01 deg apart; Earth 41 per cent lit (crescent), Moon 39 per cent lit (crescent): two crescents | |
| Day 100, 3 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.3 days, 1.00 to 3.65 deg apart; Earth 43 per cent lit (crescent), Moon 45 per cent lit (crescent): two crescents | |
| Day 109, 2 hours | Family portrait windowEarth and Moon in one 200 mm frame for 4.1 days, 3.65 to 1.00 deg apart; Earth 47 per cent lit (crescent), Moon 50 per cent lit (crescent): two crescents | |
| Day 115, 16 hours | Family portrait windowEarth and Moon in one 200 mm frame for 10.6 days, 1.00 to 1.00 deg apart; Earth 52 per cent lit (gibbous), Moon 49 per cent lit (crescent) | |
| Day 128, 13 hours | Family portrait windowEarth and Moon in one 200 mm frame for 4.3 days, 1.00 to 3.66 deg apart; Earth 57 per cent lit (gibbous), Moon 59 per cent lit (gibbous) | |
| Day 136, 13 hours | Family portrait windowEarth and Moon in one 200 mm frame for 4.8 days, 3.66 to 1.00 deg apart; Earth 62 per cent lit (gibbous), Moon 64 per cent lit (gibbous) | |
| Day 143, 21 hours | Family portrait windowEarth and Moon in one 200 mm frame for 10.4 days, 1.00 to 1.01 deg apart; Earth 68 per cent lit (gibbous), Moon 66 per cent lit (gibbous) | |
| Day 156, 8 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.4 days, 1.01 to 3.66 deg apart; Earth 75 per cent lit (gibbous), Moon 77 per cent lit (gibbous) | |
| Day 165, 2 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.7 days, 3.65 to 1.01 deg apart; Earth 82 per cent lit (gibbous), Moon 84 per cent lit (gibbous) | |
| Day 170, 22 hours | Family portrait windowEarth and Moon in one 200 mm frame for 3.5 days, 1.00 to 3.65 deg apart; Earth 87 per cent lit (gibbous), Moon 86 per cent lit (gibbous) | |
| Day 178, 12 hours | Family portrait windowEarth and Moon in one 200 mm frame for 1.5 days, 3.65 to 2.47 deg apart; Earth 92 per cent lit (gibbous), Moon 91 per cent lit (gibbous) |
What this shows
The line is one trajectory produced by the Distant Light mission-geometry simulator: Earth, Moon and Sun as point masses, a single impulsive trans-lunar injection, and no corrections after it. Trans-lunar injection is simulated at 2030-07-27T00:00:00.000 UTC with an ideal impulse of 3,140.154 m/s, giving a characteristic energy of -1.929258738 km2/s2. Closest approach comes 4.47 days later at 6,499 km, on the far side of the Moon at 1.4154 km/s.
The camera view is rendered from the spacecraft's position on a 13.2 mm sensor, so the phases, the occultation and the Earth-above-the-limb composition are the geometry rather than a diagram. Inside a photograph window it uses the lens the composition is scored at: 100 mm for the Earthrise, whose window lasts 402 seconds here. In the story, the move into the camera at Earthrise is an illustrative view from outside the spacecraft; everything after it is the camera.
Later, from far enough away, Earth and the Moon fit in one 200 mm frame. This run has 18 windows of that, 66.6 days in total.
Now studying: the trajectory and the photographs it could make.
Next: independent mission analysis, a realistic spacecraft budget, and discussions with transport and communications providers.
No launch has been booked. Images are concepts or labelled simulations.
What it is not
This is not a flight design. The drawn trajectory leaves out solar radiation pressure and attitude dynamics: the spacecraft is turned to face its imaging target as a drawing convention. Bodies are spheres, lunar libration is not modelled, and the craft is an artist's concept rather than a hardware design. A station pass is a time when the station can see the spacecraft, not a booked contact.
By the end of the run the spacecraft is 4.88 M km from Earth.
The reference design is a double lunar swingby: first lunar flyby, two close returns towards Earth, second lunar flyby, departure. The Earthrise photograph comes from the first flyby. Every close approach is declared: earthrise flyby at 6,499 km on day 4.5, return perigee 1 at 3,496 km on day 7.9, return perigee 2 at 3,077 km on day 21.8, lunar pass 2 at 818 km on day 31.5. Flown 3,000 times with injection, execution and navigation errors (seed 20300911, case design-c-v1), it departs the Earth-Moon region within 180 days in 3,000 of 3,000 runs: 100.00 per cent, 95 per cent interval 99.88 per cent to 100.00 per cent. Among the 3,000 runs that reached the second pass, the 0.1 percentile altitude was 791 km; runs that hit the Moon, re-entered or missed the pass are counted in the outcome table, not in that figure. The corrections cost 41 m/s at the 99th percentile of the per-run total, an impulsive equivalent under the study controller and not a propulsion requirement.
Earth and cloud maps: NASA Visible Earth, Blue Marble. Lunar map: NASA Scientific Visualization Studio CGI Moon Kit, derived from the Lunar Reconnaissance Orbiter Wide Angle Camera mosaic, NASA/GSFC/Arizona State University. Both public domain.