Sanchez Net 2022 EEM near-ballistic Earth-Mars cycler (Fig. 2a Cycler 1)

sanchez-net-2022-eem-cycler1 · source: literature · validation: V0

Signature

Bodies: E-M
Primary: Sun (default — heliocentric)
Sequence (canonical): E-E-M
Sense: outbound
Orbit class: Cycler
strict cycler (infinite returns)
Cycler class: multi-arc
Trajectory regime: ballistic
Maintenance ΔV band: unclassified
Model assumption: analytic-ephemeris
Mid-fidelity: real eccentricity / inclination retained; not full N-body.
Period: 4.280 yr (2 × E-M synodic)
Period is the Mars-to-Mars repeat interval in the repeating phase; first cycle (events 3->6) spans ~6.3 yr = 3 syn due to the initial launch phase. The 4.28 yr steady-state repeat (events 6->9) confirms k=2.
Maintenance ΔV: 0.005 km/s — near-ballistic (powered nudge)
Priority date: 2022-05-01

V∞ at encounters

E (encounter 1): 4.28 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 2 (Earth flyby 11/13/2032): v∞ = 4.283 km/s.
M (encounter 2): 6.21 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 3 (Mars flyby 07/09/2035): v∞ = 6.207 km/s.
E (encounter 3): 3.60 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 4 (Earth flyby 11/22/2035): v∞ = 3.605 km/s. Δv = 5 m/s at this event (near-ballistic maneuver).
E (encounter 4): 3.71 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 5 (Earth flyby 05/20/2036): v∞ = 3.709 km/s.
M (encounter 5): 5.21 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 6 (Mars flyby 10/25/2041): v∞ = 5.210 km/s.
E (encounter 6): 5.22 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 7 (Earth flyby 07/07/2042): v∞ = 5.225 km/s.
E (encounter 7): 5.23 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 8 (Earth flyby 07/18/2044): v∞ = 5.234 km/s.
M (encounter 8): 7.28 km/s
SOURCED: Sanchez Net 2022 Fig. 2a event 9 (Mars flyby 02/06/2046): v∞ = 7.276 km/s.

Cycle-level identity (multi-arc invariants)

Aphelion ratio (AR): —
Turn ratio (TR): —
Transit times (days): 136 d, 255 d

Multi-arc patched-conic: each arc is a separate heliocentric ellipse. No single (a,e,i) characterises the full trajectory. Launch declination Dec. = 43.7 degrees is sourced from Fig. 2a caption (launch condition, not a cycler element). No per-arc orbital elements are tabulated in the paper.

Orbit view 2.5D ecliptic projection

spacecraft: analytic-ephemeris (real e/i retained) planets: J2000 osculating ellipse (Standish & Williams Table 1) orientation: coplanar-idealized (no Ω/ω published — in-plane ellipse)

3D view not available for multi-arc trajectories yet. The 3D system can now render a numerically-sampled polyline (n-body or multi-arc), but no sampled trajectory is published for this row — each leg is a separate ellipse with honest gaps where elements are unpublished (the 2D view above shows them). The button will appear here once a sampled path is exported for this trajectory; we never interpolate one from the catalogue's per-leg (a, e).

— — planet orbit (true J2000 ellipse)

Not-published gaps (never interpolated):

E → E — segment elements (a, e) not published; no curve drawn.
E → M — segment elements (a, e) not published; no curve drawn.
M → E — segment elements (a, e) not published; no curve drawn.
E → E — segment elements (a, e) not published; no curve drawn.
E → M — segment elements (a, e) not published; no curve drawn.
M → E — segment elements (a, e) not published; no curve drawn.
E → E — segment elements (a, e) not published; no curve drawn.
E → M — segment elements (a, e) not published; no curve drawn.
M → E — segment elements (a, e) not published; no curve drawn.

Real DE440 encounter dates (5)

2026-11-20 V∞ 4.11 / 6.46 km/s
2028-12-29 V∞ 3.67 / 6.01 km/s
2031-01-18 V∞ 3.20 / 6.50 km/s
2031-02-27 V∞ 4.16 / 4.21 km/s
2033-02-26 V∞ 4.26 / 5.71 km/s

Real, verifiable JPL DE440 geometric-match dates (see Launch windows). Positions on the map are idealized; these are the true dates.

Legs (trajectory segments)

E → E: 186 d, 0 revs
Initial Earth-to-Earth arc (launch to first Earth flyby). ToF derived from Fig. 2a dates.
E → M: 968 d, 0 revs
Earth flyby to first Mars flyby. ToF derived from Fig. 2a dates.
M → E: 136 d, 0 revs
First Mars flyby to Earth flyby. ToF derived from Fig. 2a dates. Δv = 5 m/s near-ballistic maneuver at arrival Earth flyby.
E → E: 180 d, 0 revs
Earth-to-Earth arc between first and second Mars cycle. ToF derived from Fig. 2a dates.
E → M: 1984 d, 0 revs
Earth flyby to second Mars flyby. ToF derived from Fig. 2a dates. This long leg (~5.4 yr) reflects the patched-conic phase of the repeating cycle.
M → E: 255 d, 0 revs
Second Mars flyby to Earth flyby. ToF derived from Fig. 2a dates.
E → E: 742 d, 0 revs
Earth-to-Earth arc in the repeating cycle. ToF derived from Fig. 2a dates.
E → M: 568 d, 0 revs
Earth flyby to third Mars flyby. ToF derived from Fig. 2a dates.
M → E: 1223 d, 0 revs
Third Mars flyby to final Earth flyby (end of 3-cycle trajectory). ToF derived from Fig. 2a dates.

Definition status

incomplete — core fields missing or known-unknowns tracked below

Family: Sanchez Net 2022 EEM near-ballistic Earth-Mars cycler set · Sanchez Net EEM patched-conic

Known-unknowns (5)

Values we expect to exist but have not yet filled (distinct from "not applicable"). Tracked per upstream docs/spec.md §16.6.4.

orbit_elements [unknown]
Per-arc and aggregate (a,e,i) not published in Sanchez Net 2022. This is a patched-conic real-date trajectory from JPL STAR; orbital elements for each arc are not tabulated. Do not compute from launch conditions.

source: Sanchez Net et al. 2022, JSR 59(3):861-870, DOI 10.2514/1.A35091
trajectory.segments[me-leg3].tof_days [derive]
ToF for the final Mars-to-Earth leg (event 9 to event 10) is derived from Fig. 2a dates (1223 days). Event 10 (Earth flyby 06/13/2049, v∞ 7.285 km/s) ends the 3-cycle trajectory and is not part of the repeating cycle. ToF is included for completeness but is not a steady-state cycler parameter.

source: Sanchez Net 2022 Fig. 2a event dates
trajectory.segments[*].n_revs [unknown]
Revolution counts for each segment arc not tabulated; derivable from patched-conic propagation but not published.

source: Sanchez Net et al. 2022, JSR 59(3):861-870
trajectory.maneuvers[me-leg1->ee-leg1].periapsis_alt_km [unknown]
Altitude at event 4 Earth flyby (11/22/2035) not legible from Fig. 2a at available resolution.

source: Sanchez Net 2022 Fig. 2a event 4
trajectory.epoch_tzero [unverified-provenance]
The epoch is given as a Gregorian calendar date from Fig. 2a; exact UTC/TDB offset and MJD equivalent are not published. epoch_tzero is set to the ISO-8601 date string (2032-05-11) as a best approximation.

source: Sanchez Net 2022 Fig. 2a event 1

Primary citation

Sanchez Net, M. et al. (2022). Cycler Orbits and Solar System Pony Express. Journal of Spacecraft and Rockets, Vol. 59, No. 3, pp. 861-870, May-June 2022.

DOI: 10.2514/1.A35091

Fig. 2a (p. 862) provides the full event list, dates, v∞ values, altitudes, and Δv for Cycler 1 ('1 Mars visit every 2 synodic periods'). The trajectory was generated by the JPL STAR patched-conic tool with unoptimised per-flyby Δv ≤ 10 m/s.

Notes

Sanchez Net 2022 Fig. 2a Cycler 1. Near-ballistic EEM Earth-Mars cycler from the JPL STAR patched-conic enumeration. Launch: 05/11/2032, C∞ = 17.6 km²/s², Dec. = 43.7 degrees (sourced from Fig. 2a caption). Three Mars visits over 15 years (events 3, 6, 9). Max unoptimised Δv = 5 m/s (event 4). The trajectory is not circular-coplanar; it uses real date ephemeris (analytic-ephemeris model). The first Mars-to-Mars interval (events 3->6) is ~6.3 yr = ~3 synodic periods; the second (events 6->9) is ~4.28 yr = ~2 synodic periods. The paper caption states "1 Mars visit every 2 synodic periods" referring to the repeating steady-state period (k=2). The initial longer interval is a phase-matching artefact of the 2032 launch epoch. V∞ multiset (from Fig. 2a, per encounter): Earth encounters 4.283, 3.605, 3.709, 5.225, 5.234 km/s; Mars encounters 6.207, 5.210, 7.276 km/s. Launch v∞ ≈ 4.20 km/s (C∞ = 17.6 km²/s²).

Source quotes (per-field provenance)

Every numerical value in this entry traces to a verbatim or paraphrased quote from a cited source.

delta_v_kms: Sanchez Net 2022 Fig. 2a event 4: '5 m/s' (near-ballistic maneuver at Earth flyby 11/22/2035).
period.years: Sanchez Net 2022 Fig. 2a caption: '1 Mars visit every 2 synodic periods'. Events 6 (10/25/2041) to 9 (02/06/2046) = 1565 days = 4.28 yr ≈ 2 × 2.135 yr.
vinf_kms_at_encounters[E/4.283]: Sanchez Net 2022 Fig. 2a event 2 (Earth flyby 11/13/2032): v∞ = 4.283 km/s.
vinf_kms_at_encounters[M/6.207]: Sanchez Net 2022 Fig. 2a event 3 (Mars flyby 07/09/2035): v∞ = 6.207 km/s.
vinf_kms_at_encounters[E/3.605]: Sanchez Net 2022 Fig. 2a event 4 (Earth flyby 11/22/2035): v∞ = 3.605 km/s.
vinf_kms_at_encounters[E/3.709]: Sanchez Net 2022 Fig. 2a event 5 (Earth flyby 05/20/2036): v∞ = 3.709 km/s.
vinf_kms_at_encounters[M/5.210]: Sanchez Net 2022 Fig. 2a event 6 (Mars flyby 10/25/2041): v∞ = 5.210 km/s.
vinf_kms_at_encounters[E/5.225]: Sanchez Net 2022 Fig. 2a event 7 (Earth flyby 07/07/2042): v∞ = 5.225 km/s.
vinf_kms_at_encounters[E/5.234]: Sanchez Net 2022 Fig. 2a event 8 (Earth flyby 07/18/2044): v∞ = 5.234 km/s.
vinf_kms_at_encounters[M/7.276]: Sanchez Net 2022 Fig. 2a event 9 (Mars flyby 02/06/2046): v∞ = 7.276 km/s.