Juno Earth-gravity-assist cruise to Jupiter, SPK-derived V_inf

juno-earth-flyby-jupiter · source: literature · validation: V0

Signature

Bodies: E-E-J
Primary: Sun (default — heliocentric)
Sequence (canonical): E-E-J
Sense: n/a
Orbit class: Tour
MGA tour (one-shot terminal arrival)
Cycler class: multi-arc
Returns: 1 — finite for epoch-locked classes
Validity window: 2011-08-05 → 2016-07-05
Launch epoch: 2011-08-05T16:25:00Z
Trajectory regime: ballistic
Maintenance ΔV band: unclassified
Model assumption: analytic-ephemeris
Mid-fidelity: real eccentricity / inclination retained; not full N-body.
Period: not strictly periodic (no published period)
Source ephemeris: DE440 + NAIF reconstructed Juno cruise SPK (spk_merge_110805_171017_130515.bsp)
Ephemeris model the source states its numbers were computed against.
Priority date: 2011-08-05

V∞ at encounters

E (encounter 1): 10.40 km/s
SPK-derived planetocentric V_inf at the Earth gravity-assist flyby closest approach 2013-10-09T19:21 UTC (spk_merge_110805_171017_130515.bsp, NAIF -61); vis-viva outer-window std 0.003 km/s; CA 1.087 R_E / 552 km alt reproduces the published ~559 km (NSSDCA 2011-040A) to ~1%.

Cycle-level identity (multi-arc invariants)

Aphelion ratio (AR): —
Turn ratio (TR): —
Transit times (days): —

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no sampled trajectory is published for this row — each leg is a separate ellipse with honest gaps where elements are unpublished (the 2D view above shows them).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)

Definition status

incomplete — core fields missing or known-unknowns tracked below

Primary citation

NASA NSSDCA (2011). Juno spacecraft (2011-040A) / Earth flyby parameters. NASA NSSDCA master catalog + NASA Science Juno mission pages.

orbit source derived orbit fidelity real-de440 V∞ source derived V∞ fidelity real-de440

Corroborating sources

Acton, C. H. (1996). Ancillary data services of NASA's Navigation and Ancillary Information Facility (NAIF SPICE). Planetary and Space Science 44(1):65-70. DOI: 10.1016/0032-0633(95)00107-7
Provenance of the reconstructed Juno cruise SPK kernel that the vinf_at_flyby reads; the Earth-flyby V_inf is DERIVED from this authoritative mission kernel.

Notes

Juno's flown Earth-gravity-assist cruise to Jupiter: launched 2011-08-05 into a ~2-year heliocentric loop, a deep-space maneuver at aphelion set up the 2013-10-09 Earth gravity assist that boosted the spacecraft onto its Jupiter transfer, arriving for Jupiter Orbit Insertion 2016-07-05. The single clean gravity-assist flyby (Earth 2013) is the diagnostic encounter; its V_inf is not published in clean form, so we derive it from the mission's archived NAIF reconstructed cruise SPK at the sourced flyby epoch (cyclerfinder.verify.mission_spk.vinf_at_flyby). Earth gravity-assist flyby 2013-10-09T19:21 UTC: V_inf 10.401 km/s, CA 1.087 R_E / 552 km alt (published ~559 km, NSSDCA). Earth departure (2011-08-05) and the terminal Jupiter Orbit Insertion (2016-07-05) carry no V_inf entry: the launch C3 is not assigned a fabricated departure V_inf, and JOI is a retro-capture burn, not a hyperbolic flyby (the symmetric vis-viva extraction does not apply to a capture). Sourced-only discipline. validation_level=V0: Earth-flyby V_inf DERIVED by our own code (orbit_source = vinf_source = derived -> 'unvalidated' provenance tier; V0 on validation_level), even though the CA altitude reproduces the published NSSDCA record to ~1%. The 7th SPK-derived mga_tour row. See docs/notes/2026-06-19-390-spk-vinf-extractor.md.

Source quotes (per-field provenance)

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

launch_epoch: Juno launched 2011-08-05 16:25 UTC from Cape Canaveral (NASA NSSDCA spacecraft 2011-040A).
validity_window.end: Jupiter Orbit Insertion 2016-07-05 03:53 UTC (burn-completion confirmation received at Earth; NASA NSSDCA 2011-040A).
vinf_kms_at_encounters.0.vinf_kms: DERIVED: planetocentric V_inf 10.401 km/s from NAIF SPK spk_merge_110805_171017_130515.bsp (Juno, body -61) at the Earth gravity-assist CA 2013-10-09T19:21 UTC; CA 552 km alt reproduces the published ~559 km (NASA NSSDCA 2011-040A) to ~1%.
n_returns: Single Earth launch (2011-08-05) and single Jupiter arrival (2016-07-05); n_returns=1 per the v4.7 mga_tour invariant (no continuing tour at Earth).