Orbit of NEA (66391) 1999 KW4

Orbital elements listed here are taken from the JPL Horizons website, and represent the current best solution. The orbit will only be perturbed slightly during the close approach to the Earth, but we still provide the Keplerian elements for both the pre- and post-Earth encounter.

Orbital Elements (Solution JPL#265)

Pre-Earth Encounter Post-Earth Encounter
Epoch 2458619.5 (2019-May-16.0) 2458639.5 (2019-Jun-05.0)
Perihelion Time T = 2019-Mar-22 10:46:42 UT T = 2019-Mar-22 10:31:19 UT
Perihelion Time (JD) T = 2458564.949101 T = 2458564.938410
Orbital Period P = 0.515 yr P = 0.515 yr
Semi-major Axis a = 0.6422 AU a = 0.6423 AU
Perihelion Distance q = 0.1999 AU q = 0.2001 AU
Eccentricity e = 0.6887 e = 0.6885
Inclination (J2000) i = 38.88° i = 38.89°
Ascending Node (J2000) Ω = 244.91° Ω = 244.91°
Argument of Perihelion (J2000) ω = 192.62° ω = 192.63°
Perigee Time t = 2019-May-25 23:04 UT
Perigee Distance Δ = 0.034640 AU
Δ = 5.1800×106 km
Velocity with respect to Earth
at closest approach
21.17 km/s
Min. Orbital Intersection Dist. MOID = 0.013085 AU

Full Orbit From Above

View of (66391) 1999 KW4's pre-encounter orbit as seen from the North ecliptic pole with the asteroid and planets shown at the time of the asteroid's closest approach to Earth. From the JPL Small-Body Database Browser.

View of 1999 KW4's entire orbit.

Orbit in Oblique View

Oblique view of the portion of (66391) 1999 KW4's orbit around perigee, viewed from 30° above the ecliptic plane. The black dot denotes the asteroid's and Earth's positions at perigee (2019-May-25).
Oblique view of 1999 KW4's orbit.
PDF Version

Orbit in Earth Co-Orbital View

The orbit of (66391) 1999 KW4 around perihelion, in the Earth's co-orbital reference frame, as seen from above (top panel) and in the ecliptic plane (bottom panel). The black circle denotes the asteroid's position at perihelion (2019-Mar-22) and the open circles show positions at 30-day intervals.
Plot of 1999 KW4's orbit in Earth-co-orbital frame.
PDF Version