2017 OO1


2017 OO1
2017 OO1 orbit-Aug2017.png
The orbit of 2017 OO1 and positions on 8/1/2017
Discovery [1]
Discovered byATLAS-MLO
Discovery siteMauna Loa Obs.
Discovery date23 July 2017
(first observed only)
2017 OO1
NEO · Aten[1][2]
Orbital characteristics[2]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 4
Observation arc9 days
Aphelion1.0173 AU
Perihelion0.7714 AU
0.8943 AU
309 days
1° 9m 55.08s / day
Earth MOID0.0001982 AU (0.0771 LD)
Physical characteristics
Mean diameter
35 m (est. at 0.24)[3]
35–77 m (estimate)[4]
76 m (est. at 0.05)[3]

2017 OO1 is a small asteroid, classified as near-Earth object of the Aten group, approximately 35–76 meters (115–249 feet) in diameter. It was first observed on 23 July 2017, by the robotic ATLAS survey at Mauna Loa Observatory, Hawaii, two days after the object had approached Earth at 0.33 lunar distances on 21 July 2017.[1][2]

Orbit and classification

2017 OO1 is a member of the Aten asteroid, a subgroup of near-Earth objects that are located in the zone of influence of Venus. Atens are a much smaller group than the Apollo and Amor asteroids.

The object has an exceptionally low minimum orbital intersection distance with Earth of 29,650 kilometers or 0.077 lunar distances (LD).[2] It orbits the Sun at a distance of 0.77–1.02 AU once every 10 months (309 days; semi-major axis of 0.89 AU). Its orbit has an eccentricity of 0.14 and an inclination of 20° with respect to the ecliptic.[2] The body's observation arc begins with an observation made by the space-based Wide-field Infrared Survey Explorer on 22 July 2017, one day after its close flyby and a day before its official first observation.[1]

Close approaches

On 21 July 2017, at 03:32 UT, it flew past Earth at a nominal distance of 127,500 kilometers (0.33 LD) with a relative velocity of 10.36 km/s.[4] All future encounters with Earth will occur at a significantly larger distance.[2]

The objects trajectory inside the orbit of the Moon (left), and its path in the sky during flyby, seen from the center of the Earth

Physical characteristics

Based on a generic magnitude-to-diameter conversion, 2017 OO1 measures between 35–76 meters (115–249 feet) in diameter, for an absolute magnitude of 24.5, and an assumed albedo between 0.05 and 0.24, which represent typical values for carbonaceous and stony asteroids, respectively.[3] As of 2018, no rotational lightcurve has been obtained from photometric observations. The body's rotation period, pole and shape remain unknown.[2]

Numbering and naming

This minor planet has neither been numbered nor named by the Minor Planet Center.[1]


  1. ^ a b c d e "2017 OO1". Minor Planet Center. Retrieved 21 March 2018.
  2. ^ a b c d e f g h "JPL Small-Body Database Browser: (2017 OO1)" (2017-07-31 last obs.). Jet Propulsion Laboratory. Retrieved 21 March 2018.
  3. ^ a b c "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 21 March 2018.
  4. ^ a b "Asteroid 2017 OO1 flew past Earth at a very close distance of 0.33 LD". The Watchers. 25 July 2017. Retrieved 21 March 2018.

External links

  • MPEC 2017-O52 : 2017 OO1, Minor Planet Electronic Circular
  • List Of Aten Minor Planets (by designation), Minor Planet Center
  • Close shave from an undetected asteroid, EarthSky, 25 July 2017
  • Asteroid 2017 OO1 close approach, International Asteroid Warning Network (IAWN)
  • Trajectory Diagram, Minor Planet Center
  • 2017 OO1 at NeoDyS-2, Near Earth Objects—Dynamic Site
    • Ephemeris · Obs prediction · Orbital info · MOID · Proper elements · Obs info · Close · Physical info · NEOCC
  • 2017 OO1 at the JPL Small-Body Database
    • Close approach · Discovery · Ephemeris · Orbit diagram · Orbital elements · Physical parameters