, provisional designation , is a dark and elongated
asteroid
An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere.
...
, classified as
near-Earth object and
potentially hazardous asteroid
A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an orbit that can make close approaches to the Earth and is large enough to cause significant regional damage in the event of impact. They are ...
of the
Apollo group
Apollo Education Group, Inc. is an American corporation based in the South Phoenix area of Phoenix, Arizona, with an additional corporate office in Chicago, Illinois.
The company owns and operates several higher-learning institutions, including ...
, approximately in diameter. It was discovered on 30 September 2014, by NASA's
Wide-field Infrared Survey Explorer telescope (WISE) in Earth's orbit.
Closely observed at
Goldstone and
Arecibo in February 2018, it has a rotation period of 8.7 hours.
Orbit and classification
is a member of the
Apollo asteroids, which
cross the orbit of Earth. Apollo's are the largest group of
near-Earth objects
A near-Earth object (NEO) is any small Solar System body whose orbit brings it into proximity with Earth. By convention, a Solar System body is a NEO if its closest approach to the Sun (perihelion) is less than 1.3 astronomical units (AU). ...
with nearly 10 thousand known objects. It orbits the Sun at a distance of 0.90–1.70
AU once every 18 months (541 days;
semi-major axis
In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...
of 1.30 AU). Its orbit has an
eccentricity of 0.30 and an
inclination of 30
° with respect to the
ecliptic.
With an
aphelion of 1.70 AU, it is also a
Mars-crosser, as it crosses the orbit of the Red Planet at 1.666 AU. The body's
observation arc begins with its official discovery observation by WISE in September 2014.
Close approaches
As a
potentially hazardous asteroid
A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an orbit that can make close approaches to the Earth and is large enough to cause significant regional damage in the event of impact. They are ...
, has a
minimum orbital intersection distance (MOID) with Earth of less than 0.05 AU and a diameter of greater than 150 meters. The Earth-MOID is currently , which translates into 13.8
lunar distances (LD).
2018 flyby
On 7 February 2018 it passed from the Earth when its
apparent magnitude brightened to 14.
observed it until the following day.
While this was an 8.1-million kilometer flyby, the next close flyby of 6.3 million km will occur on 5 February 2058, and another 7.6 million km on 8 February 2095. It will also have a 3.2 million km flyby of Mars on 26 September 2048.
Physical characteristics
The asteroid's
spectral type is unknown. Due to its unusually low albedo ''(see below)'' it is likely a carbonaceous
C-type asteroid.
Rotation period
On 9 February, radiometric observations by the
Arecibo Observatory
The Arecibo Observatory, also known as the National Astronomy and Ionosphere Center (NAIC) and formerly known as the Arecibo Ionosphere Observatory, is an observatory in Barrio Esperanza, Arecibo, Puerto Rico owned by the US National Science F ...
revealed that the asteroid has an elongated, lumpy shape.
The radar images also gave it a
rotational period between 8 and 9 hours.
A refined period of 8.7 hour agrees with (photometric)
lightcurve observations by American photometrist
Brian Warner at the Center for Solar System Studies () during 9–11 February 2018, who obtained a period of 8.729 hours with a high brightness amplitude of 0.93
magnitude, which also indicates a non-spheroidal shape ().
Diameter and albedo
According to the survey carried out by the
NEOWISE mission of NASA's WISE telescope, measures 0.971 kilometers in diameter and its surface has an
albedo of 0.068.
During its close approach in February 2018, radiometric observations by Arecibo Observatory determined that the object is at least wide.
Data from the
Arecibo Telescope
The Arecibo Telescope was a spherical reflector radio telescope built into a natural sinkhole at the Arecibo Observatory located near Arecibo, Puerto Rico. A cable-mount steerable receiver and several radar transmitters for emitting signals wer ...
released in 2022 showed an unusually high radar albedo, possibly indicating rich metal content.
Numbering and naming
This
minor planet was numbered by the
Minor Planet Center
The Minor Planet Center (MPC) is the official body for observing and reporting on minor planets under the auspices of the International Astronomical Union (IAU). Founded in 1947, it operates at the Smithsonian Astrophysical Observatory.
Function
...
on 4 November 2017 ().
As of 2018, it has not been
named.
Gallery
File:2014_SR339_skyview2018.png, Daily motion of asteroid across sky
File:2014_SR339_flyby2018.png, View of flyby above the earth and moon
Notes
References
External links
List of the Potentially Hazardous Asteroids (PHAs) ''Minor Planet Center''
''Minor Planet''
Asteroid Lightcurve Database (LCDB) query form
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Near-Earth objects in 2018
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