(

provisional designation Provisional designation in astronomy is the naming convention applied to astronomical objects immediately following their discovery. The provisional designation is usually superseded by a permanent designation once a reliable orbit has been calcu ...

) is a

near-Earth object A near-Earth object (NEO) is any small Solar System body orbiting the Sun whose closest approach to the Sun ( perihelion) is less than 1.3 times the Earth–Sun distance (astronomical unit, AU). This definition applies to the object's orbit a ...

with a diameter of 1.4 kilometers 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 which is large enough to cause significant regional damage in the event of impact. Th ...

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. It is privately-owned by a consortium of investors including The Vistria Grou ...

. It has a well determined orbit with an

observation arc In observational astronomy, the observation arc (or arc length) of a Solar System body is the time period between its earliest and latest observations, used for tracing the body's path. It is usually given in days or years. The term is mostly use ...

of 64 years including

precovery In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of a celestial object in images or photographic plates predating its discovery, typically for the purpose of calculating a more accurate orbit. This ha ...

images by

Palomar Observatory The Palomar Observatory is an astronomical research observatory in the Palomar Mountains of San Diego County, California, United States. It is owned and operated by the California Institute of Technology (Caltech). Research time at the observat ...

dating back to 1954. became the first object observed by

NASA The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the federal government of the United States, US federal government responsible for the United States ...

's NEO program to be assigned a positive rating on both the

Torino scale The Torino scale is a method for categorizing the impact hazard associated with near-Earth objects (NEOs) such as asteroids and comets. It is intended as a communication tool for astronomers and the public to assess the seriousness of collision p ...

and the

Palermo scale The Palermo scale or Palermo technical impact hazard scale is a logarithmic scale used by astronomers to rate the potential hazard of impact of a near-Earth object (NEO). It combines two types of data—probability of impact and estimated k ...

for a small chance of an impact on 1 February 2019, however it passed Earth at roughly on 13 January 2019 with an uncertainty region of around ±108 km.

Discovery

It was discovered on 9 July 2002 by the

Lincoln Near-Earth Asteroid Research The Lincoln Near-Earth Asteroid Research (LINEAR) project is a collaboration of the United States Air Force, NASA, and the Massachusetts Institute of Technology's Lincoln Laboratory for the systematic detection and tracking of near-Earth object ...

team (LINEAR) at the U.S. Lincoln Laboratory Experimental Test Site near Socorro, New Mexico. At the time of discovery it only had a 6-day observation arc of 9–14 July, which poorly constrained possible future positions of the asteroid. Despite inflammatory press reports, the object had a "low probability" of impact, approximately one in a million, for 1 February 2019. On 22 July 2002,

NEODyS NEODyS (Near Earth Objects Dynamic Site) is an Italian service that provides information on near-Earth objects with a Web-based interface. It is based on a continually and (almost) automatically maintained database of near earth asteroid orbits. T ...

posted a positive 0.18 Palermo scale rating. Further observations, especially from

Erich Meyer Erich Meyer (born 6 August 1951) is an Austrian engineer, amateur astronomer and discoverer of asteroids. Astronomical career Between 1996 and 1999, using the private observatory Meyer/Obermair in Davidschlag (municipality Kirchschlag bei Li ...

, quickly lowered the probability

On 25 July 2002, the hazard rating on the Palermo scale was lowered to −0.25. However, the discovery of the object with an initial Palermo scale rating of 0.06 was a historical event for the NEO observation program. was removed from the Sentry (monitoring system), Sentry Risk Table on 1 August 2002 (23 days after discovery), meaning there is no risk of an impact by it in the next 100 years. On 13 January 2019, the asteroid safely passed from Earth with a 3-sigma uncertainty region of about ±108 km. Between 1900 and 2195 the closest approach to Earth will occur on 15 January 2099 at a distance of roughly with an uncertainty region of about ±430 km. On 30 January 2020, the asteroid safely passed from

2 Pallas Pallas (minor-planet designation: 2 Pallas) is the List of largest asteroids, third-largest asteroid in the Solar System by volume and mass. It is the second asteroid to have been discovered, after 1 Ceres, Ceres, and is likely a remnant ...

References

External links

Simulation of the shrinking uncertainty region for 2019 Jan 28
Peter Thomas * * * {{DEFAULTSORT:2002 NT7 089959 089959 089959 089959 20190113 20020709