90568 Goibniu

History

Discovery

Goibniu was discovered on 13 April 2004 by the Near-Earth Asteroid Tracking (NEAT) survey, which was a NASA-directed project for finding near-Earth asteroids in the sky using telescopes at various observatories across the United States. The telescope that discovered Goibniu was the 1.22 m Samuel Oschin telescope at Palomar Observatory in San Diego County, California. The people involved in making the discovery observations at Palomar included Steven Pravdo, D. MacDonald, Kenneth Lawrence and Michael D. Hicks. The discovery of Goibniu was announced by the Minor Planet Center (MPC) on 14 April 2004, after several other observatories observed the object.

Precovery observations of Goibniu were first reported by astronomer Reiner Stoss and published by the MPC on 10 June 2004. These precovery observations, which came from Digitized Sky Survey images from 1993–1997, allowed for an accurate determination of Goibniu's orbit without the need for follow-up observations. Even earlier precovery observations have since been reported, from dates as early as December 1954.

Number and name

This object has the minor planet provisional designation , which was given by the MPC in the discovery announcement. The provisional designation indicates the year and half-month of the object's discovery date. received its permanent minor planet catalog number of 90568 from the MPC on 30 August 2004.

Until 2025, did not have a proper name and the discoverers' privilege for naming this object expired ten years after it was numbered. According to naming guidelines by the International Astronomical Union's Working Group for Small Bodies Nomenclature, was open for name suggestions that relate to creation myths, as recommended for Kuiper belt objects in general. On 1 September 2025, it was officially named Goibniu, after the Irish god of metallurgy and hospitality.

Orbit

Goibniu is a trans-Neptunian object orbiting the Sun at a semi-major axis or average distance of 41.9 astronomical units (AU). It has an orbital eccentricity of 0.08 and an inclination of 22° with respect to the ecliptic. In its 271-year-long orbit, Goibniu comes as close as 38.7 AU from the Sun at perihelion and as far as 45.2 AU from the Sun at aphelion.

Goibniu is located in the classical region of the Kuiper belt 39–48 AU from the Sun, and is thus classified as a classical Kuiper belt object (sometimes known as a "cubewano"). The high orbital inclination of Goibniu makes it a dynamically "hot" member of the classical Kuiper belt. The hot classical Kuiper belt objects are believed to have been scattered by Neptune's gravitational influence during the Solar System's early history.

Physical characteristics

Size

Goibniu has a diameter of 680 ± 34 km, according to measurements of its infrared thermal emission by the Herschel and Spitzer space telescopes. Goibniu is large enough that some astronomers including Noemi Pinilla-Alonso and Michael E. Brown once considered it a possible dwarf planet.

Notes

References

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|display-authors = etal

|author-link=Marc W. Buie

|doi-access = free

|author-link=Michael E. Brown

|chapter-url = https://www.lpi.usra.edu/books/ssbn2008/7002.pdf |url-status = dead |archive-url = https://web.archive.org/web/20230801104434/https://www.lpi.usra.edu/books/ssbn2008/7002.pdf |archive-date = 1 August 2023}}

|doi-access = free

|doi-access = free

|display-authors = etal |url-status = dead |archive-url = https://web.archive.org/web/20250330030249/https://www.lpi.usra.edu/decadal/sbag/community_wp/SB_Community_WP_Final_Dwarfs.pdf |archive-date = 2025-03-30}}

|display-authors = etal |doi-access = free

|editor-first1 = Dina |editor-last1 = Prialnik |editor-first2 = Maria Antonietta |editor-last2 = Barucci |editor-first3 = Leslie |editor-last3 = Young

References

1. Tegler, Stephen C.. (2007-02-01). "Kuiper Belt Object Magnitudes and Surface Colors".
2. David L. Rabinowitz. (2008). "The Youthful Appearance of the 2003 EL61 Collisional Family". The Astronomical Journal.