2014 PN70 (internally designated g12000JZ, g1 and PT3) is a trans-Neptunian object from the cold classical Kuiper belt located in the outermost region of the Solar System. It measures approximately 40 kilometers (25 miles) in diameter. The object was first observed by the New Horizons Search Team using the Hubble Space Telescope on 6 August 2014, and was a proposed flyby target for the New Horizons probe until 2015, when the alternative target 486958 Arrokoth was selected.[2]

2014 PN70
2014 PN70, imaged by the Hubble Space Telescope in May 2015
Discovery[1]
Discovered byNew Horizons KBO Search
Discovery siteHubble Space Telescope
Discovery date6 August 2014
(first observed only)
Designations
2014 PN70
g12000JZ · g1 · PT3[2]
TNO[3] · cubewano[4][5]
distant[1]
Orbital characteristics[1]
Epoch 27 April 2019 (JD 2458600.5)
Uncertainty parameter 2
Observation arc0.86 yr (313 days)
Aphelion47.047 AU
Perihelion42.033 AU
44.540 AU
Eccentricity0.05628
297 yr (108,405 d)
288.081°
0° 0m 11.937s / day
Inclination4.111°
136.354°
228.068°
Physical characteristics
Mean diameter
30–55 km[6]
35–55 km[7]
39 km (estimate)[5]
44 km (est. at 0.07)[8]
12.05 h[9]
0.04–0.10[7]
0.04–0.15[6]
V–I = 1.34[10]
26.1[10]
10.3[3]

Discovery and designations edit

 
The orbits of New Horizons potential targets 1–3. 2014 PN70 is in green. 2014 OS393 (PT2) is in red. 486958 Arrokoth (PT1) is in blue.

2014 PN70 was discovered by the New Horizons Search Team during an observation campaign intended to search for KBO flyby targets for the New Horizons probe.[11] The observations started in June 2014, and more intensive ones continued in July and August.[12] They were conducted with the help of the Hubble Space Telescope; the object's apparent magnitude of 26.4 is too faint to be observed by ground-based telescopes. 2014 PN70 was first discovered in observations on August 6, 2014, and it was designated g12000JZ at the time, nicknamed g1 for short.[2][6] Its existence as a potential target of the New Horizons probe was revealed by NASA in October 2014[13][14] and it was designated PT3; its official provisional designation, 2014 PN70, was not assigned by the Minor Planet Center until March 2015 after better orbit information was available.[2]

Orbit and classification edit

2014 PN70 is a trans-Neptunian object. More specifically, it is a non-resonant classical Kuiper belt object, also known as "cubewano". It orbits the Sun at a distance of 42.1–46.6 AU once every 295 years and 4 months (107,886 days; semi-major axis of 44.4 AU). Its orbit has an eccentricity of 0.05 and an inclination of 4° with respect to the ecliptic.[3] This makes it a typical member of the "cold population" among the cubewanos in the Kuiper belt.

The body's observation arc begins with a precovery taken by the New Horizons KBO Search team with the Subaru Telescope at Mauna Kea Observatory on Hawaii, six week prior to its official first observation by Hubble.[1]

Numbering and naming edit

This minor planet has not been numbered by the Minor Planet Center and remains unnamed.[1]

Physical characteristics edit

2014 PN70, has a diameter approximately 35–55 km (22–34 mi), based on an estimated albedo between 0.04 and 0.10 respectively.[7] Astronomer Marc Buie gives a similar estimate of 30–55 km (19–34 mi), and the Johnston's archive calculated a diameter of 39 km.[5] Based on generic magnitude-to-diameter conversion, the object measures 44 km, for an absolute magnitude of 10.3 and an assumed albedo of 0.07.[8] Hubble observations of 2014 PN70 show that it is very red in color.[10]

Exploration edit

 
Trajectory of New Horizons and other nearby Kuiper belt objects
 
2014 PN70, imaged in January 2019 by the New Horizons space probe from a distance of 93 million km

Having completed its flyby of Pluto, the New Horizons space probe was to perform a flyby of at least one Kuiper belt object. Several potential targets were under consideration. 2014 PN70 (PT3) was considered a second choice after 2014 MU69 (PT1), because more fuel was required to carry out a flyby. 2014 OS393 (PT2) was already no longer under consideration as a potential target.[15] On 28 August 2015, the New Horizons team announced the selection of 2014 MU69 (later named 486958 Arrokoth) as the next flyby target.[16]

2014 PN70 is one of the objects that New Horizons observed from greater distances, as part of its extended Kuiper belt mission. The spacecraft passed 2014 PN70 in March 2019, at a distance of approximately 0.1 AU (15 million km; 9.3 million mi). This made 2014 PN70 the third closest KBO observed by New Horizons, after Arrokoth and 2014 OS393.[17] New Horizons made its first observations of 2014 PN70 on 5 January 2019, from a distance of 92.7 million km.[18]

New Horizons did not come close enough to resolve either 2014 PN70 or 2014 OS393, but the observations should be sufficient to determine the rotation periods and surface properties of these objects and to search for possible satellites. The distant KBO observations provide an important context for the data collected during the close flyby of Arrokoth.[19]

See also edit

References edit

  1. ^ a b c d e "2014 PN70". Minor Planet Center. Retrieved 9 February 2018.
  2. ^ a b c d Zangari, Amanda (28 March 2015). "Postcards from Pluto". Tumblr.
  3. ^ a b c "JPL Small-Body Database Browser: (2014 PN70)" (2014-10-22 last obs.). Jet Propulsion Laboratory. Retrieved 9 February 2018.
  4. ^ Marc W. Buie. "Orbit Fit and Astrometric record for 14PN70". SwRI (Space Science Department). Retrieved 18 February 2018.
  5. ^ a b c Johnston, Wm. Robert (30 December 2017). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 9 February 2018.
  6. ^ a b c Buie, Marc (15 October 2014). "New Horizons HST KBO Search Results: Status Report" (PDF). Space Telescope Science Institute. p. 23. Archived from the original (PDF) on 27 July 2015.
  7. ^ a b c Lakdawalla, Emily (15 October 2014). "Finally! New Horizons has a second target". Planetary Society blog. Planetary Society. Archived from the original on 15 October 2014.
  8. ^ a b "Asteroid Size Estimator". CNEOS NASA/JPL. Retrieved 9 February 2018.
  9. ^ Verbiscer, Anne; Porter, Simon; Kavelaars, J.; Helfenstein, Paul; Benecchi, Susan; Weaver, Harold; et al. (October 2021). Putting (486958) Arrokoth in Context: New Horizons Observations of Other Small Cold Classical Kuiper Belt Objects. 53rd Annual DPS Meeting. Vol. 53. American Astronomical Society. Bibcode:2021DPS....5330701V. 307.01.
  10. ^ a b c Benecchi, S. D.; Borncamp, D.; Parker, A. H.; Buie, M. W.; Noll, K. S.; Binzel, R. P.; et al. (December 2019). "The color and binarity of (486958) 2014 MU69 and other long-range New Horizons Kuiper Belt targets". Icarus. 334: 22–29. arXiv:1812.04752. doi:10.1016/j.icarus.2019.01.025. S2CID 119192900.
  11. ^ J. R. Spencer; M. W. Buie; et al. (2015). "The Successful Search for a Post-Pluto KBO Flyby Target for New Horizons Using the Hubble Space Telescope" (PDF). European Planetary Science Congress (EPSC) Abstract. Copernicus Office: EPSC2015-417. Bibcode:2015EPSC...10..417S.
  12. ^ "Hubble to Proceed with Full Search for New Horizons Targets". HubbleSite news release. Space Telescope Science Institute. 1 July 2014.
  13. ^ "NASA's Hubble Telescope Finds Potential Kuiper Belt Targets for New Horizons Pluto Mission". HubbleSite. 15 October 2014.
  14. ^ Wall, Mike (15 October 2014). "Hubble Telescope Spots Post-Pluto Targets for New Horizons Probe". Space.com. Archived from the original on 15 October 2014.
  15. ^ Powell, Corey S. (29 March 2015). "Alan Stern on Pluto's Wonders, New Horizons' Lost Twin, and That Whole "Dwarf Planet" Thing". Discover. Archived from the original on 16 November 2019. Retrieved 8 May 2015.
  16. ^ Cofield, Calla (28 August 2015). "Beyond Pluto: 2nd Target Chosen for New Horizons Probe". Space.com.
  17. ^ S. A. Stern; H. A. Weaver; J. R. Spencer; H. A. Elliott (2016). "The New Horizons Kuiper Belt Extended Mission". Space Science Reviews. 214 (4). arXiv:1806.08393. doi:10.1007/s11214-018-0507-4. S2CID 119506499.
  18. ^ "NH LORRI KEM1". pdssbn.astro.umd.edu. Planetary Data System. 18 October 2019. Retrieved 27 June 2020.
  19. ^ Alan Stern (14 April 2016). "To Boldly Go On, In the Service of Exploration". pluto.jhuapl.edu. Retrieved 22 September 2018.

External links edit