(523731) 2014 OK394
 | |
| Discovery[1] | |
|---|---|
| Discovered by | Spacewatch |
| Discovery site | Kitt Peak Obs. |
| Discovery date | 20 September 1995 |
| Designations | |
| 1995 SN55[1] | |
| 3:5 resonant[2] · TNO[3] · distant[1] | |
| Orbital characteristics[3] | |
| Epoch 9 June 2026 (JD 2461200.5) | |
| Uncertainty parameter 2 | |
| Observation arc | 21.10 yr (7,708 days) |
| Aphelion | 49.698 AU |
| Perihelion | 35.528 AU |
| 42.613 AU | |
| Eccentricity | 0.166 |
| 278.18 yr | |
| 36.246° | |
| 0° 0m 12.755s / day | |
| Inclination | 4.134° |
| 128.550° | |
| ≈ 4 January 1997[4] | |
| 250.384° | |
| Known satellites | 0 |
| Physical characteristics | |
| 160–280 km (est. 0.08–0.20)[5][6] | |
| 6.2[1][3] | |
(523731) 2014 OK394, also known as 1995 SN55, is a trans-Neptunian object located in the Kuiper belt.[7] It orbits the Sun in a 3:5 orbital resonance with Neptune, meaning it completes three orbits for every five completed by Neptune. It was discovered by Spacewatch at Kitt Peak, Arizona on 20 September 1995, but astronomers lost track of it for over a decade. It was unknowingly rediscovered by Pan-STARRS in 2010 and was later linked back to Spacewatch's 1995 discovery in 2020.
Discovery
[edit]The object was discovered twice and therefore has two provisional designations.[1] It was first discovered on 20 September 1995 by astronomers Nichole Danzl and Arianna Gleason of the Spacewatch survey at Kitt Peak Observatory in Arizona, United States.[8] However, it was only observed 14 times over 36 days, from 20 September to 26 October 1995.[9] The object was never seen again and thus became a lost minor planet.[10] The Minor Planet Center (MPC) gave it the provisional designation 1995 SN55 and published the discovery observations on 11 June 1999.[8] Due to the sparse amount of observations, 1995 SN55's calculated orbit was extremely uncertain.[9] Astronomers had speculated that 1995 SN55 might either be one of the largest known centaurs, a temporarily brightening object, or a false positive caused by image noise.[10]
On 8 October 2010, the object was unknowingly rediscovered by the Pan-STARRS 1 survey at Haleakalā Observatory, Hawaii.[11] Pan-STARRS continued observing the object until 2015, and the MPC later announced its discovery with the provisional designation 2014 OK394 on 17 July 2016.[11] In 2018, after the object's orbit was securely determined, the MPC assigned the official discovery credit to Pan-STARRS.[12] On 30 November 2020, amateur astronomers S. Deen and K. Ly identified 2014 OK394 as being the same object as 1995 SN55.[13] This identification was published by the MPC on 27 January 2021[14] and the object's discoverer was later changed to Spacewatch.[1]
Numbering and naming
[edit]2014 OK394 was numbered by the MPC on 25 September 2018 and received the number 523731 in the minor planet catalog.[12] The provisional designation 1995 SN55 was added by the MPC on 27 January 2021 after the two discoveries were linked.[14] As of 2026[update], it has not been named.[1]
Classification and orbit
[edit]
2014 OK394 orbits the Sun with an average distance (semi-major axis) of 42.6 astronomical units (AU) and an orbital period of 278 years.[3] It is located in the Kuiper belt, a region of the Solar System beyond Neptune where many other icy minor planets are found. 2014 OK394's orbit has an eccentricity of 0.17 and an inclination of 4° with respect to the ecliptic plane.[3] Over the course of its orbit, its distance from the Sun ranges from 35.5 AU at perihelion to 49.7 AU at aphelion.[3] 2014 OK394 is in a 3:5 mean-motion orbital resonance with Neptune, meaning it completes three orbits every time Neptune completes five.[2][7] Its orbit has a minimum orbit intersection distance approximately 5.8 AU (870 million km; 540 million mi) from Neptune's orbital path.[1]
Physical characteristics
[edit]Little is known about 2014 OK394's physical characteristics. Johnston's Archive estimates a diameter of 217 km (135 mi) assuming a geometric albedo of 0.126,[2] whereas Michael E. Brown estimates a diameter of 160 km (99 mi) for an assumed albedo of 0.20.[5] A 2024 study led by Audrey Thirouin and Scott Sheppard found that 2014 OK394 exhibits little variability in brightness over four hours of observations, with a light curve amplitude of roughly 0.05 magnitude.[7]
See also
[edit]- Lost minor planet
- (392741) 2012 SQ31 – main-belt asteroid originally misidentified as a trans-Neptunian object
References
[edit]- 1 2 3 4 5 6 7 8 "(523731) = 1995 SN55 = 2014 OK394". Minor Planet Center. International Astronomical Union. Archived from the original on 30 November 2020. Retrieved 1 August 2026.
- 1 2 3 Johnston, Wm. Robert (18 August 2020). "List of Known Trans-Neptunian Objects". Johnston's Archive. Retrieved 24 February 2021.
- 1 2 3 4 5 6 "JPL Small-Body Database Lookup: 523731 (2014 OK394 = 1995 SN55)" (2026-01-21 last obs.). Jet Propulsion Laboratory. Archived from the original on 30 November 2020. Retrieved 1 August 2026.
- ↑ "JPL Horizons On-Line Ephemeris for 523731 (2014 OK394 = 1995 SN55)". JPL Horizons On-Line Ephemeris System. Jet Propulsion Laboratory. Retrieved 10 February 2021.
Ephemeris Type: OBSERVER, Target Body: 523731 (2014 OK394), Observer Location: Sun (body center) [500@10], Table Settings: QUANTITIES=20. Observer range
(Perihelion occurs when deldot changes from negative to positive.) - 1 2 Brown, Michael E. (23 February 2021). "How many dwarf planets are there in the outer solar system?". California Institute of Technology. Retrieved 24 February 2021.
- ↑ Bruton, Dan. "Conversion of Absolute Magnitude to Diameter for Minor Planets". Department of Physics, Engineering, and Astronomy. Stephen F. Austin State University. Archived from the original on 23 July 2011. Retrieved 24 February 2021.
- 1 2 3 Thirouin, Audrey; Sheppard, Scott S. (April 2024). "Rotational Study of 5:3 and 7:4 Resonant Objects within the Main Classical Trans-Neptunian Belt". The Planetary Science Journal. 5 (4): 84. arXiv:2402.05269. Bibcode:2024PSJ.....5...84T. doi:10.3847/PSJ/ad2933.
- 1 2 Marsden, Brian G. (11 June 1999). "MPEC 1999-L25 : 1995 SN55, 1998 TF35". Minor Planet Electronic Circular. 1999-L25. Minor Planet Center. Bibcode:1999MPEC....L...25D. Retrieved 30 November 2020.
- 1 2 "JPL Small-Body Database Browser: (1995 SN55)" (1995-10-26 last obs.). Jet Propulsion Laboratory. Archived from the original on 30 November 2020. Retrieved 24 February 2021.
(Archive of 36 day observation arc of 1995 SN55) - 1 2 Sokol, Joshua (25 October 2017). "A 300-kilometre space rock has vanished since we saw it in 1995". New Scientist. Retrieved 24 February 2021.
- 1 2 Gibson, B.; Goggia, T.; Primak, N.; Schultz, A.; Willman, M.; Chambers, K.; et al. (17 July 2016). "MPEC 2016-O154 : 2014 OK394". Minor Planet Electronic Circular. 2016-O154. Minor Planet Center. Bibcode:2016MPEC....O..154G. Retrieved 23 February 2021.
- 1 2 "M.P.C. 111781" (PDF). Minor Planet Circular. Minor Planet Center. 25 September 2018. Retrieved 23 February 2021.
- ↑ Deen, Sam (30 November 2020). "1995 SN55". groups.io. Retrieved 23 February 2021.
- 1 2 "M.P.C. 127300" (PDF). Minor Planet Circular. Minor Planet Center. 27 January 2021. Retrieved 23 February 2021.
External links
[edit]
- A 300-kilometre space rock has vanished since we saw it in 1995, Joshua Sokol, New Scientist, 25 October 2017
- (523731) 2014 OK394 at the JPL Small-Body Database
