120347 Salacia

Possible dwarf planet yes 120347 Salacia 24px or 24px (rare) possible dwarf planet Salacia and Actaea Keck-NIRC2.jpg Keck Telescope image of Salacia (center) and its moon Actaea (left), taken by the NIRC2 near-infrared camera on 3 August 2010. H. G. RoeM. E. BrownK. M. Barkume Palomar Obs. 22 September 2004 25 July 1982 (120347) Salacia s ə ˈ l eɪ ʃ ə (sə LAY shə) Salacian Salacia (Roman mythology) 2004 SB 60 TNOclassical (hot)extended 31 May 2020 (JD 2459000.5) 3 37.16 yr (13,572 days) 46.670 AU 37.697 AU 42.184 AU 0.10636 273.98 yr (100,073 days) 123.138° 0.0035974 ms / day 23.921° 279.880° 312.294° 1 (Actaea) 838 44 km 4.861 0.076 0.074 20 kg (Total system mass) 1.45 ≈ g/cm3 (7 September 2025)assuming equal densities for the both objects 1.38 0.22 0.18 g/cm3 (2 September 2025)assuming equal densities for the both bodies, using the old size estimate of 866 37 km and 290 21 km for Salacia and Actaea respectively. 1.50 0.12 g/cm3 (2019) 5.49403 0.00016 d (synchronous) Prominent water (H 2 O-type)6 BB (neutral) B−V 0.66 0.06 V−R 0.40 0.04 0.041 0.004 (2025) 4.360 0.011 (Salacia+Actaea)4.476 0.013 (Salacia)4.15 20.7 120347 Salacia (provisional designation 2004 SB 60) is a large trans-Neptunian object in the Kuiper belt. It was discovered on 22 September 2004 by American astronomers Henry G. Roe, Michael E. Brown, and Kristina Barkume using the Hale Reflector at the Palomar Observatory. Its discovery was officially announced in May 2005. Salacia orbits the Sun at an average distance slightly greater than that of Pluto, and is classified as a hot cubewano or a scattered–extended object. It was named after the Roman sea goddess Salacia. Salacia is a possible dwarf planet with an estimated diameter of 838 44 km, and a low light curve, implying a nearly spherical shape. While older size estimates suggested a low density and highly porous interior, newer measurements calculate a higher density between 1.45 g/cm3 and 1.50 0.12 g/cm3. It has a dark gray surface with a neutral color index and an exceptionally low albedo of 0.041 0.004. This low albedo indicates a lack of geological activity. Observations by the James Webb Space Telescope (JWST) showed that water ice makes up less than 5% of its surface, detecting both amorphous and crystalline water ice alongside carbon dioxide ice. It lacks volatile super-ices like methane, placing it in the "prominent water" (H2O-type) TNO group alongside objects like 307261 Máni and 90482 Orcus.4 Salacia has one known moon, Actaea, and their combined system mass is 4.861 0.076 0.074 20 kg. The primary body and its moon form a fully tidally locked system with a synchronous rotation period of 5.49 days, similar to the Pluto–Charon system. The two bodies will pass directly in front of each other during a rare mutual occultation season starting in 2067. History Discovery thumb|upright|The dome of the Palomar Observatory in California, where Salacia was discovered on 22 September 2004. Salacia was discovered on 22 September 2004 by American astronomers Henry Roe, Michael Brown, and Kristina Barkume at the Palomar Observatory in California, United States. The discovery observations were formally published in May 2005 in the Minor Planet Electronic Circular (MPEC) 2005-J26. The object was announced alongside a group of seven new trans-Neptunian objects tracked by the IAU's Minor Planet Center. At the time of its initial detection on 22 September, Salacia was recorded with a red-filter apparent magnitude ranging between 20.1 and 20.6. Following its initial tracking, the object was assigned the provisional designation 2004 SB 60. While the discovery tracking occurred in 2004, astronomers successfully verified earlier positions of the body through archival precovery images taken at the Siding Spring Observatory (Station 260) dating back to 25 July 1982. Further observations The observation arc of Salacia begins with a precovery observation on 25 July 1982 at the Siding Spring Observatory (Station 260). Between 2001 and 2003, Salacia was pictured multiple times by the Near-Earth Asteroid Tracking (NEAT) program at Palomar (Station 644) and the Sloan Digital Sky Survey at Apache Point (Station 645). After its discovery in 2004, it was observed by the 5-meter Hale Reflector (Station 675) and the 3.5-meter telescope at Mauna Kea (Station 568). As of May 2026, a total of 490 observations have been recorded over a period of 37.16 years (13,572 days). These observations were made by ground-based and space-based telescopes, such as the Hubble Space Telescope (Station 250). More recent tracking was done by the Pan-STARRS 1 survey (Station F51), the Weizmann Astrophysical Observatory (Station M01), and the Pises Observatory (Station 122). The most recent observation recorded in the Minor Planet Center database was done on 1 November 2025, at F51 – Pan-STARRS 1, Haleakalā. Nomenclature Numbering and naming thumb|Salacia, the goddess of salt water This minor planet was named after Salacia (s ə ˈ l eɪ ʃ ə sə LAY shə, la saˈɫaːkia lang), the goddess of salt water, consort of Neptune. She is the Roman equivalent of the Greek sea goddess Amphitrite or Tethys. The object had been assigned its permanent minor planet number (120347) on 16 November 2005, following the precise consolidation of its orbital path data. The official naming citation was subsequently published on 18 February 2011 in M.P.C. 73984, which formally established the name within the International Astronomical Union's minor planet index. Its moon's name is called Actaea (æ k ˈ t iː ə; grc Ἀκταία Aktaía the dweller on coasts.Kerényi Carl The Gods of the Greeks Thames and Hudson 1951 London 64 It was from grc ἀκτή akté seashore or 'rocky shore') being one of the 50 Nereid sea-nymphs, matching the system's marine naming theme.Homer, Iliad 18.41; Apollodorus, 1.2.7; Hesiod, Theogony 240Bane Theresa Encyclopedia of Fairies in World Folklore and Mythology McFarland, Incorporated, Publishers 2013 978-0-7864-7111-9 11, 12 Planetary symbol thumb|Salacia's symbol Planetary symbols are no longer used much in astronomy, so Salacia never received a symbol in the astronomical literature. Denis Moskowitz, a software engineer who designed most of the dwarf planet symbols, proposed a stylised hippocamp (16px, formerly 16px) as the symbol for Salacia; although this symbol is not widely used. Orbit and classification Salacia orbits the Sun at a distance of 37.7–46.7 AU with a semi-major axis of 42.2 AU, finishing its orbit once every 274.0 years. Salacia is a non-resonant object with a moderate eccentricity of approximately 0.11 and a large inclination of 23.9° with respect to the ecliptic. The orbit of Salacia is similar to Pluto's, except for a near opposite longitude of ascending node. Its current position is near its most northern position above the ecliptic. Salacia is located in the classical region of the Kuiper belt between 39 and 48 AU from the Sun. Because it lacks an active orbital resonance with Neptune, it is grouped as a typical member of the classical Kuiper belt population, commonly called "cubewanos". However, Salacia's steep orbital inclination of 23.9° places it within the dynamically "hot" sub-population of the classical belt. Unlike cold classical objects that formed in place along circular paths, hot classical bodies likely formed closer to the Sun and were scattered outward into highly tilted orbits during the early migration of Neptune.230 Astronomers utilize different frameworks to sort these outer Solar System bodies, leading to a long-standing academic debate over Salacia's exact status. In the Deep Ecliptic Survey framework by Elliot et al., Salacia is grouped as a scattered–extended object because the system automatically places highly tilted orbits into the scattered categories. Conversely, Brett Gladman and his team reject this label based on a 10-million-year computer simulation testing orbital stability. Because Salacia's orbit stays perfectly stable and completely clear of Neptune's gravity during the simulation, Gladman et al. formally classify it as a hot classical Kuiper belt object. This orbital path also places it near the Haumea collisional family by coincidence; however, tracking and space-based spectral data confirm Salacia is an unrelated background object despite its water-ice rich surface. thumb|The orbit of Salacia compared to Pluto's and the eight planets' orbits in top view and the side view. Observability Occultations + Salacia stellar occultationsDateStar apparent magnitude (G-mag)OccultationdurationMeasured chordlengthTarget bodyObserving asset /Network27 Dec 201815.566.7 s (maximum duration)15px|MaybeSalaciaLESIA Lucky Star28 Jul 202315px|Maybe31.2 0.3 s786.5 7.8 kmSalaciaLa Silla 1.54m Telescope317 Aug 202415.948.2 s (maximum duration)15px|MaybeSalacia & ActaeaHubble / LESIA26 Jan 202713.942.5 s (predicted)15px|MaybeSalaciaSwRI RECON network Stellar occultations by Salacia happen when it passes in front of a background star, letting scientists measure its precise position, shape, and size profile.1 To make predictions more precise, astronomers map Salacia's orbit using wide-field star catalogs, while a 2015 study identified four potential occultations visible by the James Webb Space Telescope using faint background stars between infrared magnitudes 14 and 16. Several recorded campaigns have progressively narrowed Salacia's orbital path from an early uncertainty of about 2300 km. On 27 December 2018, an event monitored by the LESIA - Observatoire de Paris against a Gaia magnitude 15.5 star captured a 4.8 magnitude drop, significantly refining the orbit from an initial ground-based uncertainty of 4214.9 km. Following this, a 28 July 2023 occultation captured by the 1.54m Danish Telescope at La Silla recorded a light drop lasting 31.2 0.3 s at a relative speed of 25.24 km/s, providing a direct single-chord surface size measurement of 786.5 7.8 km.2–3 A rare double stellar occultation was recorded on 17 August 2024, when both Salacia and its moon, Actaea, blocked the same Gaia magnitude 15.9 star within 5 minutes of each other. Because the initial ground-based path carried a massive uncertainty of 1842.8 km, astronomers used the Hubble Space Telescope under Proposal 17848 to take precise photos beforehand, reducing the uncertainty to just 300 km.1–2 This allowed ground stations to align their telescopes perfectly, recording a sharp 5.0 magnitude drop to measure both bodies, while the RECON network is targeting a future occultation of a magnitude 13.9 star scheduled for 26 January 2027. Rotation and hypothesized shape Light curves and shape thumb|Salacia's light curve amplitude. Salacia has a very low light curve amplitude of only about 3%, meaning its brightness does not change much as it spins. Accurate tracking measures this variation at 0.0900 0.0036 magnitudes. This small change suggests that Salacia is either nearly a perfect sphere or its pole is pointing almost directly at Earth. In planetary science, minor light variations can be caused by either an elongated shape or by dark and light spots on a round body. An elongated shape would produce a double-peaked light curve with two minimums and maximums per rotation. Because Salacia's light variations show a single-peaked pattern with only one peak per cycle, astronomers explicitly reject the elongated triaxial ellipsoid shape idea. Instead, the light curve is entirely driven by uneven albedo variations across its surface, so Salacia is unlikely to be an elongated triaxial ellipsoid, but rather having a nearly spherical shape with small albedo variations across its surface. Rotational speed and mutual tidal locking In 2014, early studies estimated that Salacia rotated very fast, once every 6.09–6.5 hours. However, a long-term study published in 2025 showed this was a mathematical error called "observational aliasing." Because ground telescopes could only watch Salacia for a few days at a time, the gaps in the data made a slow 5.49-day spin look like a fast 6.5-hour cycle. The 2025 study analyzed 165 hours of data collected over 16 years. By combining ground tracking with images from the Hubble Space Telescope, scientists found that Salacia's 5.49-day rotation exactly matches the time its moon, Actaea, takes to complete one orbit (5.49389 0.00001 d). thumb|center|200px|The Pluto–Charon system — an example of mutual tidal locking, similar to the Salacia–Actaea system. This means the two bodies are mutually tidally locked in a "doubly synchronous rotation," always showing the exact same face to each other just like Pluto and Charon. Before this happened, Salacia likely spun much faster, at around 10 hours per rotation. Because Actaea is relatively large, its gravitational pull created internal friction that gradually slowed Salacia down. Computer models show this tidal slowing took only 150 million to 400 million years to finish, meaning the pair has been locked in this balance for billions of years. Separating the individual light data also revealed features about the moon itself. While Salacia shows small brightness changes, Actaea exhibits a very high light curve amplitude of at least 0.95 magnitudes. This indicates that Actaea either has a highly stretched shape or extreme surface contrasts with large dark and light patches. This discovery cements the system as only the third confirmed doubly synchronous binary in the trans-Neptunian region, joining Pluto–Charon and Eris–Dysnomia. Physical characteristics thumb|center|Comparison of sizes, albedos, and colors of various large trans-Neptunian objects with diameters greater than 700 km mi. Salacia is shown on the middle row, third from the right. The dark colored arcs represent uncertainties of the object's size. Size, mass and density May 2026 + History of diameter estimates for Salacia Year of Publication Diameter (km) Method References 2012 905 103 thermal (Spitzer) 2013 874 32 thermal (Herschel) 2013 854 45 thermal (Spitzer) 2017 866 37 dynamical (HST) 2019 846 21 thermal (combined) approximation if Salacia and Actaea were both spherical and had the same albedo 2025 838 44 thermal (ALMA/NEATM) In 2025, the total mass of the Salacia–Actaea system was estimated to be at 4.861 0.076 0.074 20 kg, with an average system density of 1.50 0.12 g/cm3 which was estimated in 2019; Salacia itself was estimated to be around 838 km in diameter, which is slightly smaller than Orcus (910 50 40 km). Salacia has the lowest albedo of any known large trans-Neptunian object, having an albedo of only 0.041 0.004. According to the old estimate from 2017 based on an improved thermophysical modelling, the size of Salacia is slightly larger at around 866 km and its density therefore is slightly lower, being calculated at only 1.26 g/cm3 with the old mass estimate of around 4.38 0.16 20 kg. At 838 44 km, Salacia belongs to the proposed class of "mid-sized" TNOs between 400 and 1,000 km (250 and 620 mi) in diameter. It represents the evolutionary transition between small, low-density TNOs and large, high-density dwarf planets. William Grundy and his team originally hypothesized that these mid-sized objects maintain highly porous and unheated interiors because structurally similar bodies like 55637 Uni and 229762 Gǃkúnǁʼhòmdímà exhibit low densities near 1 g/cm³. Under this framework, Grundy et al. proposed that low-albedo, mid-sized bodies did not undergo internal melting or differentiation like Orcus, Quaoar, and Charon. thumb|Salacia's density and albedo compared to the other most likely dwarf planets|300x300px Grundy et al. initially rejected Salacia as a dwarf planet due to its older, lower density estimates, describing Salacia as a "dwarf planet–sized TNO." However, just a few months later after they published the low density theory, they backed off that position when newer studies found that Salacia's density is relatively high, around 1.50 0.12 g/cm3, while kiss et al in 2025 yielded a density of 1.45 g/cm3 assuming equal densities for Salacia and Actaea. If these estimates are accurate, then Salacia would have a higher density than Orcus (1.4 0.2 g/cm3). Nonetheless, its extremely low albedo of 4.1% remains consistent with an ancient surface that lacks the widespread geological activity typical of larger dwarf planets. American astronomer Michael E. Brown considers Salacia nearly certain to be a dwarf planet, placing it at the lower edge of his "nearly certain" ranking tier. Surface and spectrum Salacia has a dark gray surface with an extremely low albedo of 0.041 0.004 that was measured by Kiss et al. in 2025, and a B-V color index of approximately 0.66 0.06, which is considered a neutral color. Salacia's infrared spectrum is complex. Earlier studies have detected an abundance of water ice of less than 5% on the surface. However, astronomers got a much clearer look at the surface on 31 August 2023 using the Near-Infrared Spectrograph (NIRSpec) on the James Webb Space Telescope.2 Observed under Guaranteed Time Observations program 1191, Salacia was at a heliocentric distance of 45.1 au and a phase angle of 0.94°.2 thumb|center|The near-infrared spectrum of Salacia as measured by the James Webb Space Telescope. The spectrum of Salacia suggests crystalline water ice on its surface.|600x600px The JWST spectrum showed distinct water-ice absorption bands at 1.5, 2, 3, and between 4–5 μm, with a very sharp drop right at 3 μm.1, 3 The specific diagnostic band for crystalline water ice at 1.65 μm is weak and difficult to verify.3 This indicates that Salacia's surface has a complex mix of both crystalline and amorphous water ice.3–4 The shape of the absorption features between 4.5–5.0 μm depends heavily on how these two ice phases are mixed and the size of their ice grains.4 Because water ice has a very high extinction coefficient at 3 μm, the absorption band at that wavelength is nearly 100% optically saturated.7 Minor variations in this saturated band suggest the ice sits in complex vertical layers or uneven mixtures in the upper crust.7 It also detected carbon dioxide ice through its strong ν3 fundamental vibrational band at 4.25 μm.1, 4 The spectrum displays a distinct V-shaped CO2 absorption feature that bottoms out at 4.27 μm.4, 8 This specific V-shape shows that the carbon dioxide ice is not a pure crystalline layer, but is likely trapped as an amorphous mixture inside the surrounding water ice.8 Data from the 2.6–2.8 μm range showed no signatures of hydrogen peroxide (H2O2), which space radiation usually creates on pure water ice.8 Astronomers also searched for a weaker absorption band at 4.37 μm from the heavier isotope 13CO2, but the data was too noisy to confirm it.4 Salacia completely lacks volatile super-ices like methane (CH4) or carbon monoxide (CO).1, 5 Its surface escape velocity is only 385 - 542 m/s, which is too weak to keep solar-heated volatile gases from escaping into space at local temperatures of 30–50 K.5 This low gravity explains why Salacia also lacks aliphatic hydrocarbons and complex organic signatures between 3.3–3.6 μm.5 However, because Salacia is larger than the critical geophysical threshold of roughly 500 km, it had enough early radiogenic heating to melt and move its internal water and carbon dioxide ices up to the surface.7 This internal evolution explains why Salacia keeps an ice-rich surface despite its low albedo and lack of ongoing cryovolcanism.7 Because of these strong water and carbon dioxide ice signatures and lack of complex organics, Salacia is classified as a "prominent water" (H2O-type) TNO under recent taxonomic frameworks.1, 4 Other mid to large trans-Neptunian objects such as 307261 Máni, 90482 Orcus and 208996 Achlys also have Salacia's neutral spectrum and has a water ice-rich surface or composition. These objects are all classified as "prominent water" (H 2 O)-type TNOs according to Wong.5–6 Binary system Moon Actaea (moon) thumb|250px|A simulated nearly circular orbit of Actaea at a distance of 5700 30 29 km away from Salacia. Salacia has one known moon, Actaea. It orbits Salacia every 5.49389 0.00016 d at a distance of 5700 30 29 km with an eccentricity of 0.008 0.003. It was discovered on 21 July 2006 by Keith Noll, Harold Levison, Denise Stephens and William Grundy with the Hubble Space Telescope. Actaea has a diameter of 393 33 km, making it the fifth-largest known moon of a trans-Neptunian object, after Charon (1212 1 km), Dysnomia (615 60 50 km),7 Vanth (442.5 10.2 km), and Ilmarë (403 40 km). Assuming that Actaea has a density of 0.7 g/cm3, which is thought to be typical that of trans-Neptunian objects' moons, The mass ratio between Actaea and Salacia will be approximately 0.044:1.This means Actaea is approximately 4.4% the mass of Salacia. It has an extremely low albedo of 0.021 0.004, which is only half the albedo of Salacia (0.041 0.004). Tidal evolution The Salacia system has undergone enough tidal evolution to circularize its orbit, which matches the low measured eccentricity. The ratio of Actaea's semi-major axis to its primary's Hill radius is 0.0023, making it the tightest out of every known trans-Neptunian binary with a calculated orbit. Tidal forces transferred angular momentum from Salacia's rotation directly into Actaea's orbit, forcing the moon to push farther away until the distance between the two bodies expanded to its modern value of about 13.2 Salacia radii. Tidal models show that if Salacia remained an unheated, mixed-up blend of primitive rock and ice, this evolution would have dragged out for nearly 1 billion years. However, the system could have synchronized much faster, in about 100 million years, if its interior separated early in its history through an ancient, brief epoch of internal melting. This allowed the system to reach its stable, quiet state early in the history of the Solar System, whereas larger, more massive bodies like Eris required nearly 4 billion years to complete their tidal cycles. Proposed explorations Salacia has not been visited by a space probe, though many studies have found it to be a feasible target for future missions. Planetary scientists advocate for the exploration of large trans-Neptunian objects to provide insights into the formation and evolution of the Solar System.5 Several studies have analyzed flyby trajectories to Salacia using planetary gravity assists to reduce flight time. A 2019 study by Amanda Zangari and her team showed that a spacecraft launched between 2025 and 2027 could use a single Saturn gravity assist to reach Salacia in 15.4 to 24.2 years, depending on the launch vehicle's power. For later windows, Samuel Walters and James Lyne identified a 2031 trajectory that utilizes an unpowered Jupiter gravity assist, allowing a probe to complete its outer Solar System transit in exactly 25 years and arrive at Salacia in February 2056.12 Advanced flight frameworks using an Earth and Jupiter gravity assist combination (ΔVEGA-JGA) have also been evaluated. A 2021 trajectory survey by James Evans Lyne and colleagues identified a launch window on 15 January 2029 with an 18.4-year transit time, and a second option on 27 February 2042 with an 18.2-year duration.2 Multi-target missions involving other outer planets have also been proposed. Bryan J. Holler and his team found a 2040 mission design that performs a close flyby of Neptune before reaching Salacia in December 2046. A separate dual-probe mission analyzed by Anderson et al. proposed launching an 800 kg Salacia flyby probe alongside a Neptune flagship mission on 28 February 2042.39 Under this optimized flight plan, the Salacia probe would use a Jupiter gravity assist to complete its transit in 17.6 years, executing its close flyby encounter in October 2059.39 Additionally, the feasibility of an orbital capture rendezvous has been studied, with a 2013 university assessment showing options for putting a 100 to 380 kg orbiter into a permanent orbit around Salacia using a Jupiter swingby. See also 307261 Máni, a dwarf planet candidate in the Kuiper belt that is similar to Salacia in size and composition with large topographic features 174567 Varda and its moon Ilmarë, a system with similar characteristics 208996 Achlys – another large, gray-colored Kuiper belt object with abundant water ice and an elongated shape like Haumea List of trans-Neptunian objects List of solar system objects by size List of possible dwarf planets Double planet List of minor planets: 120001–121000 Minor-planet moon Notes References 30em 2019-09-21 last obs. JPL Small-Body Database Browser: 120347 Salacia (2004 SB60) https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2120347 Jet Propulsion Laboratory 7 November 2019 20 February 2020 3 April 2017 https://web.archive.org/web/20170403194747/https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2120347 live (120347) Salacia = 2004 SB60 Minor Planet Center https://www.minorplanetcenter.net/db_search/show_object?object_id=120347 22 July 2018 3 April 2017 https://web.archive.org/web/20170403112159/http://www.minorplanetcenter.net/db_search/show_object?object_id=120347 live MPC/MPO/MPS Archive Minor Planet Center https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html 3 April 2017 11 September 2019 https://web.archive.org/web/20190911230626/https://www.minorplanetcenter.net/iau/ECS/MPCArchive/MPCArchive_TBL.html live S. Fornasier E. Lellouch T. Müller, P. etal TNOs are Cool: A survey of the trans-Neptunian region. VIII. Combined Herschel PACS and SPIRE observations of 9 bright targets at 70–500 μm Astronomy & Astrophysics 555 A92 10.1051/0004-6361/201321329 free 2013 1305.0449v2 2013A&A...555A..15F 119261700 Physical Properties of Trans-Neptunian Binaries (120347) Salacia–Actaea and (42355) Typhon–Echidna Icarus 219 676–688 J.A. Stansberry W.M. Grundy M. Mueller 2 etal 2012 10.1016/j.icarus.2012.03.029 2012Icar..219..676S Marc W. Buie Marc W. Buie 2007-08-12 using 62 of 73 observations Orbit Fit and Astrometric record for 120347 SwRI (Space Science Department) http://www.boulder.swri.edu/~buie/kbo/astrom/120347.html 2009-10-04 2012-03-09 https://web.archive.org/web/20120309113753/http://www.boulder.swri.edu/~buie/kbo/astrom/120347.html live 0808.0185 E. L. Schaller M. E. Brown Detection of Additional Members of the 2003 EL61 Collisional Family via Near-Infrared Spectroscopy Astrophysical Journal 684 2 L107–L109 2008 2008ApJ...684L.107S 10.1086/592232 118487075 http://www.cbat.eps.harvard.edu/iauc/08700/08751.html IAUC 8751: (120347) 2004 SB_60; 2006gi, 2006gj; V733 Cep Cbat.eps.Harvard.edu 2014-06-14 2013-12-03 https://web.archive.org/web/20131203012326/http://www.cbat.eps.harvard.edu/iauc/08700/08751.html live Gladman B. Marsden B. G. VanLaerhoven C. 2008 Nomenclature in the Outer Solar System http://www.lpi.usra.edu/books/ssbn2008/7002.pdf The Solar System Beyond Neptune 43 2016-05-01 2012-11-02 https://web.archive.org/web/20121102205338/http://www.lpi.usra.edu/books/ssbn2008/7002.pdf live Updated taxonomy of trans-neptunian objects and centaurs: Influence of albedo Irina N. Belskaya Maria A. Barucci Marcello Fulchignoni M. Lazzarin April 2015 Icarus 250 482–491 10.1016/j.icarus.2014.12.004 2015Icar..250..482B Mutual Orbit Orientations of Transneptunian Binaries http://www2.lowell.edu/~grundy/abstracts/preprints/2019.TNB_orbits.pdf W. M. Grundy K. S. Noll H. G. Roe M. W. Buie S. B. Porter A. H. Parker D. Nesvorný S. D. Benecchi D. C. Stephens C. A. Trujillo Icarus 334 62–78 2019 10.1016/j.icarus.2019.03.035 2019Icar..334...62G 133585837 0019-1035 2019-10-26 https://web.archive.org/web/20200115091416/http://www2.lowell.edu/~grundy/abstracts/preprints/2019.TNB_orbits.pdf 2020-01-15 Brown Michael E. Butler Bryan J. The Density of Mid-sized Kuiper Belt Objects from ALMA Thermal Observations The Astronomical Journal 20 June 2017 154 1 19 10.3847/1538-3881/aa6346 1702.07414 2017AJ....154...19B free etal J. C. Cook R. Brunetto A. C. De Souza Feliciano J. Emery B. Holler A. H. Parker Hapke Modeling of Several KBOs from JWST Observations https://www.hou.usra.edu/meetings/acm2023/pdf/2526.pdf Asteroids, Comets, Meteors Conference 2023 Lunar and Planetary Institute 2851 June 2023 2023-05-24 2023-05-24 https://web.archive.org/web/20230524001156/https://www.hou.usra.edu/meetings/acm2023/pdf/2526.pdf live etal Ian Wong Bryan J. Holler Silvia Protopapa Aurélie Guilbert-Lepoutre William M. Grundy John A. Stansberry JWST/NIRSpec Observations of Salacia-Actaea and Máni: Exploring Population-level Trends among Water-ice-rich Kuiper Belt Objects The Planetary Science Journal December 2025 6 12 281 free 10.3847/PSJ/ae1d63 2508.17101 2025PSJ.....6..281W Collyer Cameron Fernandez-Valenzuela Estela Jose Luis Ortiz Holler Bryan J. Proudfoot Benjamin Morales Nicolas Morales Rafael Benecchi Susan Rommel Flavia L. Grundy Will Ragozzine Darin Synchronous Rotation in the (120347) Salacia-Actaea System The Planetary Science Journal 2025 6 11 270 10.3847/PSJ/ae0b6a free 2509.02734 2025PSJ.....6..270C W. M. Grundy K. S. Noll M. W. Buie S. D. Benecchi D. Ragozzine H. G. Roe The Mutual Orbit, Mass, and Density of Transneptunian Binary Gǃkúnǁʼhòmdímà ((229762) 2007 UK 126) http://www2.lowell.edu/users/grundy/abstracts/preprints/2019.G-G.pdf Icarus December 2019 334 30–38 10.1016/j.icarus.2018.12.037 2019Icar..334...30G 126574999 2019-04-07 2026-04-07 https://web.archive.org/web/20190407045339/http://www2.lowell.edu/~grundy/abstracts/preprints/2019.G-G.pdf dead Patryk Sofia Lykawka Mukai Tadashi Dynamical classification of trans-neptunian objects: Probing their origin, evolution, and interrelation Icarus July 2007 189 1 213–232 10.1016/j.icarus.2007.01.001 2007Icar..189..213L 122671996 etal Csaba Kiss Krisztina Gabányi Attila Moór Thomas Müller Estela Fernandez-Valenzuela Arielle Moullet ALMA submm measurements of the trans-Neptunian binary system satellites Ilmarë, Actaea, Hi'iaka and Namaka https://meetingorganizer.copernicus.org/EPSC-DPS2025/EPSC-DPS2025-905.html EPSC-DPS Joint Meeting 2025 September 2025 18 EPSC-DPS2025-905 free 10.5194/epsc-dps2025-905 Fornasier S. Lellouch E. Müller T. Santos-Sanz P. Panuzzo P. Kiss C. Lim T. Mommert M. Vilenius E. etal July 2013 TNOs are Cool: A survey of the trans-Neptunian region. VIII. Combined Herschel PACS and SPIRE observations of nine bright targets at 70–500 μm https://www.aanda.org/articles/aa/full_html/2013/07/aa21329-13/aa21329-13.html Astronomy & Astrophysics 555 A15 10.1051/0004-6361/201321329 free 2013A&A...555A..15F 2026-05-06 Physical Properties of Trans-Neptunian Binaries (120347) Salacia–Actaea and (42355) Typhon–Echidna Elsevier J.A. Stansberry Icarus 2012 219 2 676–688 10.1016/j.icarus.2012.03.029 2012Icar..219..676S http://www.sciencedirect.com/science/article/pii/S0019103512001224 2012-04-27 subscription Johnston Wm. Robert (120347) Salacia and Actaea https://www.johnstonsarchive.net/astro/astmoons/am-120347.html Johnston's Archive 2026-05-10 2026-05-10 MPEC 2005-J26: SEVEN TNOS https://www.minorplanetcenter.net/mpec/K05/K05J26.html Minor Planet Center 2026-05-10 2026-05-10 A. Thirouin K. S. Noll J. L. Ortiz N. Morales Rotational properties of the binary and non-binary populations in the Trans-Neptunian belt Astronomy & Astrophysics September 2014 569 A3 free 10.1051/0004-6361/201423567 1407.1214 2014A&A...569A...3T 119244456 Gurney Hudson 2008 The Works of Apuleius, Comprising the Metamorphoses, Or Golden Ass, the God of Socrates, the Florida, and His Defence, Or a Discourse on Magic READ BOOKS Manual of Mythology: for the use of schools, art students, and general readers founded on the works of Petiscus, Preller, and Welcker, Murray, A. S., Asher: 1873, Original from Oxford University, Digitized 19 Jan 2007 Varro, De lingua Latina, v. 72, "Salacia Neptuni a salo." Augustine, De civitate Dei, vii. 22, "Jam utique habebat Salaciam Neptunus uxoreum"; Servicius, on Virgil, Aen, x. 76, "Sane hane Veniliam quidam Salaciam accipiunt, Neptuni uxorem." Adonis Attis Osiris: Studies in the History of Oriental Religion, Frazer, J. G., Edition: 3, Kessinger Publishing: 2003 A Dictionary of Greek and Roman biography and mythology, Salacia https://www.unicode.org/L2/L2021/21224-dwarf-planet-syms.pdf Unicode request for dwarf-planet symbols Miller Kirk 26 October 2021 unicode.org 18 October 2022 23 March 2022 https://web.archive.org/web/20220323174107/https://www.unicode.org/L2/L2021/21224-dwarf-planet-syms.pdf live https://www.unicode.org/L2/L2024/24235-constellation-symbols.pdf Preliminary presentation of constellation symbols Miller Kirk 18 October 2024 unicode.org The Unicode Consortium 22 October 2024 The Pluto system: Initial results from its exploration by New Horizons S.A. Stern F. Bagenal K. Ennico G.R. Gladstone W.M. Grundy W.B. McKinnon J.M. Moore C.B. Olkin J.R. Spencer Science October 16, 2015 26472913 aad1815 350 6258 10.1126/science.aad1815 1510.07704 2015Sci...350.1815S 1220226 Brown Michael E. Butler Bryan J. Masses and Densities of Dwarf Planet Satellites Measured with ALMA The Planetary Science Journal 1 October 2023 4 10 193 10.3847/PSJ/ace52a free 2307.04848 2023PSJ.....4..193B Sickafoose A. A. Bosh A. S. Levine S. E. Zuluaga C. A. Genade A. Schindler K. Lister T. A. Person M. J. A stellar occultation by Vanth, a satellite of (90482) Orcus Icarus 1 February 2019 319 657–668 10.1016/j.icarus.2018.10.016 1810.08977 2019Icar..319..657S 119099266 Amanda M. Zangari Tiffany J. Finley S. Alan Stern Mark B. Tapley Return to the Kuiper Belt: Launch Opportunities from 2025 to 2040 Journal of Spacecraft and Rockets May 2019 56 3 919–930 10.2514/1.A34329 1810.07811 2019JSpRo..56..919Z 119033012 etal Bryan Holler Michele Bannister Kelsi Singer S. Alan Stern Susan Benecchi Cristina Ore Prospects for Future Exploration of the Trans-Neptunian Region https://hal.science/hal-03400878/document Planetary Science and Astrobiology Decadal Survey 2023-2032 Bulletin of the American Astronomical Society May 2021 53 4 228 10.3847/25c2cfeb.5950ca1c free 2021BAAS...53d.228H Jordan Kreitzman Ethan Cansler Charles W. Stewart Ethan Cansler Jake Brisby Matthew Green James Evans Lyne Mission Opportunities to Trans-Neptunian Objects—Part III, Orbital Capture, Low-Thrust Trajectories and Vehicle Radiation Environment During Jovian Flyby https://www.researchgate.net/publication/293081475 2024 AAS/AIAA Astrodynamics Specialist Conference Denver, Colorado 2013 AAS 13-802 1487–1506 2025-10-19 Anderson Canaan August 2025 INVESTIGATION AND OPTIMIZING OF INTERPLANATARY TRAJECTORIES TO TRANS-NEPTUNIAN OBJECTS Master's Thesis University of Tennessee, Knoxville https://www.researchgate.net/publication/394483553 Walters Samuel Lyne James E. A Survey of Mission Opportunities to Trans-Neptunian Objects, Part VI: A Search for Multi-Target Missions AIAA Propulsion and Energy 2020 Forum 2020 10.2514/6.2020-3831 https://www.researchgate.net/publication/344409907 Lyne James Evans Gleaves Ashley Quigley John Yousef Nicholas A Survey of Mission Opportunities to Trans-Neptunian Objects - Part 7: Utilization of a Delta V Earth Gravity Assist AAS/AIAA Astrodynamics Specialist Conference August 2021 https://www.researchgate.net/publication/355582324 Attwood Ben Performing Automated, High-Speed Photometry on Occulting, Small Outer Solar System Objects Edinburgh Student Journal of Science July 2024 https://www.medanthrotheory.org/esjs/article/download/9682/12433 Camargo J. I. B. Vieira Martins R. Assafin M. Braga-Ribas F. Sicardy B. Gomes-Júnior A. R. Dias-Pinto A. Candidate stars for stellar occultations by Neptunian Trojans and TNOs up to 2015 Astronomy & Astrophysics January 2014 561 A37 10.1051/0004-6361/201322584 free http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/561/A37 1401.4905 Occultation by Salacia (2018-12-27) https://lesia.obspm.fr/lucky-star/single.php?p=3352 LESIA - Observatoire de Paris Lucky Star Project 2018-12-27 Occultation by Salacia (2024-08-17) https://lesia.obspm.fr/lucky-star/occ.php?p=131439 LESIA - Observatoire de Paris Lucky Star Project 2024-08-17 Proudfoot Benjamin Parker Alex H. Grundy William M. Noll Keith S. Porter Simon B. 17848 - Astrometry for an Upcoming Double Occultation of Salacia-Actaea https://www.stsci.edu/hst-program-info/download/hst/pdf/17848/ Space Telescope Science Institute Hubble Space Telescope Observation Programs July 19, 2024 Buie Marc W. Keller John M. Nesvorný David Porter Simon B. Occultation constraints on solar system formation models Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences January 2025 383 2291 20240194 10.1098/rsta.2024.0194 https://royalsocietypublishing.org/rsta/article/383/2291/20240194/108397/Occultation-constraints-on-solar-system-formation 11866602 Santos-Sanz P. Ortiz J. L. Sicardy B. Stellar Occultations by Trans-Neptunian Objects From Ground and Space Gaya and TNOs Exploration Workshops https://www.cosmos.esa.int/documents/739790/758041/Santos-Sanz_modified.pdf/82dc16ea-0bf3-4314-a888-d46b67c4e710 European Space Agency Buie Marc W. RECON Occultation Details for (120347) Salacia on 2027 January 26 https://www2.boulder.swri.edu/~buie/recon/events/120347_270126_2141514.html Southwest Research Institute Astronomy Portal 2027-01-26 How many dwarf planets are there in the outer solar system? http://web.gps.caltech.edu/~mbrown/dps.html California Institute of Technology Brown Michael E. Michael E. Brown 13 September 2019 5 November 2019 Brown Michael E. Butler Bryan J. Medium-sized satellites of large Kuiper belt objects The Astronomical Journal 156 4 164 22 January 2018 1801.07221 10.3847/1538-3881/aad9f2 2018AJ....156..164B 119343798 free External links (120347) Salacia at Johnston's Archive Salacia: As big as Ceres, but much farther away (Emily Lakdawalla – 2012/06/26) 120347 (120346) 2004 RG319 120347 (120348) 2004 TY364 120347 120347 Category:Discoveries by Michael E. Brown Category:Named minor planets Category:Binary trans-Neptunian objects 20040922 Category:Named TNOs