884 Priamus

884 Priamus /ˈpraɪ.əməs/ is a large Jupiter trojan from the Trojan camp, approximately 110 kilometers (68 miles) in diameter. It was discovered on 22 September 1917, by German astronomer Max Wolf at Heidelberg Observatory in southern Germany.^[1] The dark D-type asteroid is one of the 20 largest Jupiter trojans and has a rotation period of 6.9 hours.^[5] It was named after the Trojan king Priam from Greek mythology.^[3]

884 Priamus

Discovery[1]
Discovered by	M. F. Wolf
Discovery site	Heidelberg Obs.
Discovery date	22 September 1917
Designations
MPC designation	(884) Priamus
Pronunciation	/ˈpraɪ.əməs/[2]
Named after	Priam (Greek mythology)[3]
Alternative designations	1917 CQ · 1929 XX 1938 KE
Minor planet category	Jupiter trojan[1][4][5] Trojan[6][7] · background[7]
Adjectives	Priamean
Orbital characteristics[4]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc	100.54 yr (36,722 d)
Aphelion	5.8147 AU
Perihelion	4.5487 AU
Semi-major axis	5.1817 AU
Eccentricity	0.1222
Orbital period (sidereal)	11.80 yr (4,308 d)
Mean anomaly	257.84°
Mean motion	0° 5m 0.96s / day
Inclination	8.9150°
Longitude of ascending node	301.56°
Argument of perihelion	335.46°
Jupiter MOID	0.4171 AU
TJupiter	2.9610
Physical characteristics
Mean diameter	101.09±0.54 km[8] 119.99±2.13 km[9]
Synodic rotation period	6.8605±0.0005 h[10]
Geometric albedo	0.037±0.001[9] 0.044±0.002[8]
Spectral type	D (Tholen)[11] D (Pan-STARRS)[5][12] U–B = 0.229±051[11] B–V = 0.750±0.050[13] V–R = 0.450±0.030[13] V–I = 0.900±0.017[5]
Absolute magnitude (H)	8.81[1][4][5][9] 8.98[8]

Orbit and classification

Priamus is orbiting in the trailing Trojan camp, at Jupiter's L₅ Lagrangian point, 60° behind its orbit in a 1:1 resonance (also see Trojans in astronomy). It is also a non-family asteroid of the Jovian background population.^[7]

It orbits the Sun at a distance of 4.5–5.8 AU once every 11 years and 10 months (4,308 days; semi-major axis of 5.18 AU). Its orbit has an eccentricity of 0.12 and an inclination of 9° with respect to the ecliptic.^[4] The body's observation arc begins at Heidelberg in November 1917, two months after its official discovery observation.^[1]

Naming

This minor planet was named from Greek mythology after Priam (Priamus; Priamos), the king of Troy during the Trojan War. The Jupiter trojans 624 Hektor and 3317 Paris are named after his sons Paris and Hector. The official naming of Ajax was first cited in The Names of the Minor Planets by Paul Herget in 1955 (H 86).^[3]

Physical characteristics

In the Tholen taxonomy, Priamus is a dark D-type asteroid, the most common spectral type among the Jupiter trojans, with few dozens already identified in the early Tholen and SMASS classification (Bus–Binzel).^[14] Priamus has also been characterized as a D-type by Pan-STARRS' survey.^[5][12]

Rotation period

Several rotational lightcurves have been obtained from photometric observations since the 1980s, when Priamus was first observed by William Hartmann (1988) and Stefano Mottola (1993). The best rated result from July 2010, by Robert Stephens at GMARS (G79) and Linda French at Illinois Wesleyan University using the 0.9-meter SMARTS telescope at CTIO in Chile, gave a well-defined rotation period of 6.8605±0.0005 hours with a consolidated brightness variation between 0.23 and 0.40 in magnitude (U=3).^[5][10]

In January 1993 and October 2001, two lightcurves were obtained by Stefano Mottola in collaboration with Claes-Ingvar Lagerkvist and Marco Delbo at Kvistaberg and Pino Torinese observatories, respectively (U=3/2+).^[15] Another measurement was made by Ukrainian astronomers in August 2010 (U=3).^[16]

Between January 2015, and December 2016, photometric observations by Robert Stephens and Daniel Coley in collaboration with Brian Warner at the Center for Solar System Studies, California, gave a three concurring periods of 6.854, 6.863 and 6.865 hours (U=3/3/3).^{[17][18][19][a]}

Diameter and albedo

According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Priamus measures 101.09 and 119.99 kilometers in diameter and its surface has an albedo of 0.044 and 0.037, respectively.^[8][9] The Collaborative Asteroid Lightcurve Link assumes a standard albedo for a carbonaceous asteroid of 0.057 and calculates a diameter of 96.29 kilometers based on an absolute magnitude of 8.81.^[5]

Largest Jupiter Trojans by survey(A) (mean-diameter in kilometers; YoD: Year of Discovery)
Designation	H	WISE	IRAS	Akari	Ln	RP	V–I	YoD	Ref
624 Hektor	7.2	225	233	230.99	L4	6.92	0.930	1907	list
617 Patroclus	8.19	140.362	140.92	140.85	L5	102.80	0.830	1906	list
911 Agamemnon	7.89	131.038	166.66	185.30	L4	6.59	0.980	1919	list
588 Achilles	8.67	130.099	135.47	133.22	L4	7.31	0.940	1906	list
3451 Mentor	8.4	126.288	116.30	117.91	L5	7.70	0.770	1984	list
3317 Paris	8.3	118.790	116.26	120.45	L5	7.09	0.950	1984	list
1867 Deiphobus	8.3	118.220	122.67	131.31	L5	58.66	0.930	1971	list
1172 Äneas	8.33	118.020	142.82	148.66	L5	8.71	0.950	1930	list
1437 Diomedes	8.3	117.786	164.31	172.60	L4	24.49	0.810	1937	list
1143 Odysseus	7.93	114.624	125.64	130.81	L4	10.11	0.860	1930	list
2241 Alcathous	8.64	113.682	114.63	118.87	L5	7.69	0.940	1979	list
659 Nestor	8.99	112.320	108.87	107.06	L4	15.98	0.790	1908	list
3793 Leonteus	8.7	112.046	86.26	87.58	L4	5.62	0.780	1985	list
3063 Makhaon	8.4	111.655	116.14	114.34	L4	8.64	0.830	1983	list
1583 Antilochus	8.6	108.842	101.62	111.69	L4	31.54	0.950	1950	list
884 Priamus	8.81	101.093	96.29	119.99	L5	6.86	0.900	1917	list
1208 Troilus	8.99	100.477	103.34	111.36	L5	56.17	0.740	1931	list
1173 Anchises	8.89	99.549	126.27	120.49	L5	11.60	0.780	1930	list
2207 Antenor	8.89	97.658	85.11	91.32	L5	7.97	0.950	1977	list
2363 Cebriones	9.11	95.976	81.84	84.61	L5	20.05	0.910	1977	list
4063 Euforbo	8.7	95.619	102.46	106.38	L4	8.85	0.950	1989	list
2357 Phereclos	8.94	94.625	94.90	98.45	L5	14.39	0.960	1981	list
4709 Ennomos	8.5	91.433	80.85	80.03	L5	12.28	0.690	1988	list
2797 Teucer	8.7	89.430	111.14	113.99	L4	10.15	0.920	1981	list
2920 Automedon	8.8	88.574	111.01	113.11	L4	10.21	0.950	1981	list
15436 Dexius	9.1	87.646	85.71	78.63	L4	8.97	0.870	1998	list
3596 Meriones	9.2	87.380	75.09	73.28	L4	12.96	0.830	1985	list
2893 Peiroos	9.23	86.884	87.46	86.76	L5	8.96	0.950	1975	list
4086 Podalirius	9.1	85.495	86.89	85.98	L4	10.43	0.870	1985	list
4060 Deipylos	9.3	84.043	79.21	86.79	L4	9.30	0.760	1987	list
1404 Ajax	9.3	83.990	81.69	96.34	L4	29.38	0.960	1936	list
4348 Poulydamas	9.5	82.032	70.08	87.51	L5	9.91	0.840	1988	list
5144 Achates	9.0	80.958	91.91	89.85	L5	5.96	0.920	1991	list
4833 Meges	8.9	80.165	87.33	89.39	L4	14.25	0.940	1989	list
2223 Sarpedon	9.41	77.480	94.63	108.21	L5	22.74	0.880	1977	list
4489 Dracius	9.0	76.595	92.93	95.02	L4	12.58	0.950	1988	list
2260 Neoptolemus	9.31	76.435	71.65	81.28	L4	8.18	0.950	1975	list
5254 Ulysses	9.2	76.147	78.34	80.00	L4	28.72	0.970	1986	list
3708 Socus	9.3	75.661	79.59	76.75	L5	6.55	0.980	1974	list
2674 Pandarus	9.1	74.267	98.10	101.72	L5	8.48	1.000	1982	list
3564 Talthybius	9.4	73.730	68.92	74.11	L4	40.59	0.900	1985	list
4834 Thoas	9.1	72.331	86.82	96.21	L4	18.19	0.950	1989	list
7641 Cteatus	9.4	71.839	68.97	75.28	L4	27.77	0.980	1986	list
3540 Protesilaos	9.3	70.225	76.84	87.66	L4	8.95	0.940	1973	list
11395 Iphinous	9.8	68.977	64.71	67.78	L4	17.38	–	1998	list
4035 Thestor	9.6	68.733	68.23	66.99	L4	13.47	0.970	1986	list
5264 Telephus	9.4	68.472	73.26	81.38	L4	9.53	0.970	1991	list
1868 Thersites	9.5	68.163	70.08	78.89	L4	10.48	0.960	1960	list
9799 Thronium	9.6	68.033	64.87	72.42	L4	21.52	0.910	1996	list
4068 Menestheus	9.5	67.625	62.37	68.46	L4	14.40	0.950	1973	list
23135 Pheidas	9.9	66.230	58.29	68.50	L4	8.69	0.860	2000	list
2456 Palamedes	9.3	65.916	91.66	99.60	L4	7.24	0.920	1966	list
3709 Polypoites	9.1	65.297	99.09	85.23	L4	10.04	1.000	1985	list
1749 Telamon	9.5	64.898	81.06	69.14	L4	16.98	0.970	1949	list
3548 Eurybates	9.6	63.885	72.14	68.40	L4	8.71	0.730	1973	list
4543 Phoinix	9.7	63.836	62.79	69.54	L4	38.87	1.200	1989	list
12444 Prothoon	9.8	63.835	64.31	62.41	L5	15.82	–	1996	list
4836 Medon	9.5	63.277	67.73	78.70	L4	9.82	0.920	1989	list
16070 Charops	9.7	63.191	64.13	68.98	L5	20.24	0.960	1999	list
15440 Eioneus	9.6	62.519	66.48	71.88	L4	21.43	0.970	1998	list
4715 Medesicaste	9.7	62.097	63.91	65.93	L5	8.81	0.850	1989	list
34746 Thoon	9.8	61.684	60.51	63.63	L5	19.63	0.950	2001	list
38050 Bias	9.8	61.603	61.04	50.44	L4	18.85	0.990	1998	list
5130 Ilioneus	9.7	60.711	59.40	52.49	L5	14.77	0.960	1989	list
5027 Androgeos	9.6	59.786	57.86	n.a.	L4	11.38	0.910	1988	list
6090 Aulis	9.4	59.568	74.53	81.92	L4	18.48	0.980	1989	list
5648 Axius	9.7	59.295	63.91	n.a.	L5	37.56	0.900	1990	list
7119 Hiera	9.7	59.150	76.40	77.29	L4	400	0.950	1989	list
4805 Asteropaios	10.0	57.647	53.16	43.44	L5	12.37	–	1990	list
16974 Iphthime	9.8	57.341	55.43	57.15	L4	78.9	0.960	1998	list
4867 Polites	9.8	57.251	58.29	64.29	L5	11.24	1.010	1989	list
2895 Memnon	10.0	56.706	55.67	n.a.	L5	7.50	0.710	1981	list
4708 Polydoros	9.9	54.964	55.67	n.a.	L5	7.52	0.960	1988	list
(21601) 1998 XO89	10.0	54.909	55.67	56.08	L4	12.65	0.970	1998	list
12929 Periboea	9.9	54.077	61.04	55.34	L5	9.27	0.880	1999	list
17492 Hippasos	10.0	53.975	55.67	n.a.	L5	17.75	–	1991	list
5652 Amphimachus	10.1	53.921	53.16	52.48	L4	8.37	1.050	1992	list
2759 Idomeneus	9.9	53.676	61.01	52.55	L4	32.38	0.910	1980	list
5258 Rhoeo	10.2	53.275	50.77	n.a.	L4	19.85	1.010	1989	list
(12126) 1999 RM11	10.1	53.202	n.a.	n.a.	L5	n.a.	?	1999	list
(15502) 1999 NV27	10.0	53.100	55.67	50.86	L5	15.13	0.875	1999	list
4754 Panthoos	10.0	53.025	53.15	56.96	L5	27.68	–	1977	list
4832 Palinurus	10.0	52.058	53.16	n.a.	L5	5.32	1.000	1988	list
5126 Achaemenides	10.5	51.922	44.22	48.57	L4	53.02	–	1989	list
3240 Laocoon	10.2	51.695	50.77	n.a.	L5	11.31	0.880	1978	list
4902 Thessandrus	9.8	51.263	61.04	71.79	L4	738	0.960	1989	list
11552 Boucolion	10.1	51.136	53.16	53.91	L5	32.44	–	1993	list
(20729) 1999 XS143	10.4	50.961	46.30	n.a.	L4	5.72	1.000	1999	list
6545 Leitus	10.1	50.951	53.16	n.a.	L4	16.26	0.910	1986	list
4792 Lykaon	10.1	50.870	53.16	n.a.	L5	40.09	0.960	1988	list
21900 Orus	10.0	50.810	55.67	53.87	L4	13.45	0.950	1999	list
1873 Agenor	10.1	50.799	53.76	54.38	L5	20.60	–	1971	list
5028 Halaesus	10.2	50.770	50.77	n.a.	L4	24.94	0.900	1988	list
2146 Stentor	9.9	50.755	58.29	n.a.	L4	16.40	–	1976	list
4722 Agelaos	10.0	50.378	53.16	59.47	L5	18.44	0.910	1977	list
5284 Orsilocus	10.1	50.159	53.16	n.a.	L4	10.31	0.970	1989	list
11509 Thersilochos	10.1	49.960	53.16	56.23	L5	17.37	–	1990	list
5285 Krethon	10.1	49.606	58.53	52.61	L4	12.04	1.090	1989	list
4791 Iphidamas	10.1	49.528	57.85	59.96	L5	9.70	1.030	1988	list
9023 Mnesthus	10.1	49.151	50.77	60.80	L5	30.66	–	1988	list
5283 Pyrrhus	9.7	48.356	64.58	69.93	L4	7.32	0.950	1989	list
4946 Askalaphus	10.2	48.209	52.71	66.10	L4	22.73	0.940	1988	list
(22149) 2000 WD49	10.2	48.190	50.77	50.37	L4	7.84	1.090	2000	list
(32496) 2000 WX182	10.2	48.017	50.77	51.63	L5	23.34	0.950	2000	list
5120 Bitias	10.2	47.987	50.77	n.a.	L5	15.21	0.780	1988	list
12714 Alkimos	10.1	47.819	61.04	54.62	L4	28.48	–	1991	list
7352 Hypsenor	9.9	47.731	55.67	47.07	L5	648	0.850	1994	list
1870 Glaukos	10.6	47.649	42.23	n.a.	L5	5.99	—	1971	list
4138 Kalchas	10.1	46.462	53.16	61.04	L4	29.2	0.810	1973	list
(23958) 1998 VD30	10.2	46.001	50.77	47.91	L4	562	0.990	1998	list
4828 Misenus	10.4	45.954	46.30	43.22	L5	12.87	0.920	1988	list
4057 Demophon	10.1	45.683	53.16	n.a.	L4	29.82	1.060	1985	list
4501 Eurypylos	10.4	45.524	46.30	n.a.	L4	6.05	–	1989	list
4007 Euryalos	10.3	45.515	48.48	53.89	L4	6.39	–	1973	list
5259 Epeigeus	10.3	44.741	42.59	44.42	L4	18.42	–	1989	list
30705 Idaios	10.4	44.546	46.30	n.a.	L5	15.74	–	1977	list
16560 Daitor	10.7	43.861	51.42	43.38	L5	–	–	1991	list
(15977) 1998 MA11	10.4	43.530	46.30	51.53	L5	250	0.906	1998	list
7543 Prylis	10.6	42.893	42.23	n.a.	L4	17.80	–	1973	list
4827 Dares	10.5	42.770	44.22	n.a.	L5	19.00	–	1988	list
1647 Menelaus	10.5	42.716	44.22	n.a.	L4	17.74	0.866	1957	list
(A) Used sources: WISE/NEOWISE catalog (NEOWISE_DIAM_V1 PDS, Grav, 2012); IRAS data (SIMPS v.6 catalog); and Akari catalog (Usui, 2011); RP: rotation period and V–I (color index) taken from the LCDB Note: missing data was completed with figures from the JPL SBDB (query) and from the LCDB (query form) for the WISE/NEOWISE and SIMPS catalogs, respectively. These figures are given in italics. Also, listing is incomplete above #100.

100+ largest Jupiter trojans

Notes

1. Lightcurve plots of (884) Priamus from Jan 2015, Jan 2016 and Dec 2016 by Daniel Coley and Robert Stephens at the Center for Solar System Studies (U80) and (U81). Quality code is 3/3/3 (lightcurve rating at CS3). Summary figures at the LCDB and CS3.

References

1. "884 Priamus (1917 CQ)". Minor Planet Center. Retrieved 13 June 2018.
2. Noah Webster (1884) A Practical Dictionary of the English Language
3. Schmadel, Lutz D. (2007). "(884) Priamus". Dictionary of Minor Planet Names. Springer Berlin Heidelberg. p. 80. doi:10.1007/978-3-540-29925-7_885. ISBN 978-3-540-00238-3.
4. "JPL Small-Body Database Browser: 884 Priamus (1917 CQ)" (2018-05-24 last obs.). Jet Propulsion Laboratory. Retrieved 13 June 2018.
5. "LCDB Data for (884) Priamus". Asteroid Lightcurve Database (LCDB). Retrieved 18 August 2016.
6. "List of Jupiter Trojans". Minor Planet Center. 30 May 2018. Retrieved 13 June 2018.
7. "Asteroid (884) Priamus – Proper elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 13 June 2018.
8. Grav, T.; Mainzer, A. K.; Bauer, J. M.; Masiero, J. R.; Nugent, C. R. (November 2012). "WISE/NEOWISE Observations of the Jovian Trojan Population: Taxonomy". The Astrophysical Journal. 759 (1): 10. arXiv:1209.1549. Bibcode:2012ApJ...759...49G. doi:10.1088/0004-637X/759/1/49. S2CID 119101711. (online catalog)
9. Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan. 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. (online, AcuA catalog p. 153)
10. French, Linda M.; Stephens, Robert D.; Lederer, Susan M.; Rohl, Derrick A. (January 2011). "The Lightcurve of Jovian Trojan Asteroid 884 Priamus". The Minor Planet Bulletin. 38 (1): 2–3. Bibcode:2011MPBu...38....2F. ISSN 1052-8091. Retrieved 13 June 2018.
11. "Asteroid 884 Priamus". Small Bodies Data Ferret. Retrieved 13 June 2018.
12. Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. S2CID 53493339.
13. Chatelain, Joseph P.; Henry, Todd J.; French, Linda M.; Winters, Jennifer G.; Trilling, David E. (June 2016). "Photometric colors of the brightest members of the Jupiter L5 Trojan cloud". Icarus. 271: 158–169. Bibcode:2016Icar..271..158C. doi:10.1016/j.icarus.2016.01.026.
14. "JPL Small-Body Database Search Engine: [ spec. type = D (Tholen) or type = D (SMASSII) ]". JPL Solar System Dynamics. Retrieved 18 August 2016.
15. Mottola, Stefano; Di Martino, Mario; Erikson, Anders; Gonano-Beurer, Maria; Carbognani, Albino; Carsenty, Uri; et al. (May 2011). "Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects". The Astronomical Journal. 141 (5): 32. Bibcode:2011AJ....141..170M. doi:10.1088/0004-6256/141/5/170.
16. Shevchenko, V. G.; Belskaya, I. N.; Slyusarev, I. G.; Krugly, Yu. N.; Chiorny, V. G.; Gaftonyuk, N. M.; et al. (January 2012). "Opposition effect of Trojan asteroids". Icarus. 217 (1): 202–208. Bibcode:2012Icar..217..202S. doi:10.1016/j.icarus.2011.11.001. Retrieved 13 June 2018.
17. Stephens, Robert D.; Coley, Daniel R.; French, Linda M. (July 2015). "Dispatches from the Trojan Camp - Jovian Trojan L5 Asteroids Observed from CS3: 2014 October - 2015 January". The Minor Planet Bulletin. 42 (3): 216–224. Bibcode:2015MPBu...42R.216S. ISSN 1052-8091. Retrieved 13 June 2018.
18. Stephens, Robert D.; Coley, Daniel R.; Warner, Brian D.; French, Linda M. (October 2016). "Lightcurves of Jovian Trojan Asteroids from the Center for Solar System Studies: L4 Greek Camp and Spies". The Minor Planet Bulletin. 43 (4): 323–331. Bibcode:2016MPBu...43..323S. ISSN 1052-8091. Retrieved 13 June 2018.
19. Stephens, Robert D. (April 2017). "Lightcurve Analysis of Trojan Asteroids at the Center for Solar System Studies 2016 October - December". The Minor Planet Bulletin. 44 (2): 123–125. Bibcode:2017MPBu...44..123S. ISSN 1052-8091. PMC 7243949. PMID 32455395.

External links

• Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
• Dictionary of Minor Planet Names, Google books
• Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
• 884 Priamus at AstDyS-2, Asteroids—Dynamic Site
  • Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
• 884 Priamus at the JPL Small-Body Database
  • Close approach · Discovery · Ephemeris · Orbit viewer · Orbit parameters · Physical parameters