16974 Iphthime

16974 Iphthime (/ɪfˈθm/; prov. designation: 1998 WR21) is a Jupiter trojan and a binary system from the Greek camp, approximately 57 kilometers (35 miles) in diameter. It was discovered on 18 November 1998, by astronomers with the Lincoln Near-Earth Asteroid Research at the ETS Test Site in Socorro, New Mexico.[1] The dark Jovian asteroid belongs to the 80 largest Jupiter trojans and has a notably slow rotation of 78.9 hours.[10] It was named after Iphthime from Greek mythology.[1] The discovery of its companion by Hubble Space Telescope was announced in March 2016.

16974 Iphthime
Hubble Space Telescope image of Iphthime taken in 2013
Discovery[1]
Discovered byLINEAR
Discovery siteLincoln Lab's ETS
Discovery date18 November 1998
Designations
(16974) Iphthime
Pronunciation/ɪfˈθm/[2]
Named after
Iphthime Iphthīmē/Ἰφθῑμη[1]
(Greek mythology)
1998 WR21 · 1974 WX
1986 WS
Jupiter trojan[1][3]
Greek[4] · background[5]
Orbital characteristics[3]
Epoch 23 March 2018 (JD 2458200.5)
Uncertainty parameter 0
Observation arc42.86 yr (15,655 d)
Aphelion5.5556 AU
Perihelion4.8248 AU
5.1902 AU
Eccentricity0.0704
11.82 yr (4,319 d)
261.74°
 5m 0.24s / day
Inclination15.036°
241.56°
134.72°
Jupiter MOID0.0605 AU
TJupiter2.9270
Physical characteristics
Mean diameter
55.43±4.0 km[6]
57.15±3.85 km[7]
57.34±0.33 km[8]
78.9±0.4 h[9]
0.065±0.010[8]
0.066±0.009[7]
0.0691±0.011[6]
C(assumed)[10]
V–I = 0.960±0.035[10]
9.80[1][3][6][7][8]

    Orbit and classification

    Iphthime is a dark Jovian asteroid orbiting in the leading Greek camp at Jupiter's L4 Lagrangian point, 60° ahead of its orbit in a 1:1 resonance .[4] It is also a non-family asteroid in the Jovian background population.[5]

    It orbits the Sun at a distance of 4.8–5.6 AU once every 11 years and 10 months (4,319 days; semi-major axis of 5.19 AU). Its orbit has an eccentricity of 0.07 and an inclination of 15° with respect to the ecliptic.[3] The body's observation arc begins with its first observation as 1974 WX at Crimea-Nauchnij in November 1974, or 24 years prior to its official discovery observation at Socorro.[1]

    Naming

    This minor planet was named from Greek mythology after Iphthime, sister of Penelope and daughter of Icarius. Iphthime appears in her sister's dream to comfort her as she is grieving. The official naming citation was published by the Minor Planet Center on 3 December 2017 (M.P.C. 107739).[11]

    Physical characteristics

    Iphthime is an assumed C-type asteroid.[10] Its V–I color index of 0.96 is typical for D-type asteroids, the most common spectral type among the larger Jupiter trojans.[10]

    Rotation period

    Iphthime and its companion imaged by the Hubble Space Telescope in 2018

    In October 2009, a rotational lightcurve of Iphthime was obtained for the first time by Stefano Mottola from photometric observations during seven nights at the Calar Alto Observatory in Spain. Lightcurve analysis gave a long rotation period of 78.9±0.4 hours or 3.3 days with a brightness amplitude of 0.25 magnitude (U=2+).[10][9]

    Diameter and albedo

    According to the surveys carried out by the Infrared Astronomical Satellite IRAS, the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Iphthime measures between 55.43 and 57.341 kilometers in diameter and its surface has an albedo between 0.065 and 0.069.[6][7][8] The Collaborative Asteroid Lightcurve Link adopts the results obtained by IRAS, that is an albedo of 0.0691 and a diameter of 55.43 kilometers based on an absolute magnitude of 9.8.[10]

    100+ largest Jupiter trojans
    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 Hektor7.2225233230.99L46.920.9301907list
    617 Patroclus8.19140.362140.92140.85L5102.800.8301906list
    911 Agamemnon7.89131.038166.66185.30L46.590.9801919list
    588 Achilles8.67130.099135.47133.22L47.310.9401906list
    3451 Mentor8.4126.288116.30117.91L57.700.7701984list
    3317 Paris8.3118.790116.26120.45L57.090.9501984list
    1867 Deiphobus8.3118.220122.67131.31L558.660.9301971list
    1172 Äneas8.33118.020142.82148.66L58.710.9501930list
    1437 Diomedes8.3117.786164.31172.60L424.490.8101937list
    1143 Odysseus7.93114.624125.64130.81L410.110.8601930list
    2241 Alcathous8.64113.682114.63118.87L57.690.9401979list
    659 Nestor8.99112.320108.87107.06L415.980.7901908list
    3793 Leonteus8.7112.04686.2687.58L45.620.7801985list
    3063 Makhaon8.4111.655116.14114.34L48.640.8301983list
    1583 Antilochus8.6108.842101.62111.69L431.540.9501950list
    884 Priamus8.81101.09396.29119.99L56.860.9001917list
    1208 Troilus8.99100.477103.34111.36L556.170.7401931list
    1173 Anchises8.8999.549126.27120.49L511.600.7801930list
    2207 Antenor8.8997.65885.1191.32L57.970.9501977list
    2363 Cebriones9.1195.97681.8484.61L520.050.9101977list
    4063 Euforbo8.795.619102.46106.38L48.850.9501989list
    2357 Phereclos8.9494.62594.9098.45L514.390.9601981list
    4709 Ennomos8.591.43380.8580.03L512.280.6901988list
    2797 Teucer8.789.430111.14113.99L410.150.9201981list
    2920 Automedon8.888.574111.01113.11L410.210.9501981list
    (15436) 1998 VU309.187.64685.7178.63L48.970.8701998list
    3596 Meriones9.287.38075.0973.28L412.960.8301985list
    2893 Peiroos9.2386.88487.4686.76L58.960.9501975list
    4086 Podalirius9.185.49586.8985.98L410.430.8701985list
    4060 Deipylos9.384.04379.2186.79L49.300.7601987list
    1404 Ajax9.383.99081.6996.34L429.380.9601936list
    4348 Poulydamas9.582.03270.0887.51L59.910.8401988list
    5144 Achates9.080.95891.9189.85L55.960.9201991list
    4833 Meges8.980.16587.3389.39L414.250.9401989list
    2223 Sarpedon9.4177.48094.63108.21L522.740.8801977list
    (4489) 1988 AK9.076.59592.9395.02L412.580.9501988list
    2260 Neoptolemus9.3176.43571.6581.28L48.180.9501975list
    5254 Ulysses9.276.14778.3480.00L428.720.9701986list
    (3708) 1974 FV19.375.66179.5976.75L56.550.9801974list
    2674 Pandarus9.174.26798.10101.72L58.481.0001982list
    3564 Talthybius9.473.73068.9274.11L440.590.9001985list
    4834 Thoas9.172.33186.8296.21L418.190.9501989list
    (7641) 1986 TT69.471.83968.9775.28L427.770.9801986list
    3540 Protesilaos9.370.22576.8487.66L48.950.9401973list
    (11395) 1998 XN779.868.97764.7167.78L417.381998list
    (4035) 1986 WD9.668.73368.2366.99L413.470.9701986list
    5264 Telephus9.468.47273.2681.38L49.530.9701991list
    1868 Thersites9.568.16370.0878.89L410.480.9601960list
    (9799) 1996 RJ9.668.03364.8772.42L421.520.9101996list
    4068 Menestheus9.567.62562.3768.46L414.400.9501973list
    (23135) 2000 AN1469.966.23058.2968.50L48.690.8602000list
    2456 Palamedes9.365.91691.6699.60L47.240.9201966list
    3709 Polypoites9.165.29799.0985.23L410.041.0001985list
    1749 Telamon9.564.89881.0669.14L416.980.9701949list
    3548 Eurybates9.663.88572.1468.40L48.710.7301973list
    4543 Phoinix9.763.83662.7969.54L438.871.2001989list
    12444 Prothoon9.863.83564.3162.41L515.821996list
    4836 Medon9.563.27767.7378.70L49.820.9201989list
    (16070) 1999 RB1019.763.19164.1368.98L520.240.9601999list
    (15440) 1998 WX49.662.51966.4871.88L421.430.9701998list
    (4715) 1989 TS19.762.09763.9165.93L58.810.8501989list
    (34746) 2001 QE919.861.68460.5163.63L519.630.9502001list
    (38050) 1998 VR389.861.60361.0450.44L418.850.9901998list
    5130 Ilioneus9.760.71159.4052.49L514.770.9601989list
    5027 Androgeos9.659.78657.86n.a.L411.380.9101988list
    (6090) 1989 DJ9.459.56874.5381.92L418.480.9801989list
    (5648) 1990 VU19.759.29563.91n.a.L537.560.9001990list
    7119 Hiera9.759.15076.4077.29L44000.9501989list
    4805 Asteropaios10.057.64753.1643.44L512.371990list
    16974 Iphthime9.857.34155.4357.15L478.90.9601998list
    4867 Polites9.857.25158.2964.29L511.241.0101989list
    2895 Memnon10.056.70655.67n.a.L57.500.7101981list
    4708 Polydoros9.954.96455.67n.a.L57.520.9601988list
    (21601) 1998 XO8910.054.90955.6756.08L412.650.9701998list
    (12929) 1999 TZ19.954.07761.0455.34L59.270.8801999list
    17492 Hippasos10.053.97555.67n.a.L517.751991list
    5652 Amphimachus10.153.92153.1652.48L48.371.0501992list
    2759 Idomeneus9.953.67661.0152.55L432.380.9101980list
    (5258) 1989 AU110.253.27550.77n.a.L419.851.0101989list
    (12126) 1999 RM1110.153.202n.a.n.a.L5n.a.?1999list
    (15502) 1999 NV2710.053.10055.6750.86L515.130.8751999list
    4754 Panthoos10.053.02553.1556.96L527.681977list
    4832 Palinurus10.052.05853.16n.a.L55.321.0001988list
    5126 Achaemenides10.551.92244.2248.57L453.021989list
    3240 Laocoon10.251.69550.77n.a.L511.310.8801978list
    4902 Thessandrus9.851.26361.0471.79L47380.9601989list
    11552 Boucolion10.151.13653.1653.91L532.441993list
    (20729) 1999 XS14310.450.96146.30n.a.L45.721.0001999list
    (6545) 1986 TR610.150.95153.16n.a.L416.260.9101986list
    4792 Lykaon10.150.87053.16n.a.L540.090.9601988list
    21900 Orus10.050.81055.6753.87L413.450.9501999list
    1873 Agenor10.150.79953.7654.38L520.601971list
    5028 Halaesus10.250.77050.77n.a.L424.940.9001988list
    2146 Stentor9.950.75558.29n.a.L416.401976list
    4722 Agelaos10.050.37853.1659.47L518.440.9101977list
    5284 Orsilocus10.150.15953.16n.a.L410.310.9701989list
    11509 Thersilochos10.149.96053.1656.23L517.371990list
    5285 Krethon10.149.60658.5352.61L412.041.0901989list
    4791 Iphidamas10.149.52857.8559.96L59.701.0301988list
    9023 Mnesthus10.149.15150.7760.80L530.661988list
    5283 Pyrrhus9.748.35664.5869.93L47.320.9501989list
    4946 Askalaphus10.248.20952.7166.10L422.730.9401988list
    (22149) 2000 WD4910.248.19050.7750.37L47.841.0902000list
    (32496) 2000 WX18210.248.01750.7751.63L523.340.9502000list
    5120 Bitias10.247.98750.77n.a.L515.210.7801988list
    12714 Alkimos10.147.81961.0454.62L428.481991list
    (7352) 1994 CO9.947.73155.67 47.07L56480.8501994list
    1870 Glaukos10.647.64942.23n.a.L55.991971list
    4138 Kalchas10.146.46253.1661.04L429.20.8101973list
    (23958) 1998 VD3010.246.00150.7747.91L45620.9901998list
    4828 Misenus10.445.95446.30 43.22L512.870.9201988list
    4057 Demophon10.145.68353.16n.a.L429.821.0601985list
    4501 Eurypylos10.445.52446.30n.a.L46.051989list
    4007 Euryalos10.345.51548.4853.89L46.391973list
    5259 Epeigeus10.344.74142.5944.42L418.421989list
    30705 Idaios10.444.54646.30n.a.L515.741977list
    16560 Daitor10.743.86151.4243.38L51991list
    (15977) 1998 MA1110.443.53046.3051.53L52500.9061998list
    7543 Prylis10.642.89342.23n.a.L417.801973list
    4827 Dares10.542.77044.22n.a.L519.001988list
    1647 Menelaus10.542.71644.22n.a.L417.740.8661957list
    (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.

    References

    1. "16974 Iphthime (1998 WR21)". Minor Planet Center. Retrieved 18 June 2018.
    2. Noah Webster (1884) A Practical Dictionary of the English Language
    3. "JPL Small-Body Database Browser: 16974 Iphthime (1998 WR21)" (2017-09-28 last obs.). Jet Propulsion Laboratory. Retrieved 18 June 2018.
    4. "List of Jupiter Trojans". Minor Planet Center. 1 June 2018. Retrieved 18 June 2018.
    5. "Asteroid (16974) Iphthime – Proper Elements". AstDyS-2, Asteroids – Dynamic Site. Retrieved 18 June 2018.
    6. Tedesco, E. F.; Noah, P. V.; Noah, M.; Price, S. D. (October 2004). "IRAS Minor Planet Survey V6.0". NASA Planetary Data System – IRAS-A-FPA-3-RDR-IMPS-V6.0: IRAS-A-FPA-3-RDR-IMPS-V6.0. Bibcode:2004PDSS...12.....T. Retrieved 18 June 2018.
    7. 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. Retrieved 18 June 2018. (online, AcuA catalog p. 153)
    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. (online catalog)
    9. 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.
    10. "LCDB Data for (16974) Iphthime". Asteroid Lightcurve Database (LCDB). Retrieved 18 June 2018.
    11. "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 18 June 2018.
    This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.