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JPL Small-Body Database Browser
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16912 Rhiannon (1998 EP8)
Classification: Amor [NEO]          SPK-ID: 2016912
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

[ show orbit diagram ]
Orbital Elements at Epoch 2458600.5 (2019-Apr-27.0) TDB
Reference: JPL 55 (heliocentric ecliptic J2000)
 Element Value Uncertainty (1-sigma)   Units 
e .2727458819748417 9.1361e-08  
a 1.751124207517205 1.0143e-08 au
q 1.273512291090429 1.6324e-07 au
i 24.52087468028739 9.8089e-06 deg
node 169.206517286415 1.5253e-05 deg
peri 221.197948232211 2.5401e-05 deg
M 154.1618543011771 3.6727e-05 deg
tp 2458238.049853837110
(2018-Apr-29.54985384)
8.3534e-05 TDB
period 846.396491597235
2.32
7.3542e-06
2.013e-08
d
yr
n .4253325758955403 3.6956e-09 deg/d
Q 2.22873612394398 1.291e-08 au
  Orbit Determination Parameters
   # obs. used (total)      194  
   data-arc span      9738 days (26.66 yr)  
   first obs. used      1992-08-29  
   last obs. used      2019-04-28  
   planetary ephem.      DE431  
   SB-pert. ephem.      SB431-N16  
   condition code      0  
   norm. resid. RMS      .59523  
   source      ORB  
   producer      Otto Matic  
   solution date      2019-Sep-24 09:29:25  

Additional Information
 Earth MOID = .320845 au 
 Jupiter MOID = 3.30663 au 
 T_jup = 3.987 
[ show covariance matrix ]

Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]

Physical Parameter Table
Parameter Symbol Value Units Sigma Reference Notes
absolute magnitude H 17.8   n/a MPO416889  

16912 Rhiannon           Discovered 1998 Mar. 2 by ODAS at Caussols.
Rhiannon was a version of the celtic horse-goddess Epona and of sovereignty. She was mistress of the Singing Birds. Sometimes she appeared as a beautiful woman in dazzling gold on a white horse.
NOTE: some special characters may not display properly (any characters within {} are an attempt to place the proper accent above a character)
Reference: 20010309/MPCPages.arcLast Updated: 2009-05-11

[ hide close-approach data ]
Close-Approach Data   ...sorted by Date/Time (TDB)
Date/Time (TDB) Time Uncertainty
(days_HH:MM)
Body Nominal Distance (au) Minimum Distance (au) Maximum Distance (au) V-relative (km/s) V-infinity (km/s) JD (TDB) Time Uncertainty (minutes) Semi-major axis (km) Semi-minor axis (km) range-LOV angle (deg) N-sigma BP Orbit Ref. Reference Modified
1911-Jul-25 12:32 00:01 Mars 0.055923311011235 0.0559188970626147 0.0559277282216388 13.1915158080323 13.1911277246949 2419243.022357872 1.21282571639314 711.946281286247 22.5063802793267 -72.0728586729946 350922.924543566 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1934-Sep-13 19:48 < 00:01 Earth 0.410801597759564 0.410796128558527 0.410807067411073 12.3494293325963 12.3489041109958 2427694.324969281 0.512485874004438 762.076053248623 82.3781971694286 69.9290107740799 728248.129065062 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1941-Sep-21 03:01 < 00:01 Earth 0.321562691255858 0.321562246977272 0.321563135538155 12.5552340066372 12.554574022792 2430258.625632686 0.344345560198407 250.522800362844 21.6209881647399 -88.8898178310312 2120188.4117649 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1948-Sep-26 20:02 < 00:01 Earth 0.39825189414167 0.398247035270801 0.398256753047831 13.5495046159945 13.5490108297323 2432821.334902021 0.316266016918518 307.237704257173 34.5324602827533 38.2302491613058 1055422.23998962 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1985-Sep-15 04:19 < 00:01 Earth 0.38749253112732 0.38749128345343 0.387493778807575 12.3398118717482 12.3392546214771 2446323.679828796 0.149298967891287 164.630553829086 53.3921567579754 78.1646415875282 1084918.32522332 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1992-Sep-22 02:18 < 00:01 Earth 0.322129089064913 0.322128439846574 0.322129738283417 12.6593325293154 12.6586791237752 2448887.595658306 0.095632756288062 52.6131661332435 31.158740818921 78.0392805051117 1459805.91976458 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
1999-Sep-28 15:41 < 00:01 Earth 0.42374218748956 0.423741287961022 0.423743087018098 13.805922510461 13.8054670482135 2451450.153461941 0.109020832748358 45.644871107581 43.8743449926047 42.1637896224852 1363952.98507519 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2036-Sep-16 14:35 < 00:01 Earth 0.365306384017889 0.365303896741125 0.365308871306634 12.3351368356599 12.3345455170695 2464953.107945286 0.2045556209216 166.339968334821 41.6693484988712 -43.4946969326834 897385.471759504 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2043-Sep-24 03:08 < 00:01 Earth 0.329548778279353 0.329547741187812 0.329549815414261 12.7874777670418 12.7868454738633 2467516.630328023 0.172673928120774 224.658904424407 26.200284828803 78.4732328930755 1808928.47322709 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2050-Sep-29 18:28 < 00:01 Earth 0.457442663284429 0.457437943676254 0.457447382920088 14.1010596984096 14.1006466220889 2470079.269725040 0.220795252518261 295.650651150263 36.0541462935011 37.5765298614219 1168255.97442937 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2080-Sep-09 00:45 < 00:01 Earth 0.488503043237605 0.488495806567784 0.488510426977361 12.308558343749 12.3081151988929 2481016.531242937 0.639408221916076 13393.025824446 20.8274123174485 88.4428818883135 4616403.0005711 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2087-Sep-18 19:04 < 00:01 Earth 0.347822422485964 0.34781785477328 0.347826990273423 12.3508888785691 12.3502686275708 2483582.294341242 0.470312642749731 342.081704568295 19.2842055281898 -48.3544920011519 1899584.0567459 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2094-Sep-24 21:54 < 00:01 Earth 0.339742252334735 0.339738516706817 0.339745988186268 12.9369652528113 12.936359018435 2486145.412374023 0.378437299363632 477.647256099701 28.4463344059223 67.2875826132374 1616235.7930355 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2101-Oct-01 14:56 < 00:01 Earth 0.483901514472462 0.483891582070484 0.483911446948708 14.3491520950385 14.3487683569183 2488708.122391735 0.478890250780376 578.963853693921 37.8535237542428 31.2634276009837 998742.066714332 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2131-Sep-12 12:47 < 00:01 Earth 0.46356197582605 0.463550914990812 0.463573041365159 12.2906771060111 12.2902094387107 2499646.032739887 0.959191262880774 2499.11921860994 163.039588282027 77.799217537576 430441.282308238 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2138-Sep-20 19:16 < 00:01 Earth 0.336139789845113 0.336134592761281 0.336144987202447 12.3667715097283 12.3661305254893 2502211.303083925 0.688653856860789 544.131822884812 9.15786460859191 -61.5712842291317 4170495.50115092 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2141-Jan-11 02:51 00:02 Mars 0.048645572305881 0.0486437551835996 0.048647396268987 13.0152603106172 13.0148081241557 2503054.618892262 1.67089102696683 942.708441972428 22.2615014534266 84.6414798391944 323330.710910195 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2145-Sep-26 18:04 < 00:01 Earth 0.355663173696199 0.355655148231641 0.355671199650173 13.1144630609684 13.1138918028278 2504774.252839943 0.600175154282825 771.657534560874 29.9545497616065 58.8314615727441 1493378.75960017 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2182-Sep-14 00:40 00:02 Earth 0.437330055385298 0.43730938372585 0.437350727545984 12.2802233719648 12.2797272304842 2518275.527532109 1.79657343869219 1280.0800517228 238.790605894918 37.1199965453352 172122.297948318 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2189-Sep-21 17:50 00:01 Earth 0.326939364668125 0.326932736208129 0.326945994605465 12.4161480253147 12.4154916235487 2520840.243137366 1.33551069254362 1145.69639381699 14.2517243396069 -73.2441345907631 3122557.29607662 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29
2196-Sep-27 11:43 00:01 Earth 0.371886862110818 0.371868172365784 0.371905553427498 13.2935081313036 13.2929691536997 2523402.987995893 1.17841787656394 1524.36729043256 31.0730333324682 52.3246069084599 1397313.9666903 T 55 CATAB v2.0f-lin.ifort 2019-Sep-24 09:29:27 2019-Sep-24 09:29

Alternate Designations
 1998 EP8 = 1999 RN45 
Ephemeris | Orbit Diagram | Orbital Elements | Mission Design | Physical Parameters | Discovery Circumstances | Close-Approach Data ]
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