In the past few centuries, Eris was really a southern object, whose position around 1800 AD was within the southern constellation of Indus. Eris then crossed through Indus and into northern Tucanae until about 1817, before moving into southern Grus, where it stayed until the early 1840’s. From then it moved into Phoenix around 1874, then onto Sculptor until the 1930, and thence into the equatorial constellation of Cetus the Whale. Eris will remain within this constellation’s area between 2006 and 2015, and does not leave Cetus until 19th February 2037!
In the future, Eris will gradually move into the zodiac constellation of Pisces where it will stay until the 20th May 2060. It will cross back an forth between Cetus and Pisces several times for a decade or so, where it will move into Aries on 10 April 2065. Next it will leave Aries and become a northern object in the non-zodiacal constellation of Perseus sometime in June 2127. After 2175 AD, Eris will become a far northern object, residing in Camelopardalis until the 23rd Century, when the declination reaches its maximum of around +64oN in 2200 AD.
It should be noted that these positions and times remain tentative because the lack of historical data on the observed positions. So far the earliest identified position is from a plate made on 20th January 1963, meaning that we have orbital information based on just 43-years (2006) or just 7.7% of the entire orbit.
All sky positions given below should be sufficiently accurate for most amateur purposes, however, beyond the next few decades future ephemerides may change slightly with adjustments in the orbital elements. Perhaps the greatest difficulties are assessing the many perturbations caused by the gravitational pull of the other planets and planetary bodies in the Solar System. Better knowledge of these effects will likely be determined in the coming decades.
Telescopically, distant Eris only appears as a very faint ‘star’ but remains invisible to all amateur telescopes. It may also be possible to record the body by amateur deep CCD images, though its detection likely requires at least 30cm to 40cm apertures.
At times Eris can even outshine Pluto during its long orbit, reaching the maximum magnitude of about 15.5. When the dwarf planet is furthest from the Sun the brightness may drop as low as 18.8 magnitude!
Eris and Pluto : 1800-2200
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Mag. Mag. r Delta Elong L b
Min 18.8 16.0 97.6 98.5 178.8 360.0 40.9
Max 16.1 13.7 52.0 51.3 000.7 0.0 -44.6
Mean 18.2 15.3 84.7 84.7 089.3 129.8 -11.8
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0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o '
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--2005--
31 Dec 01 35.3 -05 38 18.8 96.71 96.89 100 Cet
--2006--
14 Jan 01 35.2 -05 36 18.8 96.94 96.89 086 Cet
28 Jan 01 35.3 -05 33 18.8 97.17 96.89 073 Cet
11 Feb 01 35.5 -05 29 18.8 97.39 96.88 059 Cet
25 Feb 01 35.8 -05 25 18.8 97.57 96.88 046 Cet
11 Mar 01 36.2 -05 20 18.8 97.71 96.88 033 Cet
25 Mar 01 36.7 -05 16 18.8 97.81 96.88 022 Cet
08 Apr 01 37.2 -05 12 18.8 97.85 96.88 014 Cet
22 Apr 01 37.7 -05 08 18.8 97.83 96.87 018 Cet
06 May 01 38.3 -05 05 18.8 97.76 96.87 028 Cet
20 May 01 38.8 -05 03 18.8 97.64 96.87 040 Cet
03 Jun 01 39.2 -05 02 18.8 97.48 96.87 053 Cet
17 Jun 01 39.5 -05 01 18.8 97.29 96.87 065 Cet
01 Jul 01 39.8 -05 01 18.8 97.07 96.86 078 Cet
15 Jul 01 39.9 -05 02 18.8 96.84 96.86 091 Cet
29 Jul 01 39.9 -05 04 18.8 96.61 96.86 104 Cet
12 Aug 01 39.8 -05 06 18.8 96.40 96.86 117 Cet
26 Aug 01 39.5 -05 09 18.8 96.21 96.86 130 Cet
09 Sep 01 39.2 -05 12 18.8 96.05 96.86 143 Cet
23 Sep 01 38.7 -05 15 18.7 95.95 96.85 155 Cet
07 Oct 01 38.3 -05 18 18.7 95.89 96.85 164 Cet
21 Oct 01 37.7 -05 21 18.7 95.89 96.85 164 Cet
04 Nov 01 37.2 -05 23 18.7 95.95 96.85 155 Cet
18 Nov 01 36.7 -05 24 18.7 96.06 96.85 142 Cet
02 Dec 01 36.3 -05 25 18.8 96.22 96.84 129 Cet
16 Dec 01 36.0 -05 24 18.8 96.41 96.84 116 Cet
30 Dec 01 35.8 -05 23 18.8 96.64 96.84 102 Cet
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0h UT (J2000) Mag Δ r El. Con
DATE R.A. Decl. V A.U. A.U. o
hh mm.m o '
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13 Jan 01 35.7 -05 21 18.8 96.87 96.84 088 Cet
27 Jan 01 35.8 -05 18 18.8 97.10 96.84 074 Cet
10 Feb 01 35.9 -05 14 18.8 97.32 96.83 060 Cet
24 Feb 01 36.2 -05 10 18.8 97.50 96.83 047 Cet
10 Mar 01 36.6 -05 06 18.8 97.65 96.83 034 Cet
24 Mar 01 37.1 -05 01 18.8 97.75 96.83 022 Cet
07 Apr 01 37.6 -04 57 18.8 97.79 96.83 015 Cet
21 Apr 01 38.2 -04 54 18.8 97.78 96.82 017 Cet
05 May 01 38.7 -04 50 18.8 97.72 96.82 027 Cet
19 May 01 39.2 -04 48 18.8 97.61 96.82 039 Cet
02 Jun 01 39.6 -04 46 18.8 97.45 96.82 051 Cet
16 Jun 01 40.0 -04 46 18.8 97.26 96.82 064 Cet
30 Jun 01 40.2 -04 46 18.8 97.04 96.81 077 Cet
14 Jul 01 40.4 -04 47 18.8 96.81 96.81 090 Cet
28 Jul 01 40.4 -04 48 18.8 96.58 96.81 103 Cet
11 Aug 01 40.3 -04 51 18.8 96.37 96.81 116 Cet
25 Aug 01 40.0 -04 53 18.8 96.17 96.81 129 Cet
08 Sep 01 39.7 -04 57 18.8 96.02 96.80 141 Cet
22 Sep 01 39.3 -04 60 18.7 95.90 96.80 153 Cet
06 Oct 01 38.8 -05 03 18.7 95.84 96.80 163 Cet
20 Oct 01 38.3 -05 05 18.7 95.84 96.80 165 Cet
03 Nov 01 37.8 -05 07 18.7 95.89 96.80 156 Cet
17 Nov 01 37.3 -05 09 18.7 95.99 96.79 144 Cet
01 Dec 01 36.9 -05 09 18.8 96.15 96.79 131 Cet
15 Dec 01 36.5 -05 09 18.8 96.34 96.79 117 Cet
29 Dec 01 36.3 -05 08 18.8 96.56 96.79 103 Cet
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The user applying this data for any purpose forgoes any liability against the author. None of the information should be used for regarding either legal or medical purposes. Although the data is accurate as possible some errors might be present. The onus of its use is place solely with the user.
