http://www.itelescope.net/sky-alertsMaciej Reszelski has produced some preliminary orbital elements for comet M503ujx (see below). The comet currently comes to perihelion on May 21.
Despite the magnitudes listed on the map, Michael Mattiazzo suggests it may possibly reach magnitude 6 in mid-May evening skies, passing through Eridanus and Lepus, with an Earth approach of 0.47AU.
Orbital elements: M503ujx
Perihelion 2015 May 21.866977 +/- 541 TT; Constraint: e=1
Epoch 2015 Apr 8.0 TT = JDT 2457120.5 Earth MOID: 0.1310 Reszelski
q 0.780478 +/- 4.35
H 9.9 G 0.15 Peri. 255.985 +/- 900
Node 109.350 +/- 80
e 1.0 +/- 0 Incl. 149.288 +/- 700
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