[mithrandir (Andrew)]

Originally Posted by Greg Bryant

The latest orbit determination from the Minor Planet Centre is given at the bottom of the below link.

http://www.minorplanetcenter.org/mpec/K11/K11A08.html

There's a chance that if the comet turns out to be very long period (which won't be known for a while longer), a very, very close approach to Earth in October is on the cards.

Those numbers match JPL. New values for Stellarium:

[Elenin_C2010_X1]
# Data taken from JPL/HORIZONS
# correct for the specified time frame:
# Start Time : A.D. 2011-Jan-05 00:00:00.0000 CT 
# Stop Time  : A.D. 2011-Jan-05 00:00:00.0000 CT 
name                        = Comet Elenin (C/2010 X1)              
parent                      = Sun
coord_func                  = comet_orbit
oblateness                  = 0.0
lighting                    = true
halo                        = true
color                       = 1.0,1.0,1.0
tex_halo                    = star16x16.png
tex_map                     = nomap.png
lighting                    = false
orbit_Epoch                 = 2455566.500000000
orbit_TimeAtPericenter      = 2455815.5800386025
orbit_PericenterDistance    = 0.4845932028112245
orbit_Eccentricity          = 0.9999975116715066
orbit_ArgOfPericenter       = 343.762694978635
orbit_AscendingNode         = 323.1999299462579
orbit_Inclination           = 1.836414212487844
radius                      = 34
albedo                      = 0.15
absolute_magnitude          = 10
slope_parameter             = 13.6
type                        = comet

The last 3 lines are only to be used with 0.10.6.1 or later