Comet Christensen 2006 W3

Comet Christensen was discovered on November 18th, 2006 by Eric Christensen of the Catalina Sky Surveys (Arizona) with a 0.68  meter Schmidt Telescope.
At that time the comet was still more than 8 AU from the sun and had a total apparent brightness of about 18th magnitude.

The comet was discovered on 18 November 2006 by Eric J. Christensen with a Schmidt telescope measuring 0.68 m in diameter.
The Comet appeared as an object of 18th magnitude and showed a small crown, slightly elongated. 
 In the days immediately following, other astronomers repeated the observations, confirming the cometary nature.
However, it was not possible to identify a queue .  It was then about 8 AU from the Sun (closer to the orbit of Saturn than to that of Jupiter.)

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The brightness of the comet has increased over time. In 2007 it went from 18th to 16th magnitude.
During 2008 the increase in brightness was more sudden and at the end of the year, the comet had reached 11th magnitude.
As the perihelion transit approached on July 6, 2009, the comet reached 8th magnitude.
It then began to tread the descending branch of the brightness curve increasingly becoming weaker as it moved away from the sun and Earth
on it's journey to the depths of the outer solar system


In the period between 1 and 8 November 2009, Comet Christensen was observed with the Herschel Space Observatory .
The aim of the research was to identify the behavior of comets far away from the Sun.
Previous analyzes had indicated that the production of a crown was associated with the sublimation of "hypervolatile ice"
 such as CO and CO 2 or the release of gaseous material trapped in ice water and released following the reorganization of this in the crystalline form. 


Christensen 06-23-2009
Comet Christensen has manifested a particularly active nucleus, which produced a dense coma despite the great distance maintained by the Sun. 
The data collected indicate that this activity consisted above all in the release of CO (which has exceeded at least 220% the production of water vapor )

Comet Christensen follows a highly eccentric retrograde orbit , about 127 ° inclined to the ecliptic plane .
The perihelion was reached on 6 July 2009, at a distance of about 3 UA from the Sun.
The descending node, between the orbits of Jupiter and Mars , was crossed at about 3.5 AU from the Sun.


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