The binary Kuiper Belt Object 1998 WW31 
Christian Veillet - CFHT - April 17, 2002
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The discovery and subsequent study of the binary nature of the Kuiper Belt Object 1998 WW31 is a story whose three (for now) chapters are briefly presented hereafter and detailed in corresponding pages

The discovery of the duplicity of 1998 WW31 has been announced on April 16, 2001.  All the information relevant to the discovery itself is found on the page I prepared at that time. Here it is!.  It was both exciting (the first double KBO after Pluto/Charon!) and frustrating, as the data were not sufficient to use this discovery for determining the characteristics of the system.

Once turned this first page of solitary work, and with no hope of getting new observations before the following July (1998 WW31 was too close to the Sun), it was time to build a collaboration with all those who could have old images: With more data, we could be able to determine an orbit! Sharing information for a better knowledge of the binary system is the second chapter of this story, which you can find here.

With the obvious lack of a sufficient number of data, I proposed to the group to go ahead and ask for Director's Discretionary Time (DDT) on the Hubble Space Telescope. For normal HST observations, you have to apply once a year and you get the observations done before 9 and 21 months later (if you are awarded time). We wanted to get observations as soon as possible (early July): DDT serves just that purpose. We got one orbit on each of July, August and September. The orbit found was exciting enough to ask for three more observations in early 2002. This third chapter, the result of the close collaboration between three of us, is related here.

"More than one percent of the approximately 500 known KBOs are indeed binary: a puzzling fact for which many explanations will be proposed in what is going to be a very exciting and rapidly evolving field of research in the coming years..."


A pdf version of the paper published in  based on this story can be found here
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