Asteroid 25143 Itokawa.

[3488]

I think these objects fill the entire spectrum Some are more asteroid (rocky or carbonaceous) others more icy.<br /><br />Comet 107P/Wilson-Harrington appears to be a hybrid!!!<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[3488]

Hi MeteorWayne,<br /><br />I think that you are correct & have hit the nail right on the head!!!!<br /><br />Comet & / or asteroid 107P/Wilson-Harrington, backs up your statements. I would like to see a mission go there (maybe like NEAR Shoemaker or Hayabusa). Deep Space 1 was to have done, but its navigation camera packed up before hand, but was sent to Comet Borelly instead (so it was not a failure)!!!<br /><br />Andrew Brown. <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[centsworth_II]

<font color="yellow">'I know you asked Jon...'</font><br /><br />I'm glad to see everyone's thoughts.<br /><br />I wonder what the true distrbution is? <div class="Discussion_UserSignature"> </div>

 

[JonClarke]

Count me in with those who thinks there is a complete spectrum from very ice rich bodies to ones that are completely rocky. That then raises the question of how you distinguish between asteroids and comets.<br /><br />Note that the etymology of "comet" comes from the latin for "hair". Thus a comet is a hairy star, e.g. emits tails or a halo of dust and gas. <br /><br />An "asteroid" is "star like" in small to medium telescopes - e.g. no visble cometary behaviour.<br /><br />Some asteroids reportedbly occasionally do show comet like behaviour, and some short period comets are inert most of the time. One can easily imagine a comet losing most and eventually all of its near surface ices and become asteroid like in its behaviour<br /><br />Comets often have highly inclined, highly elliptical, and even retrograde orbits. Aaseroids may have ellipitical and incline orbts, but to a lesser degree. None have retorgrade orbits, as far as I know. However since cometary orbits can be modified through graviational and non graviational effects their orbits too can evolve into being asteroid like.<br /><br />The actual ice and rock cotent of any small body in the solar system will depend on where it formed and its subsequent history.<br /><br />Cheers (back from holiday!)<br /><br />Jon <div class="Discussion_UserSignature"> <p><em>Whether we become a multi-planet species with unlimited horizons, or are forever confined to Earth will be decided in the twenty-first century amid the vast plains, rugged canyons and lofty mountains of Mars</em>  Arthur Clarke</p> </div>

 

[3488]

Found these, taken very close to or on the surface during the descent to the <br />tiny asteroid 25143 Itokawa, in November 2005. Not exactly news as is well over <br />two years old, but just found them myself.<br /><br />During decent to Asteroid 25143 Itokawa. Thursday 3rd November 2005.<br /><br />Another here. Friday 4th November 2005.<br /><br />Also here from same date.<br /><br />Here on: Tuesday 8th November 2005.<br /><br />Another here on: Wednesday 9th November 2005.<br /><br />This one I think is from the actual surface: Saturday 12th November 2005 & maybe this <br />& also this from the same date.<br /><br />Another here on Saturday 19th November 2005.<br /><br />Asteroid 25143 Itokawa (brighter object) & Regulus / Alpha Leonis (top right) Monday 29th August 2005.<br /><br />Very distant mug shot of planet Mars from Hayabusa: Tuesday 11th November 2003.<br /><br />Andre <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>