Massive amounts of water released by comet hit

[drwayne]

Over the weekend of 9-10 July 2005 a team of UK and US scientists, led by Dr. Dick Willingale of the University of Leicester, used NASA's Swift satellite to observe the collision of NASA's Deep Impact spacecraft with comet Tempel 1. <br /><br />Reporting today (Tuesday) at the UK 2006 National Astronomy Meeting in Leicester, Dr. Willingale revealed that the Swift observations show that the comet grew brighter and brighter in X-ray light after the impact, with the X-ray outburst lasting a total of 12 days. <br /><br />"The Swift observations reveal that far more water was liberated an d over a longer period than previously claimed," said Dick Willingale. <br /><br />Swift spends most of its time studying objects in the distant Universe, but its agility allows it to observe many objects per orbit. Dr. Willingale used Swift to monitor the X-ray emission from comet Tempel 1 before and after the collision with the Deep Impact probe. <br /><br />The X-rays provide a direct measurement of how much material was kicked up after the impact. This is because the X-rays were created by the newly liberated water as it was lifted into the comet's thin atmosphere and illuminated by the high-energy solar wind from the Sun. <br /><br />"The more material liberated, the more X-rays are produced," explained Dr. Paul O'Brien, also from the University of Leicester. <br /><br />The X-ray power output depends on both the water production rate from the comet and the flux of subatomic particles streaming out of the Sun as the solar wind. Using data from the ACE satellite, which constantly monitors the solar wind, the Swift team managed to calculate the solar wind flux at the comet during the X-ray outburst. This enabled them to disentangle the two components responsible for the X-ray emission. <br /><br />Tempel 1 is usually a rather dim, weak comet with a water production rate of 16,000 tonnes per day. However, after the Deep Impact probe hit the comet this rate increased to 40,000 tonnes per day over th <div class="Discussion_UserSignature"> <p>"1) Give no quarter; 2) Take no prisoners; 3) Sink everything."  Admiral Jackie Fisher</p> </div>

 

[vogon13]

Interesting.<br /><br />Thanx for the post.<br /><br /> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[michaelmozina]

Ok, I admit it, I don't get it....<br /><br />Try as I might, I can't quite fathom the one to one correlation between the presence of x-rays and the presense of water.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>The X-rays provide a direct measurement of how much material was kicked up after the impact. This is because the X-rays were created by the newly liberated water as it was lifted into the comet's thin atmosphere and illuminated by the high-energy solar wind from the Sun.<br /><br />"The more material liberated, the more X-rays are produced," explained Dr. Paul O'Brien, also from the University of Leicester. <p><hr /></p></p></blockquote><br /><br />Could someone who understands this process better than I do explain to me how they know that these particular x-rays are produced by water molecules and *only* water molecules? I don't quite fathom how these folks make that connection of x-rays to water vapor. <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[jatslo]

x-ray spectrum

 

[yevaud]

http://www.esa.int/esaCP/SEMXA46DIAE_index_0.html<br /><br /> <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[jatslo]

Here is a periodic table:<br /><br />http://isotopes.lbl.gov/xray/mainpage.htm<br />

 

[bonzelite]

if they were talking about Enceladus follow-up data confirming it as a truly water-logged body, i'd stop yawning. <br /><br />

 

[mlorrey]

bonz, you're one of the "theres no water in those comets" arguers. Now you want to downplay it?

 

[jatslo]

Yep, just a news article... Grasping at straws, I bet ...

 

[colesakick]

They're guessing, there is not one confirmed (in the lab I mean) test they sited that specifically demonstrated that water ice can or does generate x-rays under any condition they guess at as the “potential” causes of the observed x-rays. C’mon, be more demanding of their explanations versus gratuitous guesswork! <div class="Discussion_UserSignature"> Intellectual honesty means being willing to challenge yourself instead of others </div>

 

[colesakick]

Also, it is ignorant to count OH radicals in the tail as caused water vapor only when other known (electrical) processes could give rise to those! Now that white-hot heat is on the books for cemetery life experience, well . . . seems clear reason to sidle up to the electrical model for a change. It is clearly the best fit with the readings. <div class="Discussion_UserSignature"> Intellectual honesty means being willing to challenge yourself instead of others </div>

 

[telfrow]

<font color="yellow">C’mon, be more demanding of their explanations versus gratuitous guesswork!</font><br /><br />Is a disagreement between the observers "demanding" enough?<br /><br />The following snips are from this article from New Scientist: <br /><br /><i>But other Deep Impact observers disagree with the Swift team's interpretation of their data. Carey Lisse, who led the Deep Impact observations using NASA's Spitzer Space Telescope and Chandra X-ray Observatory says that, while the Swift data agree very well with his own group's, "our interpretations differ quite substantially".<br /><br />Lisse told New Scientist: "We can show, using measurements of the comet – from other observatories as well as Swift and Chandra – that the outburst [from four to six days after the impact] was due to a dramatic upswing in the solar wind hitting the comet, and not due to an increased amount of material coming off the comet."<br /><br />Since both the rate of water production and the number of solar wind particles striking the comet's environment affect the X-ray signal, it is important to take both factors into account when studying a comet's environment. Both groups have taken data from one of NASA's solar wind-monitoring spacecraft – the Advanced Composition Explorer (ACE) – into account, but in different ways.<br /><br />Lisse says the X-ray burst is almost all solar-wind driven while Willingale's team says it was largely due to an increase in the comet's water production rate.</i><br />----<br /><br /><i><b>Deep Impact's principal investigator Mike A'Hearn at the University of Maryland, US, says: "What this illustrates is that doing science is hard." And he emphasises the positive side of such varying interpretations. "The fact that we have many separate measurements says that we can catch discrepancies that you wouldn't catch in another case," he says.</b></i> <div class="Discussion_UserSignature"> <strong><font color="#3366ff">Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild.</font> - <font color="#3366ff"><em>Tennyson</em></font></strong> </div>

 

[bonzelite]

<font color="yellow"><br />bonz, you're one of the "theres no water in those comets" arguers. Now you want to downplay it?</font><br /><br />no, sir. if you've been following my post history, i'm not on record as ever denying water to exist as a volatile component of cometary material. my post history will show that i maintain a position of yes there is water, no it is not the primary material responsible for cometary structure. <i>in my opinion, that i have maintained throughout my post history, is that a comet is defined more by it's dust content than it's ice content.</i><br /><br />furthermore, as many others would probably agree, we currently do not really understand the nature of layering in the coma, ie, the variations in composition as arranged farther and farther down into the core. <br /><br />if one wishes to back me into the dirty snowball corner, then forget it. i am not whatsoever buying into that for one minute.

 

[bonzelite]

<font color="yellow"><br />Lisse says the X-ray burst is almost all solar-wind driven while Willingale's team says it was largely due to an increase in the comet's water production rate. </font><br />thank you, telfrow, for that post. how balanced of you. <br /><br />