Apophis chances to hit earth dramatically increased!

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schmack

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<p>&nbsp;</p><p>http://news.ninemsn.com.au/article.aspx?id=447795</p><p>From the article - </p><p>&nbsp; <font color="#993300">13-year-old German schoolboy corrected NASA's estimates on the chances of an asteroid colliding with Earth, a German newspaper has reported, after spotting the boffins had miscalculated.</font></p><p><font color="#993300">Nico Marquardt used telescopic findings from the Institute of Astrophysics in Potsdam (AIP) to calculate that there was a 1 in 450 chance that the Apophis asteroid will collide with Earth, the Potsdamer Neuerster Nachrichten reported.</font></p><p><font color="#993300">NASA had previously estimated the chances at only 1 in 45,000 but told its sister organisation, the European Space Agency (ESA), that the young whizzkid had got it right.</font></p><p><font color="#000000">I wonder how NASA got it so wrong? It must have been a simple mistake for a teenager to have been able to correct it. Not that it really makes much diofference.&nbsp; If it hits we're stuffed. Regardless as to how soon it was predicted or not.</font></p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p><font size="4" color="#ff0000"><font size="2">Assumption is the mother of all stuff ups</font> </font></p><p><font size="4" color="#ff0000">Gimme some Schmack Schmack!</font></p> </div>
 
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KosmicHero

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Well it matters if the difference in time is enough to do something about it.&nbsp; I think that the American Institute for Aeronautics and Astronautics with the Planetary Society did a design competition for a mission to Apophis.&nbsp; Maybe we'll need those designs after all.<br /> <div class="Discussion_UserSignature"> kosmichero.wordpress.com </div>
 
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Smersh

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According to the article in the op, if the asteroid does impact the Earth, it is likely to crash into the Atlantic Ocean on 13th April 2029 (a Friday.) <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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Philotas

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Any reliable sources regarding this? <div class="Discussion_UserSignature"> </div>
 
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bearack

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>According to the article in the op, if the asteroid does impact the Earth, it is likely to crash into the Atlantic Ocean on 13th April 2029 (a Friday.) <br />Posted by Smersh</DIV></p><p><br />They also stated it would be a 1 and 45,000 chance.&nbsp; If they screwed the pooch on that one, think their impact analysis might be a tad flawed?</p> <div class="Discussion_UserSignature"> <p><br /><img id="06322a8d-f18d-4ab1-8ea7-150275a4cb53" src="http://sitelife.space.com/ver1.0/Content/images/store/6/14/06322a8d-f18d-4ab1-8ea7-150275a4cb53.Large.jpg" alt="blog post photo" /></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>They also stated it would be a 1 and 45,000 chance.&nbsp; If they screwed the pooch on that one, think their impact analysis might be a tad flawed? <br />Posted by bearack</DIV><br /><br />The JPL impact risk page info on Apophis has not changed as of now.</p><p>It is the second most likely impactor in this century.</p><p><table border="1" cellspacing="0" cellpadding="5" bgcolor="#ffffff"><tbody><tr valign="bottom" bgcolor="#cccccc"><td><strong>Object<br />Designation</strong>
 
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Smersh

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The JPL impact risk page info on Apophis has not changed as of now.It is the second most likely impactor in this century.ObjectDesignationYearRangePotentialImpactsImpactProb.(cum.)Vinfinity(km/s)H(mag)Est.Diam.(km)PalermoScale(cum.)PalermoScale(max.)TorinoScale(max.)2007 VK1842048-205743.4e-0415.6322.0&nbsp;0.130-1.82-1.83199942 Apophis (2004 MN4)2036-203722.2e-055.8719.7&nbsp;0.250-2.52-2.520Those odds are&nbsp; 1 in 45,454.I''ll keep an eye out to see if there's any change.I'll keep an eye out for any update. To me, the odds of impact with a satellte affecting the trajectory significantly seem far fetched. We're talking about a quarter km sized asteroid traveling at 13 km/sec hitting a satellite. It's like a bug on a windshield.&nbsp; <br /> Posted by MeteorWayne</DIV></p><p>Hmmm ... that JPL page is not likely to change, by the looks, if <strong>this </strong>article in The Register is correct. They </p><p>reckon the schoolboy was wrong, and NASA was right.&nbsp;</p> <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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MeteorWayne

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<p>The more I investigate this story, the more I question it.</p><p>The last observations reported by any observatory were from Mauna Kea on Aug 16, 2006; 20 months ago. Prior to that, Mt Hopkins and Mt Lemmon Surveys covered the earlier part of 2006. I see no observations at all from the observatory mentioned in the article on the NEODyS page which documents them. </p><p>SO I sure would like to see some facts before buying into this yet. The last previous news story about Apophis was in February when a US team of students won a grant to develop a mission to send a spcecraft to rendevous with it to increase accuracy of mass and path.</p><p>It (on paper) is scheduled for launch is 2012 with rendevous during the close approach of 2017.</p><p>So far neither JPL nor NEODyS has changed anything on their pages regarding this asteroid.</p><p>From NEODyS:</p><p>"<font size="2"><strong>Near-Earth Asteroid (99942) Apophis [2004 MN4]: current status</strong> <br /><br />The asteroid (99942) Apophis (previously designated as 2004 MN4) will have a very close approach to Earth in 2029. The observations collected in the months of December 2004 and January 2005 by professional and amateur astronomers have provided enough information to exclude the possibility of an impact in 2029. At the end of January 2005, radar observations performed at Arecibo have led to a substantial improvement of the orbit; as a consequence, the list of post-2029 Virtual Impactors has changed. The coworkers of NEODyS/CLOMON2 will continue to process additional observational data as they become available, with the aim of removing the remaining Virtual Impactors as soon as possible. <br /><br />Andrea Milani, Maria Eugenia Sansaturio, Giovanni B. Valsecchi "</font><br /></p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Hmmm ... that JPL page is not likely to change, by the looks, if this article in The Register is correct. They reckon the schoolboy was wrong, and NASA was right.&nbsp; <br />Posted by Smersh</DIV><br /><br />Thanx, a snippet from the Register article:</p><p>"</p><p>There's only one problem with the story: the kid's sums are in fact wrong, NASA's are right, and the ESA swear blind they never said any different. An ESA spokesman in Germany told the <em>Reg</em> this morning: "A small boy did do these calculations, but he made a mistake... NASA's figures are correct."</p><p>It would appear that the intial article in the <em>Potsdamer Neueste Nachrichten</em>, which says that NASA and the ESA endorsed Nico Marquardt's calculations, was incorrect. The story was picked up by German tabloids and the AFP news wire, and is now all over the internet.</p><p>Marquardt apparently reckoned that the odds of the well-known Apophis asteroid hitting Earth were not one in 45,000 as assessed by NASA, but rather one in 450. Apophis will pass close by Earth in 2029 and 2036, so close that it will come nearer than satellites in geostationary orbit.</p><p>It seems that Marquardt's calculations included the possibility of collision with a satellite in some way not thought to have been covered by NASA, which bumped up the odds of a subsequent Earth strike. But NASA says:</p><blockquote>[The asteroid will pass] within the distance of Earth's geosynchronous satellites. However, because Apophis will pass interior to the positions of these satellites at closest approach, in a plane inclined at 40 degrees to the Earth's equator and passing outside the equatorial geosynchronous zone when crossing the equatorial plane, it does not threaten the satellites in that heavily populated region.</blockquote> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p>Here's the current NASA/JPL page on Apophis.</p><p>http://neo.jpl.nasa.gov/apophis/</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Here's the current NASA/JPL page on Apophis.http://neo.jpl.nasa.gov/apophis/ <br />Posted by MeteorWayne</DIV><br /><br />And for the science geeks among us, the paper published in Icarus, which so far is the last word on the subject.</p><p>http://neo.jpl.nasa.gov/apophis/Apophis_PUBLISHED_PAPER.pdf</p><p>&nbsp;</p><p>And as I pointed out earlier, so far 2007 VK184 is a substantially higher risk.</p><p>The odds are 1 in 2941 for this 130 meter sized object impacting in 2048.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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Smersh

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Actually Wayne, I reckon your "bug on a windshield" comment just about sums it up doesn't it? Surely a relatively tiny satellite would have no effect on a 200 billion ton lump of rock, travelling at such a huge velocity. <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Actually Wayne, I reckon your "bug on a windshield" comment just about sums it up doesn't it? Surely a relatively tiny satellite would have no effect on a 200 billion ton lump of rock, travelling at such a huge velocity. <br />Posted by Smersh</DIV></p><p>&nbsp;</p><p>While I may well be right, I'm happier that it will pass well outside of Geostationary orbit as it passes the equator so we don't have to test the theory! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-laughing.gif" border="0" alt="Laughing" title="Laughing" /><br /></p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Well it matters if the difference in time is enough to do something about it.&nbsp; I think that the American Institute for Aeronautics and Astronautics with the Planetary Society did a design competition for a mission to Apophis.&nbsp; Maybe we'll need those designs after all. <br />Posted by KosmicHero</DIV></p><p>&nbsp;</p><p>Here's a BBC article:</p><p><br />http://news.bbc.co.uk/2/hi/science/nature/7265608.stm</p><p>Unfortunately, the Panetary Society Web Page appears to be down at the moment.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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Smersh

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<p><strong>Here's</strong> another article, in "Universe Today" which seems to back up The Register article. However, they seem to be backpedalling, as apparently Universe Today ran the story themselves originally, saying the schoolboy had got it right.</p><p><strong><font color="#008000">Also, the scientist mentioned in AFP's story said he wasn't conferred with either by the news agency. So don't give any heed to this story that has been running amok around the internet. </font></strong></p> <p><strong><font color="#008000">But here's our story on this as it originally ran: Here&rsquo;s a story that supports the value of science fairs. And it also makes one wonder where else NASA&rsquo;s decimal points might be off by a couple of places. One caveat on this news piece, however: as far as I know there hasn&rsquo;t been an official NASA press release on this.</font></strong></p><p>Please click on the link, to see the whole article, and the story as they originally reported it. &nbsp;</p> <p><strong>&nbsp;</strong></p> <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Here's another article, in "Universe Today" which seems to back up The Register article. However, they seem to be backpedalling, as apparently Universe Today ran the story themselves originally, saying the schoolboy had got it right.Also, the scientist mentioned in AFP's story said he wasn't conferred with either by the news agency. So don't give any heed to this story that has been running amok around the internet. But here's our story on this as it originally ran: Here&rsquo;s a story that supports the value of science fairs. And it also makes one wonder where else NASA&rsquo;s decimal points might be off by a couple of places. One caveat on this news piece, however: as far as I know there hasn&rsquo;t been an official NASA press release on this.Please click on the link, to see the whole article, and the story as they originally reported it. &nbsp; &nbsp; <br />Posted by Smersh</DIV></p><p>Rats, I searched UT and didn't find it.</p><p>Here's the comment from Don Yeomans, a name familar to all of us who watch these rocks in space:</p><p>""We have not corresponded with this young man and this story is absurd, a hoax or both. During its 2029 Earth close approach, Apophis will approach the Earth to about 38,900 km, well inside the geosynchronous distance at 42,240 km. However, the asteroid will cross the equatorial belt at a distance of 51,000 km - well outside the geosynchronous distance. Since the uncertainty on Apophis' position during the Earth close approach is about 1500 km, Apophis cannot approach an Earth satellite. Apophis will not cross the moon's orbital plane at the Moon's orbital distance so it cannot approach the moon either." <br /></p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p>The Planetary Society site is back up, here's the announcement about the competition award:</p><p>http://planetary.org/programs/projects/apophis_competition/</p><p>&nbsp;</p><p>Here's a detailed list of the proposals, some great thinking in there!!</p><p>http://planetary.org/programs/projects/apophis_competition/winners.html</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The Planetary Society site is back up, here's the announcement about the competition award:http://planetary.org/programs/projects/apophis_competition/ <br />Posted by MeteorWayne</DIV><br /><br />In reading through the paper, it's clear that not much refinement in orbit will occur before 2011, when the next high quality optical observations will occur.</p><p>After that, in 2013, radar observations from Arecibo (IF it's still operating) will provide a great reduction in uncertainty and could exclude a future impact. If only Goldstone data is available, it won't help much. Beyond that, in 2021 much better radar obs from Arecibo (if it's operating) and Goldstone will further greatly reduce the uncertainty. A mission like the one suggested that would plant a transponder on the surface would allow +/- 2 meter ranging and would also further reduce the uncertainty.</p><p>Seems to me this makes a good case for saving Arecibo (and maybe the earth in the process) and creating a mission to land a transponder on the surface of Apophis.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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Smersh

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>The Planetary Society site is back up, here's the announcement about the competition award:http://planetary.org/programs/projects/apophis_competition/ <br /> Posted by MeteorWayne</DIV></p><p>I just took a look at that Planetary Society competition page. I agree and it also sounds to me that tagging Apophis might be adviseable.&nbsp; (As you said about the transponder, providing funds can be made available, of course.)&nbsp;</p><p>Also, I just noticed that before this was all "debunked," I said about the&nbsp; date for potential impact: "it is likely to crash into the Atlantic Ocean on 13th April 2029 (a Friday.)"&nbsp; In actual fact, the date was in 2036, after the asteroid had been deflected ever so slightly by a satellite in geostationary orbit. That would make more sense anyway I should think, as&nbsp; the course change, if any, would be so slight that several years would be required before it could become an impactor, later in its orbit.</p><p>I'm now applying for a job with The Sun, as a headline writer. <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-undecided.gif" border="0" alt="Undecided" title="Undecided" /> </p> <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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DengarReturns

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<p align="justify"><font size="3"><font color="#993366">I've got a couple questions&nbsp;about the NASA Page on Apophis&nbsp;below, (In particular,&nbsp;note paragraphs 3 & 4.&nbsp;):</font>&nbsp; &nbsp;</font></p><p align="justify">&nbsp;</p><p align="justify"><font size="3"><font color="#993366">1.&nbsp;&nbsp;Those&nbsp;are a hell of a lot of variables, (and large ones at that.)&nbsp; But I&nbsp;also suspected that there had to be a high degree of possibility of its trajectory changing in that time span.&nbsp; </font></font></p><p align="justify"><font size="3" color="#993366">2.&nbsp; What about&nbsp;the gravitational fluctuation&nbsp;depending on where&nbsp;Apophis passes over the earth.&nbsp; -Whether it passes over&nbsp;land or sea?&nbsp; </font></p><p align="justify"><font size="3">3.&nbsp; <font color="#993366">Perhaps most importantly,</font>&nbsp;<font color="#993366">and please correct me if I'm wrong,&nbsp;isn't this&nbsp;essentially saying that&nbsp;at this point NASA&nbsp;really doesn't know how close Apophis will pass by us, or even if it will hit the Earth on its way&nbsp;around, which does seem to be possible if I'm reading this correctly.&nbsp; Am I wrong?</font>&nbsp; </font></p><p align="justify">&nbsp;</p><p align="justify"><font size="3">"Trajectory predictions for asteroids are normally based on a standard model of the solar system that includes the gravity of the Sun, Moon, other planets, and the three largest asteroids. <br /><br />However, additional factors can influence the predicted motion in ways that depend on rarely known details, such as the spin of the asteroid, its mass, the way it reflects and absorbs sun-light, radiates heat, and the gravitational pull of other asteroids passing nearby. These were examined, along with the effect of Earth's non-uniform gravity field during encounters, and limitations of the computer hardware performing the calculations. <br /><br />One would normally look for the influence of such factors as they gradually alter the trajectory over years. But, for Apophis, the changes remain small until amplified by passage through Earth's gravity field during the historically close approach in 2029. <br /><br /><strong>For example, the team found solar energy can cause between <u>20 and 740 km (12 and 460 miles) of position change over the next 22 years</u> leading into the 2029 Earth encounter. <u>But, only 7 years later, the effect on Apophis' predicted position can grow to between 520,000 and 30 million km (323,000 and 18.6 million miles</u>; 0.0035-0.2 AU). <em>This range makes it difficult to predict if Apophis will even have a close encounter with Earth in 2036 when the orbital paths intersect. </em></strong></font></p><table border="0" cellspacing="2" cellpadding="10" width="190" align="right"><tbody><tr><td>&nbsp;
 
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MeteorWayne

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Posted by DengarReturns</DIV><br /><br />That's exactly the point of future optical and radar observations. Without accurate models of the shape an rotation of Apophis, and depending on the exact pass through the keyhole (if it occurs) the physical properties of the object&nbsp;are in the same&nbsp;error range as the gravitational&nbsp;uncertainty in position. With the close approaches in 2011 and 2013 enough will be known to state whether this object is a danger or not.</p><p>Until at least 2011 (and probably 2013) we just speculate.</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
 
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DengarReturns

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>With the close approaches in 2011 and 2013 enough will be known to state whether this object is a danger or not.Until at least 2011 (and probably 2013) we just speculate. <br />Posted by MeteorWayne</DIV></p><p><font size="2" color="#993366">Ok, and Crap!&nbsp; </font></p><p><font size="2" color="#993366">But&nbsp;my point is, why isn't this being more clearly stated at this point, -rather than seeming to state the reverse?&nbsp; </font></p> <div class="Discussion_UserSignature"> </div>
 
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Smersh

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font size="3"><strong>For example, the team found solar energy can cause between <u>20 and 740 km (12 and 460 miles) of position change over the next 22 years</u> leading into the 2029 Earth encounter. <u>B</u></strong></font> <br /> Posted by DengarReturns</DIV></p><p>It seems that 2036 is very much the critical encounter then, even if it doesn't hit us perhaps? Would it be possible for it to plough into some geostationary satellites in 2036 (I guess there might be considerably more of them by then, in any case,) altering the asteroid's course infinitessimally, so that it could strike us next time round after that? (Does anyone know when that is btw?)</p><p>Here's a graphic from ESA showing all the "space debris" currently around Earth:</p><p><br /> <img src="http://sitelife.space.com/ver1.0/Content/images/store/14/7/9e23e6e4-79e9-4c15-b7de-7780fe4a336c.Medium.jpg" alt="" /></p><p><strong>Click here for hi-res image.&nbsp;</strong></p><h1>Space debris: evolution in pictures</h1><p id="gallabs"><font color="#003300"><strong>Between the launch of Sputnik on 4 October 1957 and 1 January 2008, approximately 4600 launches have placed some 6000 satellites into orbit, of which about 400 are travelling beyond geostationary orbit or on interplanetary trajectories.<br /><br />Today, it is estimated that only 800 satellites are operational - roughly 45 percent of these are both in LEO and GEO. Space debris comprise the ever-increasing amount of inactive space hardware in orbit around the Earth as well as fragments of spacecraft that have broken up, exploded or otherwise become abandoned. About 50 percent of all trackable objects are due to in-orbit explosion events (about 200) or collision events (less than 10).</strong></font></p><p><font color="#003300"><strong>Link&nbsp;</strong></font></p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <h1 style="margin:0pt;font-size:12px">----------------------------------------------------- </h1><p><font color="#800000"><em>Lady Nancy Astor: "Winston, if you were my husband, I'd poison your tea."<br />Churchill: "Nancy, if you were my wife, I'd drink it."</em></font></p><p><font color="#0000ff"><strong>Website / forums </strong></font></p> </div>
 
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Philotas

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<p><span class="bold">NASA debunks it officially:&nbsp;</span></p><p>&nbsp;</p><p><span class="bold">http://www.nasa.gov/home/hqnews/2008/apr/HQ_08103_student_asteroid_calculations.html</span></p><p>&nbsp;</p><p><span class="bold"><font color="#0000ff">NASA Statement on Student Asteroid Calculations </font></span></p><p><font color="#0000ff">WASHINGTON -- The Near-Earth Object Program Office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., has not changed its current estimates for the very low probability (1 in 45,000) of an Earth impact by the asteroid Apophis in 2036.<br /><br />Contrary to recent press reports, NASA offices involved in near-Earth object research were not contacted and have had no correspondence with a young German student, who claims the Apophis impact probability is far higher than the current estimate.<br /><br />This student's conclusion reportedly is based on the possibility of a collision with an artificial satellite during the asteroid's close approach in April 2029. However, the asteroid will not pass near the main belt of geosynchronous satellites in 2029, and the chance of a collision with a satellite is exceedingly remote. <br /><br />Therefore, consideration of this satellite collision scenario does not affect the current impact probability estimate for Apophis, which remains at 1 in 45,000.</font></p><p>&nbsp;</p><p>&nbsp;</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>
 
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Jem

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<p>Just thinking would NASA really tell us anyway, A few people have asked me if they would really tell us if it was going to hit, to stop world panic, people would stop going to work, shops being raided, and theres nothing they would be able to do to bring peace back. I remember when it was all over the news even my family started to panic!&nbsp;</p><p>&nbsp;</p><p>So maybe nasa only said it wasn't going to hit to stop world panic. And a smart 13 year old figured it out! </p><p>&nbsp;</p><p>Just a thought, Please don't rip me apart&nbsp;<img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-smile.gif" border="0" alt="Smile" title="Smile" />&nbsp;</p> <div class="Discussion_UserSignature"> <span style="font-family:Arial" class="Apple-style-span"><span style="font-size:medium" class="Apple-style-span"><span style="color:#0000ff" class="Apple-style-span">“</span></span><span style="font-size:medium" class="Apple-style-span"><span style="color:#0000ff" class="Apple-style-span">That intelligent creatures exist in outerspace is proven by the fact that they have not contacted us.</span></span><span style="font-size:medium" class="Apple-style-span"><span style="color:#0000ff" class="Apple-style-span">”</span></span></span> </div>
 
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