Asteroids 2007 VK184 and 2008 AF4 update thread

[silylene old]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;It's too short an arc to even worry about; and it may stay very short since it's such a tiny object...probably a few more days to work with though... <br />Posted by meteorwayne</DIV></p><p>I agree, and I&nbsp;usually&nbsp;begin to remember the asteroid's name after a 30 day arc....However, interestingly, after 5 days of arc now, the&nbsp;2008 ER7 risk has increased to a&nbsp;cumulative PS = -2.22</p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[silylene old]

<p>Some updates.&nbsp; 2008 AF4 remains Torino Scale 1, and its risk increases slightly.&nbsp; 2008 ER7 is maintaining its spot on the list with more data points and arc.</p><p>&nbsp; <table border="0" cellspacing="1" cellpadding="2" class="srt"><tbody><tr class="th"><td><br />Object

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Some updates.&nbsp; Posted by silylene</DIV></p><p>And another, 2008 AF4 moves up in risk once again.</p><p><font size="2">Analysis based on<br />584 observations spanning 64.725 days<br />(2008-Jan-10.39652 to 2008-Mar-15.1213)</font></p><p><br /><table border="1" cellspacing="0" cellpadding="5" bgcolor="#ffffff"><tbody><tr valign="bottom" bgcolor="#cccccc"><td><strong>Object<br />Designation</strong>

 

[silylene old]

<p>Agree, 2008 AF4 is becoming increasingly interesting.</p><p>My&nbsp;prime asteroid watch list is:</p><p>1950 AD (a concern rather far in the future)</p><p>2004 MN4 Apophis</p><p>2007 VK184</p><p>2008 AF4</p><p>&nbsp;</p><p>Other interesting asteroids, which need more data:</p><p>1994 WR12 (will this small asteroid ever get rediscovered?)</p><p>2008 ER7</p><p>2008 EC69</p><p>&nbsp;</p><p>&nbsp;A new asteroid&nbsp;we need to watch&nbsp;with a lowish Palermo scale is 2008 EC69.&nbsp; It will have 118 near passes of the earth in the next 86 years, witha&nbsp; close one in June 2018.&nbsp; It is a *big*&nbsp; asteroid, estimated 1.2 km diameter.&nbsp; The current arc is just 6 days, so much more data and time will be needed to assess risks.</p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[Philotas]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>And another, 2008 AF4 moves up in risk once again.Analysis based on584 observations spanning 64.725 days(2008-Jan-10.39652 to 2008-Mar-15.1213)ObjectDesignationYearRangePotentialImpactsImpactProb.(cum.)Vinfinity(km/s)H(mag)Est.Diam.(km)PalermoScale(cum.)PalermoScale(max.)TorinoScale(max.)2008 AF42078-210085.3e-0511.6619.7&nbsp;0.390-1.94-2.021DateDistanceWidthSigmaImpactSigmaLOVStretchLOVImpactProbabilityImpactEnergyPalermoScaleTorinoScaleYYYY-MM-DD.DD(rEarth)(rEarth)&nbsp;&nbsp;(rEarth)&nbsp;(MT)&nbsp;&nbsp;2078-01-09.71&nbsp;0.23&nbsp;&nbsp;3.93e-03&nbsp;&nbsp;0.000&nbsp;&nbsp;2.96138&nbsp;&nbsp;7.27e+05&nbsp;&nbsp;1.3e-08&nbsp;&nbsp;2.55e+03&nbsp;&nbsp;-5.47&nbsp;&nbsp;0&nbsp;2089-01-09.48&nbsp;0.05&nbsp;&nbsp;7.21e-04&nbsp;&nbsp;0.000&nbsp;&nbsp;-0.20834&nbsp;&nbsp;1.79e+04&nbsp;&nbsp;4.4e-05&nbsp;&nbsp;2.55e+03&nbsp;&nbsp;-2.02&nbsp;&nbsp;1&nbsp; <br />Posted by meteorwayne</DIV></p><p>&nbsp;</p><p>&nbsp;</p><table border="1" cellpadding="5"><tbody><tr><td><h3>Impact Probability: 5.3e-05</h3><p>0.005300000% chance of Earth impact </p><p>or </p><p>1 in 19,000 chance </p><p>or </p><p><strong>99.99470000% chance the asteroid will miss the Earth </strong></p>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;&nbsp;Impact Probability: 5.3e-050.005300000% chance of Earth impact or 1 in 19,000 chance or 99.99470000% chance the asteroid will miss the Earth Hmm, I feel safe still.. <br />Posted by philotas</DIV></p><p>Absolutely </p><p>These asteroid threads were started in response to a panicked individual. However it has been an interesting exercise in watching the process of the risk changing as new observations are added. That's why we've continued them.<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>

 

[silylene old]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;&nbsp;Impact Probability: 5.3e-050.005300000% chance of Earth impact or 1 in 19,000 chance or 99.99470000% chance the asteroid will miss the Earth Hmm, I feel safe still.. <br />Posted by philotas</DIV></p><p>&nbsp;</p><p>I agree the risk of collision, <em>from existing data</em>, is small.&nbsp; Given the asteroid's size (390m diameter) and speed (11.7 km/s) using the UArizon impact effects simulation package,&nbsp;an impact&nbsp;would release 1510 MegaTons of energy (TNT equivalent), and make a crater 5.9 km in diameter, and destroy all houses within a 50 km radius.&nbsp;&nbsp; if it hit the ocean, the resultant tsunami would create far more devastation.</p><p>Assuming that if this hit, 25 million people would die, then the averaged risk is about:</p><p>25,000,000x0.000053 = 1325 people dying.&nbsp; This asteroid is thus about the same risk to humanity as the number of people who die on average each year from all earthquakes combined.</p><p>risks of some other asteroids:</p><p>1950DA:&nbsp; 1 in 300&nbsp; (?&nbsp; models may not be so good extrapolating this far forwards)</p><p>VK184:&nbsp; 1 in 2940</p><p>2004 MN4 Apophis:&nbsp; 1 in 45000</p><p>1994 WR12:&nbsp; 1 in 10000</p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[Philotas]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;I agree the risk of collision, from existing data, is small.&nbsp; Given the asteroid's size (390m diameter) and speed (11.7 km/s) using the UArizon impact effects simulation package,&nbsp;an impact&nbsp;would release 1510 MegaTons of energy (TNT equivalent), and make a crater 5.9 km in diameter, and destroy all houses within a 50 km radius.&nbsp;&nbsp; if it hit the ocean, the resultant tsunami would create far more devastation.Assuming that if this hit, 25 million people would die, then the averaged risk is about:25,000,000x0.000053 = 1325 people dying.&nbsp; This asteroid is thus about the same risk to humanity as the number of people who die on average each year from all earthquakes combined.risks of some other asteroids:1950DA:&nbsp; 1 in 300&nbsp; (?&nbsp; models may not be so good extrapolating this far forwards)VK184:&nbsp; 1 in 29402004 MN4 Apophis:&nbsp; 1 in 450001994 WR12:&nbsp; 1 in 10000 <br />Posted by silylene</DIV></p><p>At which diameters does asteroids&nbsp;start to become&nbsp;a threat to the human civilization?</p><p>&nbsp;</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>

 

[silylene old]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>At which diameters does asteroids&nbsp;start to become&nbsp;a threat to the human civilization?&nbsp;&nbsp; <br />Posted by philotas</DIV></p><p>Philotas,&nbsp; try working with this website, and simulate your own asteroid collisions.&nbsp; It is very&nbsp;easy to use, interesting:</p><p>http://www.lpl.arizona.edu/impacteffects/</p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[Philotas]

Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Philotas,&nbsp; try working with this website, and simulate your own asteroid collisions.&nbsp; It is very&nbsp;easy to use, interesting:http://www.lpl.arizona.edu/impacteffects/ <br />Posted by silylene</DIV><br /><br />Heh, thanks alot. I'll slam tens of asteroids into the Earth&nbsp;and see what I get. <div class="Discussion_UserSignature"> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Heh, thanks alot. I'll slam tens of asteroids into the Earth&nbsp;and see what I get. <br />Posted by philotas</DIV><br /><br />Once again, more observations, and the risk increases again.</p><p>Rather unique, and interesting.</p><p>As philotas poitned out, the odds are still quite low, but 2008 AF4 is now the highest risk threat we have on our plate. Far higher than Apophis, that we hear about so often.</p><p>&nbsp;<font size="2">Analysis based on<br />587 observations spanning 69.969 days<br />(2008-Jan-10.39652 to 2008-Mar-20.36578)</font></p><p><font size="2">I had to edit the abbreviation for cumulative which should go below Impact Prob, and the first Palemo scale column.</font></p><p><font size="2">Sheesh, how often is that a threat to the profanity flilter?? Sheesh...</font></p><p><table border="1" cellspacing="0" cellpadding="5" bgcolor="#ffffff"><tbody><tr valign="bottom" bgcolor="#cccccc"><td><strong>Object<br />Designation</strong>

 

[silylene old]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Once again, more observations, and the risk increases again.Rather unique, and interesting.As philotas poitned out, the odds are still quite low, but 2008 AF4 is now the highest risk threat we have on our plate. Far higher than Apophis, that we hear about so often.&nbsp;Analysis based on587 observations spanning 69.969 days(2008-Jan-10.39652 to 2008-Mar-20.36578)I had to edit the abbreviation for cumulative which should go below Impact Prob, and the first Palemo scale column.Sheesh, how often is that a threat to the profanity flilter?? Sheesh...ObjectDesignationYearRangePotentialImpactsImpactProb.Vinfinity(km/s)H(mag)Est.Diam.(km)PalermoScalePalermoScale(max.)TorinoScale(max.)2008 AF42089-210066.1e-0511.6619.7&nbsp;0.390-1.88-1.971 <br />Posted by MeteorWayne</DIV></p><p>&nbsp;</p><p>New data in, and 2008 AF4 got downgraded to&nbsp;Torino Scale 0, and Palermo Scale -2.77<br /></p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;New data in, and 2008 AF4 got downgraded to&nbsp;Torino Scale 0, and Palermo Scale -2.77 <br />Posted by silylene</DIV></p><p>That from NEODyS?</p><p>JPL hasn't updated yet. Is that -2.77 Max or cumulative?</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>

 

[silylene old]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>That from NEODyS?JPL hasn't updated yet. Is that -2.77 Max or cumulative? <br />Posted by MeteorWayne</DIV></p><p>NEODyS.&nbsp; -2.77 for both max and cumulative.</p><p>Also,&nbsp; 2008 ER7 was downgraded to PS cumulative -4.04</p> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>NEODyS.&nbsp; -2.77 for both max and cumulative.Also,&nbsp; 2008 ER7 was downgraded to PS cumulative -4.04 <br />Posted by silylene</DIV></p><p>That's Right NEODyS doesn't go out far enough to capture the other potential impacts that JPL does, so the Max and cumultive are the same.</p><p>&nbsp;Like I say, any 2008 Es or Fs are just noise until there's a 30 day arc....<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>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>That's Right NEODyS doesn't go out far enough to capture the other potential impacts that JPL does, so the Max and cumultive are the same.&nbsp;Like I say, any 2008 Es or Fs are just noise until there's a 30 day arc.... <br />Posted by MeteorWayne</DIV></p><p>Finally, JPL has done an update including the Apr 3 and 5 observations.</p><p>They have caused a major shift in the orbit.</p><p>NEODys, which does not go out as far in time as JPL as Jan 9, 2089; the Palermo scale numbers are similar. -2.92 JPL and -2.93 NEODyS. JPL has a second virtual impactor in 2099, PS -2.69. NEODys doesn't go out that far in time.</p><p>However, since the magnitude of the object is ~ +20, we are coming up on the last observations of this asteroid before it becomes too dim to see. Then we will have to wait for a while (decades) to see it again and refine the orbit. It is the 3rd or 4th riskiest asteroid, so for our lifetime, it's nothing to worry about. For our children and grandchildren, maybe </p><p>Realize that both of these are at 1/1000 of the "backgound" rate so are low probablity.</p><p>And they are 80 years away...</p><p>&nbsp;</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>