Asteroids 2007 VK184 and 2008 AF4 update thread

[silylene old]

I decided to start a new thread on asteroid 2007 VK184, just because it is fun to monitor new asteroids, and keep abreast of the latest observational data.<br /><br />Interestingly, the popular press has not reported on this yet!<br /><br />So I decided to start this by first re-posting from the first mention from 5 Jan 2008 thread on the Martian asteroid: <font color="black"><br />"On a side note, asteroid 2007 VK184 has just been rated a Torino Scale 1 concern by JPL and NEODYS based on 100 observations spanning 54 days. The object is 0.13 km in diameter, and is a danger to earth in the year 2048. </font>font color=yellow>Please understand that as more observational data is acquired in the next few months, the chance of an earth strike very likely diminish to nil. "<br /> <br />edit to add the other Torino Scale 1 asteroid to the thread title <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]

Newest information 12 jan 2008: More observational data in on VK184 (60 days worth). The odds of impact with the earth on 2048 was increased to 0.03%. It is now Palermo Scale = -1.83, and Torino Scale 1. <br /> <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]

Interestingly, 2007 VK184 also made a very close keyhole pass to earth on 26 May 1980. It got within 0.001213 a.u. or 113,000 miles or 181,500km, about half the distance from earth to the moon. link Noboday even knew it was there! <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>

 

[brellis]

thanks for the info, silylene<br /><br />I had a good time playing with the JPL small body browser for this little tyke.<br /><br />Amazing that nobody noticed the 1980 close encounter. We might have seen a Heaven's Gate-type of purple sneaker cult for that event! <img src="/images/icons/laugh.gif" /><br /><br />I wonder if any current SDC members will still be around to *bump* this thread in 2048. With a little luck, I'll be 85 y.o. then! <img src="/images/icons/shocked.gif" /> <div class="Discussion_UserSignature"> <p><font size="2" color="#ff0000"><em><strong>I'm a recovering optimist - things could be better.</strong></em></font> </p> </div>

 

[MeteorWayne]

Looks like an interesting few decades between this and Apophis <img src="/images/icons/smile.gif" /><br /><br />Thanx for starting the thread. Certainly a Torino 1 deserves it's own thread even though it will likely drop to a zero.<br /><br />Should be interesting to see which winds up the more dangerous asteroid in the long run.<br /><br />I notice 2007 VK184 has a VERY low inclination orbit, which means there could be future interactions with Mars and Jupiter as well. Lots of uncertainlty.<br /><br />Unfortunately I'll be 96 by 2048, but if I live that long, I'll be out meteor observing at 2:15 AM on June 3 when it comes the closest <img src="/images/icons/smile.gif" /> <br /><br />MW <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]

Ill be 90 yrs old then. I plan to be around, and will be watching for this. <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]

I should point out that asteroid 2008 AF4, an Apophis sized object is currently a higher risk than Apophis, with 54 impacts between 2084 and 2099. Edit: It is also a Toirino scale 1<br /><br />Of course, we'll all be worm food by then.<br /><br />Also this is based on only 1 day of observations, so should be considered VERY VERY VERY preliminary.<br /><br />MW <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]

Speaking of worm food, asteroid 1950 AD has a 1 in 300 chance of destroying civilization in the year 2880. We had a good thread discussing this a couple of years ago. The past trajectory is well understood with about 55 years of observation. Predicting the future trajectory is problematic (also discussed in the old thread), but the best estimations give a 0.3% chance of collision. link <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]

If you will permit me, I really don't give a rats patoot about something that will happen 800 years after my demise.<br /><br />Unless, of course, reincarnation or time travel works <img src="/images/icons/smile.gif" /> <img src="/images/icons/laugh.gif" /> <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]

2008 AF4 now has 5 days of observations, and still remains Torino Scale 1, Palermo Scale = - 2.22. Impact probability is 1 in 42,000. Maximum danger is in the year 2084. It's a pretty big impactor, as these things go. <br /><br />edited: fixed an insignificant typo on Palermo Scale <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]

Hmm, that's not reflected on the JPL's NEO Risk page.<br />It still shows just a day of observations.<br /><br />Where did you hear that? <br /><br />Edit: Added data.<br /><br />Analysis based on<br />42 observations spanning 1.1138 days<br />(2008-Jan-10.39652 to 2008-Jan-11.51032) <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>

 

[logicize]

Neo Dys has it's closest pass at 0.000982 au in 2070. Harvard has it at 0.00250 au.<br /><br />0.0033459 au for 2005 YU55 in 2011 after a pass of 0.0129934 au in 2010. Harvard has it at 0.00108 au.

 

[silylene old]

from hohmanntransfer, which is quoting from NEODys.<br /><br /><blockquote><font class="small">In reply to:</font><hr /><p>2008 AF4 NEODyS 1629 2086-2090 13 2.29e-05 -2.22 -2.24 1 NEODyS: "Based on 60 optical observations (of which 1 are rejected as outliers) from 2008/01/10.397 to 2008/01/15.204. NOTE: The Virtual Impactor in 2089/01/09.479 in the table above is rated as Torino Scale 1." <p><hr /></p></p></blockquote><br /><br />(I took the impact odds from the 1.1 observation days. The odds might actually be higher with the new data.) <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]

Thanx. It's nice to have many pairs of eyes searching for the latest. <br /><br />Edit, the NEODys page gives a Torino +1, a Palermo -4.<br /><br />These are all different ways of estimating the risk to the earth of an impact.<br /><br />With not much to go on, it's a crapshoot, much as life in our solar system.<br /><br />I look forward to the JPL NEO page including the latest observations.<br />It does give more detail of the risk and scales. <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]

OK, the NEO site has been updated.<br /><br /><br />Analysis based on<br />59 observations spanning 4.8063 days<br />(2008-Jan-10.39652 to 2008-Jan-15.20285<br /><br /><br />Torino Scale (maximum) 1 <br />Palermo Scale (maximum) -2.24 <br />Palermo Scale (cumulative) -2.10 <br />Impact Probability (cumulative) 3.1e-05 <br />Number of Potential Impacts 53 <br /><br />highest probability impact Jan 9 2089.<br /> <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>

 

[logicize]

I still haven't forgotten about 2005 YU55. I'm still wondering why there is such a great difference in the estimates for this object. From 0.000983 to (0.008724 or 0.006749) is a pretty vast difference. With that kind of uncertainty, how can anyone say it will not hit. Anyway it's not too big so it shouldn't hurt to much if it does, but it is a close call and it is pretty soon.<br /><br /><br />Harvard<br /><br />0.00108 au <br /><br />http://cfa-www.harvard.edu/iau/lists/Dangerous.html<br /><br /><br />NeoDys<br /><br />0.006749 au, 0.008724 au NeoDys (2010 and 2011 listed)<br /><br />http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?quicksearch:0;search<br /><br /><br />Original source was JPL although I can no longer find the data there.<br /><br />0.000983 au, even closer to Venus 0.00060 au.<br /><br />http://www.hohmanntransfer.com/h22/wk060101.htm#K05Y55U<br /><br /><br />The Russians.<br /><br />.0017 au<br /><br />http://neopage.nm.ru/ENG/GENERAL/DATA/pha01.txt

 

[MeteorWayne]

Your name is logicize. Use logic!!<br /><br />A first tentative orbit is created from a day of observations. The errors in measurements are huge relative to the position accuracy. Hence the orbit projection errors are huge. Thousands of possible orbits can fit the orbservations.<br /><br />3 days later, with new observations, you now have a 3 day arc of data.<br />The position accuracy improves. The orbital projections improve. Only hundreds of orbits can fit the observations.<br /><br />2 days later, using the tentaltive orbit, images are discovered from a year ago. Now the current orbit has to fit a year's worth of oservations.<br />Now dozens of orbits can fit.<br /><br />The accuracy and the error bars shrink dramatically.<br /><br />Why is this such a hard concept to understand?<br /><br />Using the latest and earliest observations, 2006 YU 55 is a Torino 1, a Palermo cumulative -3.87. It is 20th on the list of possible impactors.<br />Why the heck are you worked up about it? The most likely impact is in 2036, with odds of 1 in 1 million or worse.<br /><br />Unless something changes, it's not an issue.<br /><br />Your first link doesn't list it in the first 50<br />Your second link doesn't work.<br />Your third link refers to obs from 2 years ago.<br /><br />On your 4th link there are e dozen or more closer approaches than this asteroid.<br /><br />Do you just want to panic about nothing? It seems so to me.<br /><br />Wayne<br /> <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>

 

[logicize]

Your correct, the best way is to enter 2005YU55 in the following page.<br /><br />http://newton.dm.unipi.it/cgi-bin/neodys/neoibo?quicksearch:0;main<br /><br />Date of first obs. (yr/mo/day) 2005/12/24.29832 <br />Date of last obs. (yr/mo/day) 2006/01/23.15924 <br /><br />Let's narrow it down to these two.<br /><br />NeoDys<br /><br />0.006749 au, 0.008724 au NeoDys (2010 and 2011 listed)<br /><br />Harvard. (updated 01/16/2008)<br /><br />http://cfa-www.harvard.edu/iau/lists/Dangerous.html<br /><br />0.00108 au<br /><br />You would think being almost 2 years since the last sighting the Harvard and NeoDys numbers would match. I'm not personally concerned about it, after all, I said it's relatively small. Odds are, everything will be fine, it will most likely hit the ocean anyway. I just think the difference in estimates is interesting since they have access to the same data. I also think it's interesting because it is the soonest/closest event in the next several years.

 

[silylene old]

<font color="yellow">Odds are, everything will be fine, it will most likely hit the ocean anyway. </font><br /><br />Given the trajectory uncertainties, the chance of even hitting the earth is very small. <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>

 

[logicize]

<font color="yellow">Given the trajectory uncertainties, the chance of even hitting the earth is very small.</font><br /><br />That's my point. It will be very close and there seems to be at least some level of uncertainty. It looks like maybe as late as March of 2010 before the next chance for observation. Unless the current Mercury mission can get some new data on it.

 

[silylene old]

A close approach of 0.006749 au is still about 1,009,000 km from earth, or three times the earth-moon distance. That is not that close. <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>

 

[logicize]

Yes, but Harvard shows:<br /><br />0.00108 au or 161,565.84 kilometers<br />

 

[MeteorWayne]

2007 VK184 2506488.39 2150 June 6.89 0.01620 AU <br /><br />It is only the 73rd closest approach.<br /><br />From:<br />http://cfa-www.harvard.edu/iau/lists/PHACloseApp.html<br /><br />"The distances quoted are from the nominal orbit solutions in the cited references and can be quite uncertain, particularly for one-opposition objects." <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]

BTW it may not be obvious to you, but each source uses their own code for both orbit calculation, as well as differing leves of precision for accounting for all the other mass in the solar system.<br /><br />For instance jpl uses<br /><br /> planetary ephem. DE405 <br /> SB-pert. ephem. SB405-CPV-2 <br /> quality code 5 <br /> fit RMS .42023 <br /> data source ORB <br /> producer Otto Matic <br /> solution date 2008-Jan-11 11:44:10 <br /><br />NEO Dys makes the impact probability highest in 2048, JPL in 2050, on the next orbit.<br /><br />there's still plenty of uncertainlty <img src="/images/icons/smile.gif" /><br /> <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]

2008 AF4 now has 75 observational datapoints in the analysis, up from 50 (according to Hohmantransfer). No change in trajectory or threat assessment. <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>