asteroid 2009 KK: Risk in May,Jun 2009

[silylene]

EDIT BY METEOR WAYNE: I am bumping this thread just to make it easier to find on Sept 23rd 2009. This shows how we at SDC followed the development of the impact risk of this object from it's discovery until the risk reached zero and it was removed from the JPL Sentry and NEODyS risk lists. It's purpose was to show the process of the risk increasing, then decreasing to zero as more observations came in and were absorbed. It's probably got far too much detail for the casual reader, but now that we are folloing 2009 SG18, I thought I'd bump it. This took place During May and June this year.
Meteor Wayne

On asteroid 2009KK, we only have a few days of arc so far, but this NEO looks interesting. I have been following this daily, and the newer arc data from yesterday and today has so far doubled the risk. Usually, the risk rapidly diminishes as new data excludes a possibility of collision.

Still, don't get worried. The arc is still very short (3 days) which means big error bars, and the risk is still not that high. However, this will be a fun asteroid to watch as we get more data.


from NASA NEO:
2009 KK Analysis based on
47 observations spanning 2.9157 days (2009-May-17.25987 to 2009-May-20.17558)
Diameter: 0.277 km
Vimpact: 18.92 km/s
Energy: 1.2e+03 MT
Cumulative probability: 1 in 28,000 chance
Highest Risk date: 2022-05-29.79
Palermo Scale: -1.68 cumulative, -1.89 on 2022-05-29.79
Torino Scale: 0 (I think they want a longer arc before changing this to '1')
http://neo.jpl.nasa.gov/risk/2009kk.html

JPL NEODyS ranks this similarly: Palermo Scale: -1.68 cumulative, -1.90

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Thanx, silylene.

There is only a single Torino scale 1 object so far:

2007 VK184, with possible impacts from 2048-2057. Impact risk is 4 3.4e-04. Impact velocity 15.63 km/sec. Size ~ 130 meters.

Torino Scale descriptions...

No Hazard
(White Zone) 0 The likelihood of a collision is zero, or is so low as to be effectively zero. Also applies to small objects such as meteors and bodies that burn up in the atmosphere as well as infrequent meteorite falls that rarely cause damage.


Normal
(Green Zone) 1 A routine discovery in which a pass near the Earth is predicted that poses no unusual level of danger. Current calculations show the chance of collision is extremely unlikely with no cause for public attention or public concern. New telescopic observations very likely will lead to re-assignment to Level 0.

Meriting Attention by Astronomers

(Yellow Zone) 2 A discovery, which may become routine with expanded searches, of an object making a somewhat close but not highly unusual pass near the Earth. While meriting attention by astronomers, there is no cause for public attention or public concern as an actual collision is very unlikely. New telescopic observations very likely will lead to re-assignment to Level 0.

3 A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of localized destruction. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.

4 A close encounter, meriting attention by astronomers. Current calculations give a 1% or greater chance of collision capable of regional devastation. Most likely, new telescopic observations will lead to re-assignment to Level 0. Attention by public and by public officials is merited if the encounter is less than a decade away.


Threatening (Orange Zone)

5 A close encounter posing a serious, but still uncertain threat of regional devastation. Critical attention by astronomers is needed to determine conclusively whether or not a collision will occur. If the encounter is less than a decade away, governmental contingency planning may be warranted.

6 A close encounter by a large object posing a serious but still uncertain threat of a global catastrophe. Critical attention by astronomers is needed to determine conclusively whether or not a collision will occur. If the encounter is less than three decades away, governmental contingency planning may be warranted.

7 A very close encounter by a large object, which if occurring this century, poses an unprecedented but still uncertain threat of a global catastrophe. For such a threat in this century, international contingency planning is warranted, especially to determine urgently and conclusively whether or not a collision will occur.

Certain Collisions
(Red Zone)

8 A collision is certain, capable of causing localized destruction for an impact over land or possibly a tsunami if close offshore. Such events occur on average between once per 50 years and once per several 1000 years.

9 A collision is certain, capable of causing unprecedented regional devastation for a land impact or the threat of a major tsunami for an ocean impact. Such events occur on average between once per 10,000 years and once per 100,000 years.

10 A collision is certain, capable of causing global climatic catastrophe that may threaten the future of civilization as we know it, whether impacting land or ocean. Such events occur on average once per 100,000 years, or less often.

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

More observations, higher odds. It is now a Torino Scale 1

2009 KK
Potential impacts:2022-2049
Impact Odds:9 3.7e-05
Impact velocity:15.55
Estimated size: 270 meters
PAlermo Scale: -1.58 Total, -1.65 2022 impact possibility
Torino Scale: 1

Here's the small body database page for this object:

http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2009+KK;orb=1

And the Risk page from Sentry:

http://neo.jpl.nasa.gov/risk/2009kk.html

 

[silylene]

Re: asteroid 2009 KK May 29 2022

This is unusual, that new observational data is increasing the assessed risk !

NEODyS also gives almost the same analysis and Palermo Scale rating, although they are still keeping the Torino Scale = 0 .

The risk in 2022 is still low, just 1/34,000 (1/27,000 cumulative). In addition to May 29, 2022, there is also a close pass in 2026 with a rather high risk.

Let's keep watching this asteroid!

 

[silylene]

Re: asteroid 2009 KK May 29 2022

Another day of observational data, and the collsion risk is very slightly increased again. NEODyS is now also Torino Scale 1.

2009 KK Analysis based on
62 observations spanning 4.8779 days
Diameter: 0.271 km
Vimpact: 19.14 km/s
Energy: 1.2e+03 MT
Cumulative probability: 1 in 26,000 chance
Highest Risk date: 2022-05-29.77
Palermo Scale: -1.57 cumulative, -1.63 on 2022-05-29.79
Torino Scale: 1

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Only 3 more observations, but more importantly separated by a few days. The odds have decreased slightly.

Analysis based on
65 observations spanning 5.8695 days
(2009-May-17.25987 to 2009-May-23.12933)

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.66 (5/29/2022)
Palermo Scale (cumulative) -1.64
Impact Probability (cumulative) 3.3e-05
Number of Potential Impacts 6

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Just to demonstrate risk vs likely, the risk date of 5/29/22 is when the plane of the asteroid's orbit crosses that of the earth's.

Using the Ephemeris (which uses all the multibody calculations) the closest approach will in fact be about 1200 UT on April 22, 2022. The May 29 date is the worst case scenario if the orbital speed is way off. That's why the odds are so low. The odds are the closest approach will be on April 22nd, at ~ 0.72 AU, or no closer than Mercury ever gets to us.

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

More observations, longer arc, higher risk....

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.50
Palermo Scale (cumulative) -1.49
Impact Probability (cumulative) 4.6e-05
Number of Potential Impacts 5 (2022-2038)

Analysis based on
68 observations spanning 6.9541 days
(2009-May-17.25987 to 2009-May-24.21401)

EDIT:
I'm adding this data block to preserve the calculations as of the time that these numbers were generated.

Orbit Determination Parameters # obs. used (total) 68
data-arc span 7 days
first obs. used 2009-05-17
last obs. used 2009-05-24
planetary ephem. DE405
SB-pert. ephem. SB405-CPV-2
quality code 8
fit RMS .42659
data source ORB
producer Otto Matic
solution date 2009-May-25 00:50:08

Additional Information Earth MOID = .000773083 AU
T_jup = 4.373

Vimpact 19.14 km/s
Vinfinity 15.56 km/s
H 20.5
Diameter 0.270 km
Mass 2.6e+10 kg
Energy 1.1e+03 MT

e .4550555028646509 0.0035959
a 1.50214204302493 0.0080185 AU
q .8185840402620865 0.0010391 AU
i 18.21094610016857 0.12598 deg
node 68.24906713724904 0.084221 deg
peri 247.1958735119685 0.026824 deg
M 322.2605798227323 0.35036 deg
tp 2455041.994892401827
(2009-Jul-29.49489241) 0.090627 JED
period 672.457635688431 d
1.84 yr
5.3844 d
0.01474 yr
Q 2.185700045787774 0.011667 AU

I'll explain these in more detail later. Please feel free to ignore for now, I'm just using this thread as a documented notepad.
MW

--------------------

Just for example compare with Apophis, 2004 MN4 (Torino Scale zero; same size as 2009 KK but a slower approach speed)

Torino Scale (maximum) 0
Palermo Scale (maximum) -2.42
Palermo Scale (cumulative) -2.41
Impact Probability (cumulative) 2.3e-05
Number of Potential Impacts 3 (2036,2037,2069)

Analysis based on 2 radar delay, 5 Doppler, and
731 optical observations spanning 884.52 days
(2004-Mar-15.10789 to 2006-Aug-16.626954)

-------------------

And the other Torino scale 1 object, 2007 VK184, half the size, but nearly identical approach speed to 2009 KK)

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.83
Palermo Scale (cumulative) -1.82
Impact Probability (cumulative) 3.4e-04
Number of Potential Impacts 4 (2048-2057)

Analysis based on
101 observations spanning 60.013 days
(2007-Nov-12.13904 to 2008-Jan-11.15189)

 

[silylene]

Re: asteroid 2009 KK May 29 2022

2009 KK is really becoming an interesting object. MW, how long will this object continue to be viewable for observational data?

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

2009 KK is really becoming an interesting object. MW, how long will this object continue to be viewable for observational data?

I would think at least through the end of the year. The closest approach isn't till mid June, and it is favorably placed after that. It will be within 0.5 AU through November. In late July, it appears it will be passing just outside the earth's orbit.

Nearest to close approach we will get to measure it's orbital speed very accurately since it will be passing us on the outside (night sky), whereas now the measurements are kind of looking upstream at the path (leaving lots of uncertainty of the orbital velocity).

By the end of July, the uncertainty should be VERY small. By then we should know what the future holds in some detail.

EDT: I must correct myself. My perception that it would pass outside earth was incorrect; I was fooled by the 3D perspective. In fact, in July it will be on the sun side of our obit, below the sun from our perspective, but still invisible (due to closeness to sun, and "new asteroid" view (like in a new moon, it will be backlit from our view). When I have more time I'll look at it in more detail.

Wayne

 

[silylene]

Re: asteroid 2009 KK May 29 2022

Thanks MW. It is good to know we should have a very long observational arc on this object.

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Two new observations have been entered, extending the arc to 9 days, though they have not propogated to the risk page yet. I suspect they will decrease the odds of a 2022 impact.

The detailed "Horizon's" Ephemeris has increased the nominal close approach distance in 2022 from 0.47 AU to 0.56 AU.
Also the RMS error on the solution has decreased very slightly.

I assume the risk calculations on the Sentry main page take a bit longer to process.

Data Blocks:

e .4546624980746366 0.0025399
a 1.500998750318944 0.0056503 AU
q .8185509088920251 0.00073514 AU
i 18.20157040233956 0.089185 deg
node 68.25612401395688 0.059648 deg
peri 247.2224837751274 0.018083 deg
M 322.2022359576847 0.24737 deg
tp 2455042.023284668555
(2009-Jul-29.52328467) 0.063688 JED
period 671.6900622020142 d 1.84 y +/-3.7927 d 0.01038 y
Q 2.183446591745862 0.0082192 AU

# obs. used (total) 70
data-arc span 9 days
first obs. used 2009-05-17
last obs. used 2009-05-26
planetary ephem. DE405
SB-pert. ephem. SB405-CPV-2
quality code 8
fit RMS .44551
data source ORB
producer Otto Matic
solution date 2009-May-26 00:50:09

Additional Information Earth MOID = .000784082 AU
T_jup = 4.375

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

OK, the new obs have trickled down..

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.58
Palermo Scale (cumulative) -1.58
Impact Probability (cumulative) 3.7e-05
Number of Potential Impacts 4 (2022-2038)

Analysis based on
70 observations spanning 8.8622 days
(2009-May-17.25987 to 2009-May-26.12204)

Vimpact 19.14 km/s
Vinfinity 15.56 km/s
H 20.5
Diameter 0.270 km
Mass 2.6e+10 kg
Energy 1.1e+03 MT

 

[silylene]

Re: asteroid 2009 KK May 29 2022

MW, you were right, the risk was decreased slightly. We need more arc data!

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Don't have time to post detail right now, on my way to give a meteor talk to a high school science class. 3 more obs, slight reduction on RMS error, no significant change to 2022 close approach so probably only a tiny change (if any) to the palermo scale and impact probabilities when it propogates down to the risk page.

More later

MW

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

OK, back from teaching my astronomy class, that was a blast. I even spoke about this asteroid

Data has propogated down the the risk page. Now only the 2022 May 29 ~ 14:16 PM EDT (18:16 UT) impact only. Very slight decrease in odds

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.60
Palermo Scale (cumulative) -1.60
Impact Probability (cumulative) 3.6e-05
Number of Potential Impacts 1

Analysis based on
73 observations spanning 8.9603 days
(2009-May-17.25987 to 2009-May-26.22015)

Vimpact 19.14 km/s
Vinfinity 15.56 km/s
H 20.5
Diameter 0.270 km
Mass 2.5e+10 kg
Energy 1.1e+03 MT
all above are mean values
weighted by impact probability

e .4548123227558623 0.0021864
a 1.50133100036516 0.0048686 AU
q .8185071608636992 0.00063154 AU
i 18.20683142544734 0.076823 deg
node 68.25261038021945 0.051397 deg
peri 247.2232797041817 0.015159 deg
M 322.216745802122 0.213 deg
tp 2455042.019620197639
(2009-Jul-29.51962020) 0.054794 JED
period 671.9130951027463
1.84 3.2683
0.008948 d
yr
n .5357835747269521 0.0026062 deg/d
Q 2.184154839866621 0.0070828 AU

# obs. used (total) 73
data-arc span 9 days
first obs. used 2009-05-17
last obs. used 2009-05-26
planetary ephem. DE405
SB-pert. ephem. SB405-CPV-2
quality code 8
fit RMS .43661
data source ORB
producer Otto Matic
solution date 2009-May-27 00:50:09

Additional Information Earth MOID = .000780274 AU
T_jup = 4.375

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Two more obs, RMS has increased and close approach in 2022 has decreased to 0.2102 AU (May 3). Also note decreased MOID. I suspect risk will be higher on today's update.

e .4549448835618698 0.0021499
a 1.501614310241135 0.0047908 AU
q .8184625627136445 0.00062033 AU
i 18.21168308810472 0.075533 deg
node 68.24941888295062 0.050542 deg
peri 247.2251563739472 0.014937 deg
M 322.2287330090252 0.2095 deg
tp 2455042.017202772877
(2009-Jul-29.51720278) 0.053942 JED
period 672.1032949279036
1.84 3.2164
0.008806 d
yr
n .5356319522858717 0.0025633 deg/d
Q 2.184766057768626 0.0069703 AU


Orbit Determination Parameters # obs. used (total) 75
data-arc span 9 days
first obs. used 2009-05-17
last obs. used 2009-05-26
planetary ephem. DE405
SB-pert. ephem. SB405-CPV-2
quality code 8
fit RMS .45407
data source ORB
producer Otto Matic
solution date 2009-May-28 00:50:06

Additional Information Earth MOID = .000776832 AU
T_jup = 4.374

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Wow, took a long time to trickle down to the risk page, but as I suspected a slight increase in risk.



Torino Scale (maximum) 1
Palermo Scale (maximum) -1.56
Palermo Scale (cumulative) -1.56
Impact Probability (cumulative) 3.8e-05
Number of Potential Impacts 4 (back to 2022-2038)

Analysis based on
75 observations spanning 8.9603 days
(2009-May-17.25987 to 2009-May-26.22015

Vimpact 19.14 km/s
Vinfinity 15.56 km/s
H 20.5
Diameter 0.270 km
Mass 2.6e+10 kg
Energy 1.1e+03 MT
all above are mean values
weighted by impact probability

 

[silylene]

Re: asteroid 2009 KK May 29 2022

MW, thanks. This object remains very interesting (and entertaining to my curiosity!)

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Oh, and if I'm reading my ephemeris right, it will be even more interesting today. There are now 83 observations, and the CA (Close Approach) of the nominal orbit in 2022 has dropped from 0.510 AU to 0.3569 AU. A very slight increase in the RMS value, and a decrease in the MOID (Mean Orbital Intersection Distance to .000747539 AU. Also the CA date in 2022 has moved from 5/3 closer to the danger date of the 29th, CA is now on May 10 2022.

I suspect there will be a pretty big increase in risk in today's update.

# obs. used (total) 83
data-arc span 11 days
first obs. used 2009-05-17
last obs. used 2009-05-28
planetary ephem. DE405
SB-pert. ephem. SB405-CPV-2
quality code 8
fit RMS .45623
data source ORB
producer Otto Matic
solution date 2009-May-29 00:50:11

Additional Information Earth MOID = .000747539 AU
T_jup = 4.370

e .4558513201467818 0.0016767
a 1.503545633364212 0.003758 AU
q .8181523714942067 0.00047801 AU
i 18.24504009663175 0.05884 deg
node 68.22729607483383 0.039408 deg
peri 247.2390321063707 0.010332 deg
M 322.8448205848242 0.16189 deg
tp 2455042.000864937082
(2009-Jul-29.50086494) 0.042421 JED
period 673.4003649335132
1.84 2.5247
0.006912 d
yr
n .5346002448863297 0.0020043 deg/d
Q 2.188938895234217 0.0054711 AU

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

Looks like I'm right. NEODyS is reporting a Palermo Scale for the 2022 impact at -1.40 with impact probablity of 5.67e-5.

This is using all 83 visual obs.

 

[xXTheOneRavenXx]

Re: asteroid 2009 KK May 29 2022

After so many observations, what is the current estimates in size/mass MeteorWayne?

 

[MeteorWayne]

Re: asteroid 2009 KK May 29 2022

After so many observations, what is the current estimates in size/mass MeteorWayne?

From a few posts back, here are the latest estimates:

Diameter 0.270 km
Mass 2.6e+10 kg


Of course, they are just estimates, based on an assumed albedo. Both could be off by a considerable amount. The diameter range would be from about 210-470 meters, and depending on composition the mass estimate could be off by a factor of 10. That means the impact energy could be off by a factor of 5

The Sentry page has just been updated:

Torino Scale (maximum) 1
Palermo Scale (maximum) -1.40
Palermo Scale (cumulative) -1.40
Impact Probability (cumulative) 5.7e-05
Number of Potential Impacts 1 (18:16 UT May 29, 2022) That is almost exactly 13 years from now.

Analysis based on
83 observations spanning 11.027 days
(2009-May-17.25987 to 2009-May-28.28729)

Vimpact 19.14 km/s
Vinfinity 15.57 km/s
H 20.5
Diameter 0.270 km
Mass 2.6e+10 kg
Energy 1.1e+03 MT
all above are mean values
weighted by impact probability

This is now the lighest risk known PHA (Potentially Hazardous Asteroid), 10 times the risk of Apophis, and with an impact much sooner.

Compare the above with Apophis (2004 MN4)
Torino Scale (maximum) 0
Palermo Scale (maximum) -2.42
Palermo Scale (cumulative) -2.41
Impact Probability (cumulative) 2.3e-05
Number of Potential Impacts 3 (April 13, 2036-2069)

Vimpact 12.59 km/s
Vinfinity 5.87 km/s
H 19.7
Diameter 0.270 km
Mass 2.7e+10 kg
Energy 5.1e+02 MT

 

[silylene]

Re: asteroid 2009 KK May 29 2022

It is very unusual that the odds for an object remain this high as we gain additional observational data. many thousands of asteroids have been tracked, and almost always as we gain more observational data, the odds of collision diminish to zero very quickly. Let's keep watching !

 

[silylene]

Re: asteroid 2009 KK May 29 2022

Newest NEODyS data is further increasing the risk again, the highest now of any known object with a solution less than 100 years from today.

new Palermo Scale = -1.31
arc length = 12 days, 86 observations
dat: 2022-05-29.761 single solution