Newly discovered asteroids closely approaching earth.

[MeteorWayne]

2009 WJ6, discovered yesterday passed within 0.5 Lunar Distances about 4 hours ago. It's small, 8-19 meters in size.

It's currently on the JPL risk page with 3 potential impacts between 2042 and 2056, cumulative PS = -5.40.

 

[MeteorWayne]

Small asteroid (10-23 meters diameter) 2009 WV 51 was discovered yesterday and will pass within 0.4 LD tomorrow at 19:53 UT. It is not on the risk page.

 

[MeteorWayne]

Wanted to mention 2009 XR1 before it fell off the lists. A very small asteroid (4-8 meter diameter) Discovered Dec 11th, with close approach at 2.0 LD on Dec 15th. Look how small we are catching now, at ~8 LD distance.

 

[MeteorWayne]

Had to expand it to 3 LD, since 2010 AG30 shows up in articles about 2010 AL30

2010 AG30 close approach 2.7 LD Jan 14th. Not on the risk list. 11-24 meters in diameter (the same estimated size as 2010 AL30; H=27.0).

2010 AF40 close approach 2.3 LD Jan 21. This currently has a microscopic chance of impact, with the 3 events between 2018 and 2063. PS is -8.25...that REALLLY low risk 26-59 meters. The cumulative risk of impact for all 3 is 1 in 625 million

Just a hint as to how things work... on the JPL risk page they only list one value for the diameter, not the range; in the case of 2010 AF40 they list 34 meters. So the range is 26-59, the risk page lists only 34. Just stuff to keep in mind for the future.

 

[MeteorWayne]

It's been a while, just noticed 2010 CK19, a very small asteroid (7-16 m) in a near circular 375 day orbit passed 0.9 lunar distance from earth earlier today. It was discovered on the 14th.

http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2 ... ;cad=1#cad

 

[MeteorWayne]

2010 DJ1 (11-25 meters) discovered Feb 17th, passed 1.0 LD from earth 4 hours ago.

 

[a_lost_packet_]

Do your sources normally list velocity with these objects? Just curious as to how fast many of these objects are traveling.

 

[MeteorWayne]

Yes they do:

http://neo.jpl.nasa.gov/ca/

2010 DJ1 is at the bottom of the "recent close approaches" section at the top. The velocity listed is relative to the earth. 19.98 km/sec is pretty fast compared to most, I once did a histogram of the speeds but, that's on that melted hard drive in the corner. That's due to it's highly elliptical orbit with perihelion in the outer asteroid belt (3.77 AU). It's actual speed at earth's orbital distance is probably about 40 km/sec; it's in a prograde orbit so that lowers the speed relative to us. I'd calculate the actual speed at 1 AU, but not until coffee input :lol: Have to find the formula.

Here's the 2010 DJ1 sbdb page (with close approaches)


http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2 ... ;cad=1#cad

Wayne

 

[a_lost_packet_]

Yes they do:

http://neo.jpl.nasa.gov/ca/

Sweet. Thanks!

I'd calculate the actual speed at 1 AU, but not until coffee input :lol: Have to find the formula.

I'll wait... (jk)

Here's the 2010 DJ1 sbdb page (with close approaches)


http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2 ... ;cad=1#cad

Wayne

Nice!

Too bad about that histogram you calc'd! It'd be very interesting. I was wondering if there was a way to predict how much energy was represented by these objects, sort of a comparison chart with ratings on it showing threat levels if a potential impact was realized. Why? Well, for starters, people don't realize how many "close approaches" there are and, while the Dinosaur Killer still lingers in people's minds, they don't realize the potential of smaller impactors. A chart (or an app that could receive a database) showing the "kilitons" of damage potential orbiting in our solar system might be eye-opening. If there were, say, a diagram showing 50 red blips of "close approaches", each averaging 100x the destructive power of Hiroshima, maybe people could related to it better.

There are too few people trying to watch over us in the case of a potential impactor.

 

[MeteorWayne]

Just FYI, the impact energy is calculated for objects on the risk page. Not really needed for close approaches if they aren't an impact threat.

The only problem is the impact energy isn't shown in the list,

http://neo.jpl.nasa.gov/risk/

only for each individual object such as this:

http://neo.jpl.nasa.gov/risk/a153814.html

Object 153814 2001 WN5

Energy 1.7e+04 MT

 

[a_lost_packet_]

Just FYI, the impact energy is calculated for objects on the risk page. Not really needed for close approaches if they aren't an impact threat.

The only problem is the impact energy isn't shown in the list,

http://neo.jpl.nasa.gov/risk/

only for each individual object such as this:

http://neo.jpl.nasa.gov/risk/a153814.html

Object 153814 2001 WN5

Energy 1.7e+04 MT

Woot! Thanks! That helps. Now, I just have to figure out how to visually present the information in a way that communicates it effectively to the uninitiated.

 

[MeteorWayne]

Yeah, to get that you really have to go through object by objects. It's actually OK, since only the top 5 or ten have greater than 1 in 50,000 chances of impact.

 

[MeteorWayne]

2010 FU9 (12-26 m) was discovered March 20, 2 days after closest approach at 1.5 LD on March 18th.

It is not on the Sentry risk page.

 

[MeteorWayne]

Small (17-38m) asteroids 2010 GA6 was discovered April 9th and passed 1.1 Lunar Distance from earth April 9th. It was briefly on the Sentry risk page, but has been removed.

 

[MeteorWayne]

2010 JA passed 1.8 LD from earth earlier this morning. It's small (11-24 m), was discovered May 4, and is not on the risk list for the next century.

MW

 

[MeteorWayne]

3 small newbies, 1 very small, one very close:

2010 JL88
12-26 meters diameter
Discovered May 15
Close Approach, 1.0 x Lunar Distance May 17
VERY VERY VERY VERY low risk of impact from 2059-2058 (cumulative PS -6.97)

2010 KQ
5-12 m
Disc 5/16
CA 1.3 LD 5/21
VERY VERY low impact risk in 2037 (Cumulative PS -5.03)

2010 KO10
11-26m
Disc 5/20
CA 0.5 LD May 23
No impact risk in the next century

MW

 

[silylene]

This new thread "New large earth impact crater found - Eocene impact cluster!" may be of interest to those who like this subject:
http://www.space.com/common/forums/viewtopic.php?f=26&t=24390

 

[MeteorWayne]

2010 KK37 discovered 5/23, 2 days after close approach at 2.0 X Lunar Distance; 21-47 meters diameter. Not on risk list.

 

[MeteorWayne]

2010 KV39: 12-27 meters, dicovered 5/24, close approach 5/26 at 0.7 LD. It is currently on the risk page with PS -6.23 cumulative, -6.72 max for 29 VI's between 2037-2101.

However it has a VERY short observational arc of only half a day.

MW

 

[MeteorWayne]

A small asteroid 2010 NN (6-13m) was discovered 3 days after close approach at 1.4 LD on July 3, based on 11 obs on July 6-7. It came from the sun side of earth.

It's also on the Sentry risk page with a cumulative PS of -6.42 for 63 potential impacts beginning in 2049.

 

[silylene]

An interesting paper on hazardous asteroid 1999 RQ36 , which has about a 1 in 1500 chance of hitting the earth, most likely in 2182. It is perhaps the most hazardous asteroid known. Observations in 2011 and 2018 will help greatly to refine the future orbit further and to help paramaterize the impact of the Yarkowsky effect. If these future observations show that a collision is likely, according to the paper, a deflection mission would need to be launched in 2060, when 1999 RQ36 passes through a 'keyhole'. If we wait til after 2060, then it will be very difficult to deflect. An impact from this 560m diameter object would have the energy of 2700 MT.

http://arxiv.org/abs/0901.3631
pdf of full paper: http://arxiv.org/pdf/0901.3631v2

radar image:

 

[MeteorWayne]

After a 3 month drought, 3 new ones.

2010 RB12, discovered Sept 2 made close approach at 2.5x Lunar Distance Sept 4th. Size 11-25 meters. Not on the risk page.

2010 RX30 discovered Sept 5, closest approach Sept 8th at 0.6 LD (247,777 km, 154,961 miles) Size 10-22 m, not on the risk page. Short arc, 43 obs over 1 day.

Edited, it is now on the risk page for 10 potential impacts between 2038 and 2080. PS -4.08.
2010 RX30 sbdb page

Finally (thanx for the heads up Emily Lakdawalla and EarthlingX) 2010 RF12, discovered Sept 5, closest approach Sept 8 at 21:18 UTC +/- 7 minutes, at 0.2 LD (79,525 km, 49,414 miles).... ....Size 6-14 m. It is on the Sentry risk page with Palermo Scale -5.11 for 30 potential impacts between 2058 and 2110. Very short observational arc, only a day with 46 observations.
2010 RF12 sbdb page
I will refine the distances as more observations come in.

MW

 

[MeteorWayne]

New observations have been added, so the following refinements for these two objects.

2010 RF12, now 83 observations. Close approach distance: 79,391 +/- 80 km (49,332 +/- 51 miles). CA time 21:12 UTC Sept 8 +/- < 1 minute (9:12 PM EDT). Risk update, PS -3.67 for 54 potential impacts from 2095-2110.

2010 RX30, now 56 observations, CA distance: 247,739 +/- 338 km (153,938 +/- 210 miles). CA time 09:51 UTC Sept 8 +/- < 1 minute (5:51 AM EDT). Risk update, PS -4.28 for 9 potential impacts from 2063-2103.

 

[silylene]

On 2010 RF12, JPL now listing it as PS = -3.67 cum (2.2% chance of collision!), while NEODyS has removed it from the danger list. It is rare the two simulations disagree to this degree. The object is very small, this may be the reason why (NeoDys figures it would burn up anyways with no damage?).

 

[MeteorWayne]

On 2010 RF12, JPL now listing it as PS = -3.67 cum (2.2% chance of collision!), while NEODyS has removed it from the danger list. It is rare the two simulations disagree to this degree. The object is very small, this may be the reason why (NeoDys figures it would burn up anyways with no damage?).

Nope, here's why, from NEODyS:

"In this page we list all the asteroids for which possible impact solutions, compatible with the existing observations and in a time span from nowadays till 2080, are known, although we are now extending our monitoring to 2090"

All the potential JPL Sentry Impactors are from 2095 to 2110, outside of the NEODyS calculations.

MW