Risky asteroid 2010 JU39

[MeteorWayne]

I've been watching this one for a few days, but the latest obs have increased the risk to the level where we usually start a dedicated thread.

2010 JU39 ~ 439 meters in size is TS 1, and the Palermo scale risk is up to -1.61 cumulative, with a -1.87 PS for an impact in 2058 (1 in 77,000).

It was discovered May 9, and has 28 observations over 7.1 days. There are 66 Virtual Impactors (all of this from the JPL Sentry site) from 2035 to 2109.

It's still a short arc, with huge error bars, but worth watching for the entertainment value.

MW

 

[Cleomedes]

A question:

For the date 2058-06-26.38 this asteroid is currently listed as having a distance (rEarth) of 0.04. What does that distance equate to in kilometres? Is it about 0.25 km or have I got the wrong end of the proverbial measuring stick?

 

[MeteorWayne]

A question:

For the date 2058-06-26.38 this asteroid is currently listed as having a distance (rEarth) of 0.04. What does that distance equate to in kilometres? Is it about 0.25 km or have I got the wrong end of the proverbial measuring stick?

Welcome to Space.com

The distance of close approach is expressed in AU (Astronomical Units, the average earth-sun distance) so

0.0449102493061871 Au = 6,718,477.6684 kilometer

That's about 17.5 times the distance from the earth to the moon.

 

[silylene]

Cheers! i know I shouldn't be happy we have a new TS1 asteroid to watch, but it is fun.

 

[ainu7]

Hi all~

This asteroid seems like having 2-dimensional error bar, so it's nominal distance is nearer than previous asteroids with same level of risk. i.e, if prob is 1/10000, then it usually had very long (like 1AU) but thin uncertainty line, but this time that line is some kind of 0.1AU long and 10 earth radii thick. - so near miss is more likely than usual.

So for next few days prob will go/down very rapidly since error bar of each dimension will shrink.

I'm recently tweaking observation data from neodys, by weighting more reliable observatories' data. Seems like this asteroid is good chance to test my experiment.

 

[robnissen]

Cheers! i know I shouldn't be happy we have a new TS1 asteroid to watch, but it is fun.

I agree completely. I always get excited on the few occasions when further observations INCREASES the probability of impact. And I am then disappointed when the probabilty of impact eventually recedes to zero. Logically, my reaction should be the exact opposite, seeing as how there is that whole destroying-all-life-as-we-know-it thingy going on. But for some odd reason, I am always rooting for the impact.

 

[MeteorWayne]

ainu7,
I wouldn't go through too much effort yet unless you have time to kill. Right now the uncertainties are so high that JPL Sentry and NEODyS have 2011 and 2012 as the next close apparoach...a year apart (that's the along orbit uncertainty speaking). From previous experience watching the evolution, I'd wait until there's at least a two week arc before spending too much time examining the possibilies.

However, if it's fun or educational for you, go for it and share your results!

Wayne

 

[MeteorWayne]

With new observations, the orbit has been refined, and this object was removed from the JPL Sentry risk page today.
MW