Asteroid 2004 BL86

January 21, 2015 2:51 AM

Asteroid 2004 BL86 will safely pass about three times the distance to the moon on January 26. It will not be bright enough to view with an unaided eye; however, astronomy sites including Earthsky and Universe Today have instructions for amateur astronomers with suitable equipment.

The JPL News article contains more information on the planned scientific observations and NASA's Near Earth Object Program. They also remind us that " [t]he flyby of 2004 BL86 will be the closest by any known space rock this large until asteroid 1999 AN10 flies past Earth in 2027. "

posted by tykky (10 comments total)

Only 3 LD? Meh. There have been much closer approaches just today. Keep an eye on the JPL Near Earth Object Close Approach page. I don't even understand why 2004 BL86 is getting any attention, when just today 2015 BC is making a close approach at 1.6 LD, and 2015 BP is at 1.8 LD. These aren't huge asteroids, smaller objects generally get discovered very close to Earth, as is obvious from their labels as being discovered in 2015. There have been much closer approaches recently, here's a list of them from 2014. IMHO it's not really a close approach unless it's within 1 LD. This is not a big deal unless you see a close approach rated > 1 on the Torino Scale.
posted by charlie don't surf at 11:00 AM on January 21, 2015

AT this point in our history, we really, really should be grabbing these floating rocks and mining the shit out of them and building all kinds of cool stuff in orbit so we don't have to build it on the ground anymore.
posted by bartonlong at 11:10 AM on January 21, 2015

I don't even understand why 2004 BL86 is getting any attention

It's not the closest asteroid on the chart, but it's one of the larger ones there. Using diameter / distance as a metric of "excitingness", 2004 BL86 is over 5x as big-close as the next most "exciting" asteroid on the list (which, FWIW, is 2002 FG7).

We're not going to get clobbered by it, but it might be fun to point some telescopes at it and watch it whiz by!
posted by aubilenon at 11:42 AM on January 21, 2015 [1 favorite]

The exciting asteroids are the ones that escape detection until they enter the atmosphere, like Chelyabinsk. I figure you're more likely to die from one of these meteors, than from some major extinction event asteroid strike.

Anyway, I was just surprised because I spend a lot of time doing calculations via the JPL ephemerides and looking at the NEO site, and this did not even register as newsworthy to me. I will have to look closer, maybe I can become a profitable prophet of doom.
posted by charlie don't surf at 12:22 PM on January 21, 2015 [1 favorite]

I posted this more for the amateur astronomer angle than asteroid impact extinction-event angle. Maybe the latter is a good topic for another FPP? We need to reclaim the spacerock tag, that's for sure.
posted by tykky at 1:05 PM on January 21, 2015

The extinction event angle is always present in stories like this.

I read the linked articles and it looks like it will be a struggle to locate the asteroid, let alone track it. Oh well, what do I know? I haven't owned a telescope in years, technology has come a long ways since then.

I recall previous close approaches that were covered live with streaming video from observatories. High end telescope video of the asteroid was much less impressive than the computer graphic simulation of the view of Earth from the asteroid. Actually the POV was right behind the asteroid, so you could see it looming down over the Earth. I hope we will see some observatories streaming this flyby, and if I find any, I will post in this thread.
posted by charlie don't surf at 1:23 PM on January 21, 2015

Though the big boys denied this, I feel Chelyabinsk rode into town on the coattails of a big rock passing, hours before. I think large asteriods have a pull of their own and can push ahead or pull smaller pieces to the edge of our gravity, then the smaller item comes down, and the larger goes on its way.
posted by Oyéah at 2:34 PM on January 21, 2015

another regular reminder of how much stuff there is flying around up there is @lowflyingrocks, whose bio is "I mention every near earth object that passes within 0.2AU of Earth. @tomtaylor made me."

(yeah, 0.2AU isn't particularly close.)
posted by russm at 5:19 PM on January 21, 2015 [1 favorite]

instructions for amateur astronomers with suitable equipment

C'mon, what we need is open-source 3d printed designs for asteroid killers you can launch from your backyard.

Chelyabinsk rode into town on the coattails of a big rock passing, hours before

All objects in the solar system are exerting gravitational pull on all other objects, all the time. The thing is that it's quite possible that any of them is getting too close and gets its orbit perturbed enough that it comes our way, but the key is that this perturbation can happen anywhere -- and most of that is going to happen someplace out in the Oort cloud, where there are a LOT of rocks. The mathematics of orbital mechanics and Kepler's Law are pretty brutal -- once something is oriented so it's going to hit something else, it's nigh-well inevitable, even if that orientation takes place years or decades earlier.

Now relax.
posted by dhartung at 6:29 PM on January 21, 2015

The asteroid has a small moon. There are first radar images at JPL News.
posted by tykky at 4:36 AM on January 27, 2015 [1 favorite]