Comments on NEOCP objects

Last updated 2014 Nov 30 13:35 UT

Following are comments and pseudo-MPECs on objects of particular interest currently on the NEOCP. "Interesting" usually means unusual orbits, or coming close to the earth or other planets, or artificial satellites, or radar targets, or in serious need of observation (usually because the ephemeris uncertainty is climbing rapidly), or other reasons I'll make up as I go along. I'm trying to keep these arranged so that the objects most urgently in need of observation are at the top of the page.

When objects are no longer in need of observing, I'll move them down to the 'previously noted on this page' section.

A couple of notes: I'll update this pretty frequently, as is necessary given the pace at which NEOCP is updated, but it won't be totally in sync, of course. I usually check NEOCP in the (East Coast US) morning, about 13:00 UT, then again throughout the day every now and then until about 02:00 UT.

Also, note that astrometry from NEOCP is not supposed to be redistributed; that's why it is (mostly) "redacted" (shown in black). CSS has kindly given permission to have their data redistributed; that's why (G96) and (703) data is not redacted. If you're willing to have your data appear in these pseudo-MPECs, please e-mail me at plüto@p⃗röj̄‮moc.ôtulptce‬ (after removing diacritical marks intended to confuse spammers).

Finally, when I say something would be a good Arecibo or Goldstone target, I mean "if they get time on the telescope, the signal/noise ratio would be good". Both radar telescopes get lots of uses for other purposes, and spend some time getting repaired as well.

• VW8BF39 A good Arecibo target on 6-8 December, and a good Goldstone target on 8-9 December.

Previously noted on this page :

• VW87344 An excellent target for both Arecibo and Goldstone over the coming weeks. It's already quite good for Arecibo, and will get there for Goldstone by about 29 November. Perigee should be at about one earth-moon distance, plus or minus 1%, on Dec 8.0 +/- .2. Like VW83625 = 2014 WU200, this has an unusually low encounter speed relative to us, and may be a good space mission candidate.

• VW83B7A (Now MPECed as 2014 WC201) An excellent target for both Arecibo and Goldstone, on December 2 and (for Goldstone) a day or two around that.

• VW83625 (Now MPECed as 2014 WU200) This will pass within about 440000 +/- 20000 km within a day or so of 10 December. It should be a really good Arecibo target around then, and a decent to spectacular Goldstone target for about a week. On top of all that, it has a rather low encounter velocity (about 2 km/s). It's a good candidate (thus far, anyway) to be a space mission target.

• VW1919A (Now MPECed as 2014 WY119) A good radar target for Arecibo over the next few days, and a barely passable one for Goldstone over much of the next week.

• P10fQO2 (Now MPECed as C/2014 W2 PANSTARRS) Looks to be in a nearly parabolic orbit with q=2.673 +/- 0.002. I'd expect it to turn out to be really parabolic, except that it has MOID=0.0936 with respect to Jupiter, and it's acquired a lot of observations without getting designated as a comet. So maybe it's been slowed down by Jupiter just enough to have a period of a few centuries, and to get the gasses baked off it.

• P10fTqq (Now MPECed as C/2014 W4 PANSTARRS) An object in an unusual, sort-of-Centaurish orbit (q=4.23, Q=9.1, and a close MOID=0.135 AU with Jupiter). Might turn out to be a comet.

• VW125E9 This will be an excellent target from Arecibo over the next day or two, and a decent one from Goldstone.

• P10fB7a A rather large (H=20.3, so around a few hundred meters in diameter) object. Starting next Tuesday, Arecibo could get it with SNR/day of about 80 for a week. It really doesn't need any follow-up until next week, though; right now, perhaps because it's around magnitude 16.8, it's getting more astrometry than it really needs. (A light-curve just good enough to determine a period would be a wonderful thing, though. The intensity of radar detections depends greatly on the rotation period, but we don't usually know that in advance of radar observing.)

• TVP8SAZ This PanSTARRS find is either a cometary object about an AU or so away, or a TNO at least 32 AU away. I'm leaning toward the latter. If it's actually close by, one of the three observatories reporting data for it is getting much worse data than usual. But it still could be nearby if there's some really bad astrometry in the mix.

• PTF0N2 = 1963-039C Since removed as "not a minor planet". This is Vela-1B, a now nearly ancient spacecraft (I assume defunct after 51 years!) that detected gamma rays to get early warning of a nuclear attack.

Previously noted on this page :

• MAS216 (Now MPECed as 2014 UR116) This is a rather large (H=19.9) NEO (Earth MOID=0.0222), crossing the orbits of Venus and Mars with small MOIDs for them as well. Looks like a nice find for MASTER.

• VUA9933 (Now designated as 2014 UT114) This one is probably a Centaur. It has to be between 14.4 and 28.5 AU away from us; anything else either leads to a very hyperbolic orbit, or to horrible residuals. It's probably around 17 AU away, unless it's in a comet-like or retrograde orbit. Both would be pretty interesting, and we can always hope, but a Centaur looks most likely. It'll probably be a while before we have enough data to say. For the nonce, I've just gone with the best-fitting circular orbit, currently around a=18.3. MPC, on the other hand, has gone with a Väisälä orbit with perihelion distance 16.87 AU; that puts the aphelion at 45.2 AU.

Previously noted on this page :

• VUA831E Looks to be in an highly eccentric orbit that will bring it close to us (under a million km), but still a lot of uncertainty. Observations are required pretty urgently; you can see that the ephemeris uncertainty climbs a lot over the next few hours. Be warned: those last three observations look a little bit raggedy, and may be misleading me into thinking this object is more "interesting" than it really is. If it's truly a comet approaching close to us, it's an excellent radar target.

• VT39862 (Now MPECed as 2014 TG64) A Centaur with what looks like a rather unstable orbit. It has a Jupiter MOID of 0.43 AU, and a Saturn one of 0.14 AU. It's hard to imagine that lasting very long... then again, its period of 60 years is about twice that of Saturn and five times that of Jupiter. Maybe it's getting some sort of resonant stability.

• VU3C140 (now MPECed as 2014 UR) The Delta-V for this object is about 4.3 km/s, which might be within ARM range. The orbital period is just shy of one year, meaning we might get further close approaches. (Edit: with further data, it looks like an easy recovery next October at mag 18, and slightly more difficult at mag 21.2 in October 2016.) It's also a good radar target from both Arecibo and Goldstone over the next few days. Follow-up would be a good idea.

• VT9EE6C Should pass within about 140000 km, but with huge uncertainties at present.

• VS92A15 (Now MPECed as 2014 SC324) This will come within 440000 +/- 60000 km on 22 October. It will be an excellent radar target for both Goldstone and Arecibo, and will reach mag 13 during the flyby.

• VT2EF95 A good radar target from Arecibo and Goldstone on October 5.

• VT2FA7D This passed within 98000 +/- 500 km of the earth at about 16:00 UT on October 1. It came from an elongation of about ten degrees from the Sun, and was therefore not found until it was already about half a million km past us.

• VS29F15 (Now MPECed as 2014 SF304) A really good target for Arecibo and Goldstone, especially on 4 October, but really anytime from now to the 6th or 8th.

• VS8EF96 Really good for Arecibo on September 28 and 29th (and not too bad on the 27th or 30th). Goldstone would also have a good shot at it on those days.

• VS225B8 An excellent target for Arecibo on September 25, again on the 27th. Goldstone would have a good shot at it on the 26th and 27th (UT).

• VS8BE7F An excellent target for Goldstone on September 23, and not bad on the previous day.

• VR87DC9 Yet another good potential radar target for both Arecibo and Goldstone, on September 6 and 7.

• VQ8034D = 2014 QC391 This should be an excellent radar target for both Arecibo (September 5, 6, 7, and maybe 8), and Goldstone (September 4 and 5), given some more astrometry (and luck with scheduling on short notice).

• VR1A6E2 = 2014 RA This flew by us at close range (56660 +/- 40 km). Unfortunately, it wasn't spotted until it was about as far away as the moon.

• OGS8791 This has somewhat low velocity relative to the earth (about 2.5 km/s, depending on how you compute it) and a possible close fly-by in 2030. So it could be of interest as a spacecraft target. More astrometry could confirm or deny this.

• P10dRif = 2014 QY33 Should be a good Arecibo target, especially on 30 August. It'll need some astrometry, though.

• N006vz6 = 2014 PP69 Another tiny, distant comet, i=93, q=1.24 AU. However, the period looks to be about fifty years; I'm reasonably sure it's not parabolic.

• P10dBni = 2014 QU2 Retrograde comet (i=125). My orbit assumes it's parabolic, which should be a pretty safe bet. It's been MPECed with an e=0.85, P=55 year orbit, but I find this hard to believe; I still think further observations will prove it to be parabolic.

• P10d5UL = 2014 OF300 Good for both Arecibo and Goldstone, starting around 6 August.

• P10cN7T = 2014 OW3 A good Arecibo target, and a passable Goldstone target, in late July. More astrometry would be a Good Thing. Good photometry, and maybe a rotation period, would probably be a big help.

This has H=22.3 (about 150 meters in diameter) and a MOID of a mere 0.0012 AU, so it's of greater interest than your average rock.

• P10crOp A decent Arecibo target in mid-July.

• VM13C83 Yet another retrograde (i=165), probably parabolic or near-parabolic object, q=2.44 or so. We seem to be getting a run of these...

• P10ciez Almost certainly retrograde. The pseudo-MPEC has assumed a parabolic orbit as well, putting perihelion a bit past Jupiter.

• VM13E83 (Now MPECed as 2014 MJ26) Just barely a decent Arecibo radar target, on 5 and 6, maybe 7 July.

• VM13AD7 (Now MPECed as 2014 MV18) Looks like a really good Arecibo radar target, and maybe a decent Goldstone target.

• VMBDD6C Almost certainly parabolic or near-parabolic. The perihelion is probably somewhere around the orbit of Jupiter, but could be quite a bit closer or further away. More astrometry in a couple of days would really help.

• VMBCF21 (Now MPECed as 2014 MH6) We caught this one outward-bound. It passed within 247100 +/- 300 km of us on June 22, and is rapidly getting fainter.

• VM131A6 (Now MPECed as 2014 MY17) (Update: This object was recovered at (958) Observatoire de Dax, over a degree from its nominal position. That put the orbit out at the far end of the expected region; it won't be a radar target after all.) The ephemeris uncertainty on this object is currently about 15', growing to two degrees over the next day, so quick follow-up would be most welcome. It could turn out to be a decent Arecibo target sometime near 10:00 UT on 26 June, which is another reason I'd really like to see it get some astrometry.

• VLB8A04 (Now designated C/2014 L5) Looks like a distant retrograde comet. The ephemerides should be good for a long time, but it would be good to follow it up in a week or two; that ought to make its orbit clear enough for MPEC-ing.

• N006op2 (Update: This has been removed from NEOCP as a 'Does Not Exist' object... %$*!@ it; it looked really interesting.) This is quite possibly in a very earth-like orbit. At H=24, it's rather large for space junk. There is a decent probability that it will come in close enough for radar observations. It should be a high-priority target.

• P10bWBj An interesting PHA, with H=18 or so. (It doesn't pose any immediate "hazard"; it's gone past us and is headed away from us.) With e=0.85 +/- 0.03, it might be a comet. It looks to have a long enough period (seven or eight years) to have evaded detection until now.

The ephemeris uncertainty should be low for quite a while, but it wouldn't hurt to get some more data in a few days.

• VLB8133: This passed within 220000 +/- 35000 km of us on 3 June, about 60% of the distance to the moon. It's conceivable that it will get further confirmation over the next day or so, though it's dropping in magnitude as it goes away.

• VKB2811: This passed within 344500 +/- 500 km of us on 27 May. It's getting faint rather quickly. By the time the ephemeris uncertainty gets large enough to make it worthwhile to image it, it'll be too faint to image. So there's no real point in going after it; its orbit is as good as it's going to be.

• VK0C557: Should be a good radar target for Arecibo around 05:00 UT on 29 May... about two hours after I write this. Long odds, but one may always hope.

• P10bJ5W: This is based on a mere four observations from (F51) PanSTARRs, unfortunately reported late enough that the object was already lost. This passed within 25000 +/- 6000 km of the earth, and probably passed through the earth's shadow (though if it's a sigma or two off nominal, it could have missed). Far too faint to be observed now. At H=31.5, this object was probably less than a meter across.

• VJ04F1F: Should be a really good radar target starting around 5:00 UT on 7 May for Arecibo and Goldstone. (Though probably too close; it comes within a mere 107000 km, less than a third of the distance to the moon, and that would really call for a bistatic setup.)

• N006dzv: I should probably mumble about this one, as I've been burned by NEOWISE astrometry before... but this looks as if it could be a faint comet passing close by us in a month or so, and could be a good Arecibo target (they don't often get a chance to ping comets). More astrometry should tell us if this is just wishful thinking on my part.

• 2014 HO132: This got removed rather quickly from NEOCP. It's a good radar target from Arecibo and Goldstone.

• VHA2B9D: This object will be a good Arecibo radar target on 1 May and an excellent one the next day. It'll be pretty good from Goldstone on 2 May as well. As usual, it will need astrometry for either telescope to find it. It'll pass us at 286000 +/- 15000 km on 3 May. (It doesn't come near the moon. I always check that for objects coming within one lunar distance in hopes of finding impacts, but so far, I've yet to find anything that even came close to the moon.)

• N0060MG: (since MPECed as 2014 HQ124) This NEOWISE find will pass within about 0.008 AU on 8 June, and will be an absolutely stupendous radar target from Arecibo and Goldstone. The former should get SNR/day of about four million.

• VHA066F: This looks to be a Centaur, with a=9.5 +/- 1.2 AU, around that of Saturn. With a four-day arc and at a distance of about 4.5 AU, its position is well-determined. It should probably be re-observed sometime around 10 May, when its ephemeris uncertainty will have grown to a dozen arcseconds or so, but it won't have gotten too faint to find easily.

• VH9F4A6: About 8 AU away right now, and it's probably a comet (nominal q=7 +/- 1 AU, e=.6 +/- .2). It could turn out to be a Centaur. It won't need observing for a month or so. It's only getting brighter, and (as is usually the case for such distant objects) its ephemeris uncertainty will remain low.

• VH3F68D: (Now MPECed as 2014 HM4)

This would be a really good radar target from Arecibo around 21:00 UT on the 25th, and a decent target on the next two days. (That despite the fact that they're actually running on half-power at present; those SNRs should be cut by two... but an SNR/day of 20,000 is still really good.) It would also be a reasonable target for Goldstone on the 25th. It needs some astrometry pretty soon, though, and more leading up to the actual observing windows. (Update: Arecibo should be able to go for it, but not Goldstone.)

• VH9E639: (Now MPECed as 2014 HV2)

This will come within about a half million km of us around the 30th, and may be a pretty good Goldstone target. (The ephemeris uncertainty near perigee is currently huge, and may push it too far south to be a Goldstone target. Or might push it to where Arecibo could get in on the fun, too.) Astrometry every few days between now and then would be a Good Thing.

• VH3D0EB: (Now MPECed as 2014 HO2)

I briefly had hopes this might turn out to be in a somewhat earthlike orbit, with low relative velocity with respect to us, and with the sort of size desired for ARRM targets. It's not. I was fooled by some slightly "off" astrometry. The new orbit shows that the ephemeris uncertainty is low, but the object is receding and getting fainter; astrometry in the next day or two would be a good idea, before it becomes unobservable.

• VH9C8A0: (Now MPECed as 2014 HW)

Should be a decent Arecibo radar target near 05:00 UT on 21 and 22 April, but Arecibo won't be able to schedule it. It's a passable target from Goldstone on the 25th; I've switched over to displaying ephems for Goldstone along with the usual geocentric ephemerides. It'll need more astrometry between now and then, though there is no danger of losing it.

• VH3D3EA: (Now MPECed as 2014 HP2)

This is passing within about 0.009 AU of us. It's currently quite bright, with only modest positional uncertainty (but enough so that another observation or two would really help the orbit). By the 25th, its brightness will start dropping as it goes to lower elongations.

• VH9C417: (Now MPECed as 2014 HL2)

Earth MOID=0.0008, and is still somewhat uncertain. Some more astrometry should rule out the possibility of impacts. However, this could easily wait until 25 April; the object's uncertainty is mere arcseconds, and any impacts are certainly not imminent. So it's not a really high-priority object right now.

• P10aSVM: Three observations from (F51) PanSTARRS on 10 April, plus six from (291) Spacewatch, and they don't appear to link together. I'm pretty sure there are two different objects here.

• VH9DAD4, VH9DB57: (Now designated 2014 HZ2 and 2014 HA3, respectively) Both look to be Hungarias with q=1.6 or so, and are not likely to be NEOs. Both have ephemerides will be within an arcminute for a week or so, and are getting slightly brighter and better placed. Somebody should take a look at both sometime around new moon, but going after them before then would be pretty much wasted effort.

• VH3C2B9: (Now MPECed as 2014 HM2)

Over-observed. Definitely an NEO (q=1.092 +/- .001), but its current ephemeris uncertainty is tiny, and it's bright. Give it another look sometime around new moon; its ephemeris uncertainty will be about a quarter arcminute by then.

• VH3D7A6: (Now designated 2014 HA1) Maybe even more over-observed, and it's not very interesting (q=1.801 +/- .001, i=31, e=.31). It'll probably get linked to a known object. If not, it'll be easy enough to find at the next lunation. Let it go.

• VH9C3FD: (Update: Lost now, unfortunately. It passed within a mere 200000 km on 22 April, and is now down at tiny elongations, though still on NEOCP at mag 33!) This will be a fairly good target for Goldstone on 21 and 22 April, with the latter looking somewhat better (SNR/day=300 or so). As usual, it will need more astrometry between now and then. As I write this, the ephemeris uncertainty is climbing; I'm hoping somebody gets it soon.

• VG9BCEE: (Now MPECed as 2014 GG49) This object would be a great radar target from Arecibo and a decent one from Goldstone. Mike Nolan tells me that unfortunately, it's not a good fit for Arecibo's schedule. Good news is that Lance Benner thinks Goldstone should be able to get it. It's best placed for observing from Goldstone on the 18th, 19th, and 20th (as the ephemeris in the pseudo-MPEC shows). However, the ephemeris uncertainty will be about a quarter arcminute by then, so a few more observations would be a Really Good Idea.

• P10aTaU: This one has a poorly defined orbit at present, but looks to be a retrograde object in a near-parabolic orbit with perihelion near 4.7 AU. (The nominal orbit has e=.55 +/- .18, but anything like that would be quite weird; I'm assuming parabolic or close to it.) If you look at the "sig" column in the ephemerides in the pseudo-MPEC, though, you'll see that its position is known to within a dozen arcseconds or so over the next week. So it's not really a priority for observing.

• VG3AFFC: (Now MPECed as 2014 GY48) This is (edit: was) a bit of a surprise: it's at H=18.4, a big rock that should have turned up long ago. It has an orbital period a little over two years, though, and it looks as if it passed close by at far southern declinations in late April 2012. My guess is that before that, it kept coming to perihelion at times when we were somewhere else, but we'll need more data before we can say such things with any degree of confidence; the orbit gets quite raggedy when you project it back before the 2012 encounter. It'll be interesting to see how it avoided detection all these years. I expect we'll know after it's been tracked for a week or two. (The orbit is still not great, but it looks as if it's managed to dodge us, being either too far south or too far away at each perihelion.)

It should be a decent Arecibo target in early May. (The pseudo-MPEC shows Arecibo opportunities, best on May 3, 4, and 5, maybe on the 6th. For an object to be observed at Arecibo, it has to be at altitude +70.5 or better as seen from Arecibo, and closer to the zenith is better. Usual disclaimer: the fact that an object would be a good radar target is no guarantee that the radar team will get time on the telescope, or that the telescope will be in full working order when the time comes.)

There is no danger of the object being lost, but the ephemeris uncertainty for early May is currently about 90 arcseconds. So some observations sometime around 20 April, plus a few a week or so later, will be needed.

• VG97A66: (Now MPECed as 2014 GB49) This object was found within about 0.01 AU of us, and actually has a decent (U=7.8) orbit. However, it's dropped to mag 23.4, and will get no further observations.

• VG97D19: (Now MPECed as 2014 GC49) Sort of the same thing, except this object passed within 113600 +/- 160 km of us on 2014 April 3. It's now down to mag 25.

• P10aTfi: This looked quite a bit like an object zipping by on a near-parabolic orbit. However, with further data, MPC got a link to 2010 JP14.