From pluto at projectpluto.com Tue Apr 6 19:57:01 2021 From: pluto at projectpluto.com (Bill Gray) Date: Tue, 6 Apr 2021 19:57:01 -0400 Subject: [neo_followup] A10whno = mag 11.5 rock : light curve? Message-ID: <119bbeae-09ff-9c18-b53d-6cfba71eb848@projectpluto.com> Hello all, Just thought I'd note that this is about as bright as they get. Seems like a good light-curve opportunity. The ephemeris uncertainty should be small, a few arcminutes or so. (Be warned that MPC appears to be off by over a degree, due to the absence of earth/moon perturbations.) Further commentary at https://www.projectpluto.com/temp/mpec.htm It was brought to my attention by Peter Birtwhistle, who was unable to find it... because it went through the earth's shadow for a bit. I wish we'd realized that before it reached the shadow; Peter has observed such events before... http://www.minorplanet.info/MPB/issues/MPB_45-3.pdf ...and gotten interesting results. I'd have liked to see the light curve from this bright object as it went through the shadow, and to have compared observed photometry to computed magnitudes from Find_Orb. -- Bill From peter at birtwhistle.org.uk Tue Apr 6 20:10:43 2021 From: peter at birtwhistle.org.uk (Peter Birtwhistle) Date: Wed, 7 Apr 2021 01:10:43 +0100 Subject: [neo_followup] {MPML} A10whno = mag 11.5 rock : light curve? In-Reply-To: <119bbeae-09ff-9c18-b53d-6cfba71eb848@projectpluto.com> References: <119bbeae-09ff-9c18-b53d-6cfba71eb848@projectpluto.com> Message-ID: <6b4472db-3225-088f-ece1-04d59da48fe8@birtwhistle.org.uk> Hi Bill, I was aware of when it was coming out of shadow from a FindOrb ephemeris and was waiting for it to appear, but nothing came out. Since then I've searched all around and several degrees down the line FindOrb indicates the uncertainty lies, but still found nothing unfortunately. Peter On 07/04/2021 00:57, Bill J. Gray wrote: > Hello all, > > ?? Just thought I'd note that this is about as bright as they > get.? Seems like a good light-curve opportunity.? The ephemeris > uncertainty should be small,? a few arcminutes or so.? (Be > warned that MPC appears to be off by over a degree,? due to > the absence of earth/moon perturbations.) > > ?? Further commentary at > > https://www.projectpluto.com/temp/mpec.htm > > ?? It was brought to my attention by Peter Birtwhistle,? who > was unable to find it... because it went through the earth's > shadow for a bit.? I wish we'd realized that before it > reached the shadow;? Peter has observed such events before... > > http://www.minorplanet.info/MPB/issues/MPB_45-3.pdf > > ?? ...and gotten interesting results.? I'd have liked to see > the light curve from this bright object as it went through > the shadow,? and to have compared observed photometry to > computed magnitudes from Find_Orb. > > -- Bill > > > -=-=-=-=-=-=-=-=-=-=-=- > Groups.io Links: You receive all messages sent to this group. > View/Reply Online (#36362): https://groups.io/g/mpml/message/36362 > Mute This Topic: https://groups.io/mt/81904528/1447918 > -=-=- > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Posts to this list or information found within may be freely used, > with the stipulation that MPML and the originating author are cited as > the source of the information. > -=-=- > Group Owner: mpml+owner at groups.io > Unsubscribe: https://groups.io/g/mpml/unsub [peter at birtwhistle.org.uk] > -=-=-=-=-=-=-=-=-=-=-=- > > > . From pluto at projectpluto.com Tue Apr 6 20:16:23 2021 From: pluto at projectpluto.com (Bill Gray) Date: Tue, 6 Apr 2021 20:16:23 -0400 Subject: [neo_followup] {MPML} A10whno = mag 11.5 rock : light curve? In-Reply-To: <6b4472db-3225-088f-ece1-04d59da48fe8@birtwhistle.org.uk> References: <119bbeae-09ff-9c18-b53d-6cfba71eb848@projectpluto.com> <6b4472db-3225-088f-ece1-04d59da48fe8@birtwhistle.org.uk> Message-ID: <15c5f924-37d2-8240-ee8d-278ec7abbc49@projectpluto.com> Hi Peter, all, Sorry... figured it out shortly after sending those messages. Please ignore this object. The follow-up observations must be of something else; the original ATLAS data lines up passably well with a bit of space junk. I expect it'll be off as 'not a minor planet' shortly. -- Bill On 4/6/21 8:10 PM, Peter Birtwhistle wrote: > Hi Bill, > > I was aware of when it was coming out of shadow from a FindOrb ephemeris and was waiting for it to appear, but nothing came out. > > Since then I've searched all around and several degrees down the line FindOrb indicates the uncertainty lies, but still found nothing unfortunately. > > Peter > > > > On 07/04/2021 00:57, Bill J. Gray wrote: >> Hello all, >> >> ?? Just thought I'd note that this is about as bright as they >> get.? Seems like a good light-curve opportunity.? The ephemeris >> uncertainty should be small,? a few arcminutes or so.? (Be >> warned that MPC appears to be off by over a degree,? due to >> the absence of earth/moon perturbations.) >> >> ?? Further commentary at >> >> https://www.projectpluto.com/temp/mpec.htm >> >> ?? It was brought to my attention by Peter Birtwhistle,? who >> was unable to find it... because it went through the earth's >> shadow for a bit.? I wish we'd realized that before it >> reached the shadow;? Peter has observed such events before... >> >> http://www.minorplanet.info/MPB/issues/MPB_45-3.pdf >> >> ?? ...and gotten interesting results.? I'd have liked to see >> the light curve from this bright object as it went through >> the shadow,? and to have compared observed photometry to >> computed magnitudes from Find_Orb. >> >> -- Bill >> >> >> -=-=-=-=-=-=-=-=-=-=-=- >> Groups.io Links: You receive all messages sent to this group. >> View/Reply Online (#36362): https://groups.io/g/mpml/message/36362 >> Mute This Topic: https://groups.io/mt/81904528/1447918 >> -=-=- >> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >> >> Posts to this list or information found within may be freely used, with the stipulation that MPML and the originating author are cited as the source of the information. >> -=-=- >> Group Owner: mpml+owner at groups.io >> Unsubscribe: https://groups.io/g/mpml/unsub [peter at birtwhistle.org.uk] >> -=-=-=-=-=-=-=-=-=-=-=- >> >> >> . > From planetaryscience at yahoo.com Tue Apr 6 20:38:37 2021 From: planetaryscience at yahoo.com (Sam Deen) Date: Wed, 7 Apr 2021 00:38:37 +0000 (UTC) Subject: [neo_followup] {MPML} A10whno = mag 11.5 rock : light curve? In-Reply-To: <6b4472db-3225-088f-ece1-04d59da48fe8@birtwhistle.org.uk> References: <119bbeae-09ff-9c18-b53d-6cfba71eb848@projectpluto.com> <6b4472db-3225-088f-ece1-04d59da48fe8@birtwhistle.org.uk> Message-ID: <254966785.174892.1617755917243@mail.yahoo.com> A10whno was just removed from the NEOCP as "not a minor planet" ... ~Sam On Tuesday, April 6, 2021, 5:37:49 PM PDT, Peter Birtwhistle wrote: Hi Bill, I was aware of when it was coming out of shadow from a FindOrb ephemeris and was waiting for it to appear, but nothing came out. Since then I've searched all around and several degrees down the line FindOrb indicates the uncertainty lies, but still found nothing unfortunately. Peter On 07/04/2021 00:57, Bill J. Gray wrote: > Hello all, > > ?? Just thought I'd note that this is about as bright as they > get.? Seems like a good light-curve opportunity.? The ephemeris > uncertainty should be small,? a few arcminutes or so.? (Be > warned that MPC appears to be off by over a degree,? due to > the absence of earth/moon perturbations.) > > ?? Further commentary at > > https://www.projectpluto.com/temp/mpec.htm > > ?? It was brought to my attention by Peter Birtwhistle,? who > was unable to find it... because it went through the earth's > shadow for a bit.? I wish we'd realized that before it > reached the shadow;? Peter has observed such events before... > > http://www.minorplanet.info/MPB/issues/MPB_45-3.pdf > > ?? ...and gotten interesting results.? I'd have liked to see > the light curve from this bright object as it went through > the shadow,? and to have compared observed photometry to > computed magnitudes from Find_Orb. > > -- Bill > > > -=-=-=-=-=-=-=-=-=-=-=- > Groups.io Links: You receive all messages sent to this group. > View/Reply Online (#36362): https://groups.io/g/mpml/message/36362 > Mute This Topic: https://groups.io/mt/81904528/1447918 > -=-=- > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > > Posts to this list or information found within may be freely used, > with the stipulation that MPML and the originating author are cited as > the source of the information. > -=-=- > Group Owner: mpml+owner at groups.io > Unsubscribe: https://groups.io/g/mpml/unsub [peter at birtwhistle.org.uk] > -=-=-=-=-=-=-=-=-=-=-=- > > > . -- neo_followup mailing list neo_followup at projectpluto.com http://projectpluto.com/mailman/listinfo/neo_followup_projectpluto.com -------------- next part -------------- An HTML attachment was scrubbed... URL: From planetaryscience at yahoo.com Fri Apr 16 20:17:40 2021 From: planetaryscience at yahoo.com (Sam Deen) Date: Sat, 17 Apr 2021 00:17:40 +0000 (UTC) Subject: [neo_followup] Followup request for 14F2601 = possible very small, low-q comet in Southern hemisphere References: <335042541.3233497.1618618660270.ref@mail.yahoo.com> Message-ID: <335042541.3233497.1618618660270@mail.yahoo.com> Hi all, Although currently 0.3 AU from Earth, I think this technically constitutes an NEO followup as 1) the objects MOID to Earth may be less than 0.1 AU, and 2) it's currently moving rapidly at 8 "/min and seems likely to peak at 15 "/min in a few days, so catching it soon is important. 14F2601 was found earlier today (or yesterday, for the Europeans/Asians) and having been recovered by 2 different other observatories, the orbit seems quite robust. Based on 8 hours of observation so far, it seems to have a very eccentric orbit (the minimum aphelion CNEOS's stat ranging gives among 1000 clones is ~3.9 AU, and the second lowest is ~4.9 AU - and that's completely ignoring all e>1 clones. So we, quite literally, >99.8% surely have a Jupiter-crosser on our hands.) What makes this object arguably much more interesting is that it's quite small - H around 20 to 22. There are only a handful of distant asteroids with Q>10 AU dimmer than H=20, exactly 5 to be specific. And for a generous assumed slope of 20 (M1 = 20.0 in this case), there are precisely 3 known comets beyond Q>10 AU. No matter how you slice it, this object is rather unique. Anyway in terms of observation, the object is currently in the far southern hemisphere with a declination of -47 and getting lower. It should be relatively accessible to some folks here at magnitude 19-20. The biggest limiting factor is its quick motion and rapidly increasing uncertainty, which as of your reading this is most likely over 100", and will be over 1000" in only a day. So time is very much of the essence here! Here are geocentric ephemerides assuming e=1.0 for anyone who wants to try at it (don't worry about individual observatories, right now the uncertainty is much bigger than any parallax effects): #Geocentric Date (UTC) HH:MM?? RA????????????? Dec???????? delta?? r???? elong? mag? '/hr??? PA?? " sig PA ---- -- -- -----? -------------?? -----------? ------ ------ -----? --- ------ ------ ---- --- 2021 04 17 00:00? 11 52 04.166?? -47 54 19.84? .24126 1.1896 136.2 19.8?? 8.50 249.6?? 112? 68 2021 04 17 00:30? 11 51 40.359?? -47 55 48.56? .24093 1.1892 136.1 19.8?? 8.52 249.7?? 119? 68 2021 04 17 01:00? 11 51 16.466?? -47 57 17.19? .24060 1.1888 136.0 19.8?? 8.54 249.8?? 126? 68 2021 04 17 01:30? 11 50 52.488?? -47 58 45.72? .24028 1.1884 136.0 19.8?? 8.56 249.9?? 132? 68 2021 04 17 02:00? 11 50 28.424?? -48 00 14.15? .23995 1.1879 135.9 19.8?? 8.59 249.9?? 139? 69 2021 04 17 02:30? 11 50 04.273?? -48 01 42.49? .23963 1.1875 135.8 19.8?? 8.61 250.0?? 147? 69 2021 04 17 03:00? 11 49 40.036?? -48 03 10.73? .23930 1.1871 135.8 19.8?? 8.63 250.1?? 154? 69 2021 04 17 03:30? 11 49 15.713?? -48 04 38.86? .23898 1.1867 135.7 19.8?? 8.65 250.2?? 162? 69 2021 04 17 04:00? 11 48 51.302?? -48 06 06.88? .23866 1.1863 135.7 19.8?? 8.68 250.3?? 170? 69 2021 04 17 04:30? 11 48 26.804?? -48 07 34.80? .23833 1.1859 135.6 19.8?? 8.70 250.3?? 178? 69 2021 04 17 05:00? 11 48 02.218?? -48 09 02.61? .23801 1.1855 135.5 19.8?? 8.72 250.4?? 186? 69 2021 04 17 05:30? 11 47 37.543?? -48 10 30.30? .23769 1.1850 135.5 19.8?? 8.74 250.5?? 194? 69 2021 04 17 06:00? 11 47 12.781?? -48 11 57.87? .23737 1.1846 135.4 19.8?? 8.77 250.6?? 203? 69 2021 04 17 06:30? 11 46 47.930?? -48 13 25.33? .23705 1.1842 135.3 19.8?? 8.79 250.6?? 212? 69 2021 04 17 07:00? 11 46 22.990?? -48 14 52.66? .23673 1.1838 135.3 19.8?? 8.81 250.7?? 221? 70 2021 04 17 07:30? 11 45 57.960?? -48 16 19.87? .23640 1.1834 135.2 19.8?? 8.84 250.8?? 230? 70 2021 04 17 08:00? 11 45 32.841?? -48 17 46.96? .23608 1.1830 135.1 19.8?? 8.86 250.9?? 240? 70 2021 04 17 08:30? 11 45 07.632?? -48 19 13.91? .23577 1.1825 135.1 19.8?? 8.88 251.0?? 250? 70 2021 04 17 09:00? 11 44 42.333?? -48 20 40.73? .23545 1.1821 135.0 19.8?? 8.90 251.1?? 260? 70 2021 04 17 09:30? 11 44 16.943?? -48 22 07.42? .23513 1.1817 134.9 19.8?? 8.93 251.1?? 270? 70 2021 04 17 10:00? 11 43 51.463?? -48 23 33.97? .23481 1.1813 134.9 19.7?? 8.95 251.2?? 280? 70 2021 04 17 10:30? 11 43 25.891?? -48 25 00.38? .23449 1.1809 134.8 19.7?? 8.97 251.3?? 291? 70 2021 04 17 11:00? 11 43 00.228?? -48 26 26.64? .23417 1.1805 134.7 19.7?? 9.00 251.4?? 301? 70 2021 04 17 11:30? 11 42 34.473?? -48 27 52.76? .23386 1.1800 134.6 19.7?? 9.02 251.5?? 312? 70 Best of luck to anyone trying to recover it. It seems you might need it. ~Sam -------------- next part -------------- An HTML attachment was scrubbed... URL: