2011 BT15 Goldstone Radar Observations Planning
2011 BT15 was discovered by Pan-STARRS (Haleakala, HI) on January 24, 2011. It has an absolute magnitude of 21.7, suggesting a diameter within a factor of two of 140 meters, but nothing else is known about its physical properties. This object will be too faint for optical observations until early January of 2014, when it should reach visual magnitude 17 and be a good target for lightcurves and BVRI colors. 2011 BT15 makes regular close approaches within 0.1 AU of both Earth and Mars. The closest approach during this apparition will occur at 0.032 AU (~ 12.5 lunar distances) on December 28, when this asteroid should be a moderately strong radar target at Goldstone. At the time of the closest approach, it will be too far south for Arecibo to track, but after Jan. 4 it will move north into Arecibo's declination range and become a strong imaging target. This object is on NASA's "NHATS" list of potential human mission targets. As a result, physical observations are particularly important. 2011 BT15 has been classified as a "Potentially Hazardous Asteroid" (PHA) by the IAU's Minor Planet Center.
Orbital and Physical Characteristics orbit type Apollo semimajor axis 1.297 AU eccentricity 0.304 inclination 1.7 deg perihelion distance 0.903 AU aphelion distance 1.691 AU absolute magnitude (H) 21.7 diameter 140 m (+/- a factor of two) rotation period unknown pole direction unknown lightcurve amplitude unknown spectral class unknown Future Close-approaches: Date (CT) Body CA Dist MinDist MaxDist Vrel TCA3Sg Nsigs P_i/p ---------------------- ----- ------- ------- ------- ------ ------ ------ ------- A.D. 2013 Dec 28.64804 Earth .032226 .032223 .032229 6.000 1.14 34564. .000000 A.D. 2016 Sep 15.39071 Earth .050851 .050849 .050853 8.171 0.43 80852. .000000 A.D. 2034 Dec 30.43280 Mars .088653 .088645 .088661 7.598 0.38 40270. .000000 A.D. 2038 Dec 28.62563 Earth .034507 .034495 .034518 5.948 5.23 10605. .000000 A.D. 2056 Feb 14.63544 Mars .038894 .038876 .038912 6.197 3.28 2.86E5 .000000 A.D. 2060 Dec 25.61175 Earth .043404 .043325 .043483 5.754 41.06 8778.7 .000000 A.D. 2069 Apr 03.87949 Mars .074414 .074377 .074450 5.012 13.56 2.22E5 .000000 A.D. 2082 Sep 24.04659 Earth .031911 .031790 .032034 6.427 74.75 78747. .000000 A.D. 2102 Jan 07.68721 Earth .009398 .007487 .011289 7.230 385.89 3268.4 .000000 A.D. 2104 Oct 26.62162 Earth .080565 .071032 .093075 5.559 26244. 2.18E5 .000000 NOTE: post-epoch CA list was truncated due to Earth TCA3Sg exceeding the set limit. Last update: 2013 Dec 16
M.P.E.C. 2011-B43 Issued 2011 Jan. 27, 05:20 UT The Minor Planet Electronic Circulars contain information on unusual minor planets and routine data on comets. They are published on behalf of Commission 20 of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A. Prepared using the Tamkin Foundation Computer Network MPC@CFA.HARVARD.EDU URL http://www.minorplanetcenter.org/iau/mpc.html ISSN 1523-6714 2011 BT15 Observations: K11B15T* C2011 01 24.28933 01 49 25.905+11 35 47.92 22.1 wLEB043F51 K11B15T C2011 01 24.29437 01 49 27.985+11 36 01.94 21.8 wLEB043F51 K11B15T C2011 01 24.29932 01 49 29.981+11 36 15.38 22.2 wLEB043F51 K11B15T %C2011 01 25.31754 01 56 37.39 +12 23 07.7 21.0 RoEB043F65 K11B15T tC2011 01 26.11773 02 02 16.53 +12 59 26.4 21.1 VoEB043291 K11B15T tC2011 01 26.12153 02 02 18.08 +12 59 37.4 21.9 VoEB043291 K11B15T tC2011 01 26.14194 02 02 26.61 +13 00 32.0 22.1 VoEB043291 K11B15T tC2011 01 26.14966 02 02 29.80 +13 00 52.8 oEB043291 K11B15T tC2011 01 27.17027 02 09 43.77 +13 46 36.0 21.5 VoEB043291 K11B15T tC2011 01 27.17399 02 09 45.25 +13 46 45.7 21.5 VoEB043291 Observer details: 291 LPL/Spacewatch II. Observer T. H. Bressi. 1.8-m f/2.7 reflector + CCD. F51 Pan-STARRS 1, Haleakala. Observers N. Primak, A. Schultz, S. Watters, J. Thiel, T. Goggia. Measurer PS1 Science Consortium. 1.8-m Ritchey-Chretien + CCD. F65 Haleakala-Faulkes Telescope North. Observer T. Lister. 2.0-m f/10 Ritchey-Chretien + CCD. Orbital elements: 2011 BT15 PHA, Earth MOID = 0.0013 AU Epoch 2011 Feb. 8.0 TT = JDT 2455600.5 MPC M 36.48821 (2000.0) P Q n 0.63120667 Peri. 309.74665 +0.57676209 -0.81638539 a 1.3459275 Node 105.00619 +0.75848382 +0.52182954 e 0.3283427 Incl. 1.74022 +0.30339377 +0.24740417 P 1.56 H 21.9 G 0.15 U 9 Residuals in seconds of arc 110124 F51 0.0 0.0 110126 291 0.2- 0.5- 110127 291 0.5+ 0.2+ 110124 F51 0.3+ 0.1+ 110126 291 0.5- 0.3+ 110127 291 0.6- 0.1+ 110124 F51 0.2- 0.0 110126 291 0.7+ 0.1- 110125 F65 0.6- 0.3+ 110126 291 0.5+ 0.0 Ephemeris: 2011 BT15 a,e,i = 1.35, 0.33, 2 q = 0.9040 Date TT R. A. (2000) Decl. Delta r Elong. Phase V 2010 12 28 23 08 25.8 -08 00 03 0.3454 0.9186 69.1 90.4 22.6 ... 2011 01 12 00 29 16.8 +01 58 50 0.2938 0.9571 76.2 86.4 22.2 ... 2011 01 20 01 20 08.4 +08 13 51 0.2797 0.9857 82.2 81.5 22.0 ... 2011 01 26 02 01 27.1 +12 54 16 0.2773 1.0099 87.2 76.8 21.8 2011 01 27 02 08 32.1 +13 39 11 0.2777 1.0141 88.1 76.0 21.8 2011 01 28 02 15 39.5 +14 23 18 0.2783 1.0184 89.0 75.2 21.8 ... 2011 02 03 02 58 53.2 +18 26 02 0.2864 1.0452 94.0 70.2 21.7 ... 2011 02 11 03 55 43.7 +22 32 53 0.3093 1.0831 99.8 63.9 21.8 ... 2011 02 26 05 29 48.9 +26 08 42 0.3844 1.1583 106.3 55.1 22.1 Sonia Keys (C) Copyright 2011 MPC M.P.E.C. 2011-B43
2011 BT15 D = 0.14 km P = 2.1 h (assume rapid rotation; this places a conservative lower bound on the SNRs) OC albedo = 0.1 (a relatively conservative lower bound) UTC SNR/ SNR/ w DOY start date window RA, dec dist runs day run 52 357 2013 Dec 23 16:30-19:20 244, -31 0.036 141 34 3 52 358 2013 Dec 24 15:45-19:15 239, -30 0.035 174 44 3 52 359 2013 Dec 25 15:05-19:05 233, -28 0.034 209 56 4 52 360 2013 Dec 26 14:20-18:55 227, -26 0.033 245 69 5 52 361 2013 Dec 27 13:35-18:45 221, -23 0.032 279 80 5 52 362 2013 Dec 28 12:50-18:30 215, -21 0.032 310 89 5 Scheduled 52 363 2013 Dec 29 12:10-18:20 209, -18 0.032 336 93 6 01 364 2013 Dec 30 11:30-18:10 204, -15 0.033 355 93 5 01 365 2013 Dec 31 10:55-18:00 199, -12 0.034 368 89 5 01 001 2014 Jan 01 10:20-17:50 195, -9 0.035 375 82 5 01 002 2014 Jan 02 09:50-17:40 191, -6 0.036 377 73 4 01 003 2014 Jan 03 09:20-17:30 187, -4 0.038 375 63 4 01 004 2014 Jan 04 08:55-17:20 183, -1 0.040 369 53 3 01 005 2014 Jan 05 08:30-17:10 180, +1 0.042 361 45 3 Goldstone SNRs assume Ptx = 450 kW Arecibo SNRs UTC SNR/ SNR/ start date window RA, dec dist runs date run 2014 Jan 05 08:56-10:07 181, +1 0.042 52 760 110 2014 Jan 06 08:28-10:04 178, +3 0.044 67 820 110 2014 Jan 07 08:05-09:58 175, +4 0.046 76 780 99 2014 Jan 08 07:46-09:50 173, +6 0.049 78 680 83 2014 Jan 09 07:28-09:42 171, +7 0.051 81 580 69 Scheduled 2014 Jan 10 07:13-09:34 169, +9 0.054 80 490 58 Scheduled 2014 Jan 11 06:59-09:25 167, +10 0.056 78 410 49 2014 Jan 12 06:46-09:16 165, +11 0.059 76 340 41 2014 Jan 13 06:34-09:08 164, +12 0.062 74 290 35 2014 Jan 14 06:23-08:59 162, +13 0.065 73 240 30 2014 Jan 15 06:13-08:51 161, +14 0.068 71 200 25 2014 Jan 16 06:03-08:43 159, +14 0.071 68 170 22 2014 Jan 17 05:53-08:35 158, +15 0.074 65 140 19 2014 Jan 18 05:44-08:27 157, +16 0.078 63 120 16 2014 Jan 19 05:36-08:19 156, +16 0.081 61 100 14 2014 Jan 20 05:27-08:11 155, +17 0.084 59 89 12 2014 Jan 21 05:19-08:04 154, +17 0.087 57 77 11 2014 Jan 22 05:11-07:56 153, +18 0.091 52 64 9 2014 Jan 23 05:04-07:49 152, +18 0.094 50 55 8 2014 Jan 24 04:56-07:42 151, +18 0.098 48 47 7 2014 Jan 25 04:49-07:35 151, +19 0.102 46 41 6 Arecibo SNRs assume Ptx = 900 kw. Current transmitter power is closer to 600 kW. This object will be an excellent imaging target at Arecibo, where it should be possible to obtain images with resolutions as fine as 7.5 meters/pixel.
DAY START BOT EOT END FACILITY USER ACTIVITY 362 1120 1250 1625 1655 DSS-14 GSSR AST 2011 BT1T5 Goldstone tracks: UT UT PST Duration Round-trip SNR/ DOY Date TX Window TX Window hh:mm time (sec) Run --- ---- --------- --------- --------- --------- ---- 262 Dec 28 1255-1625 0455-0825 Dec 28 3:30 32 5 Transmit authorization starts at the end of precal. Arecibo tracks: 9 Jan 09 0728-0942 2328-0142 Jan 8- 9 2:14 51 69 10 Jan 10 0713-0934 2313-0134 Jan 9-10 2:21 54 58
From Horizons, 2013 Dec 16, Solution 30, # obs: 101 (2007-2013) Date__(UT)__HR:MN R.A._(J2000.0)_DEC. delta POS_3sigma DOP_S_3sig DOP_X_3sig RT_delay_3sig 2013-Dec-10 00:00 *m 285.66620 -32.75903 0.07612293791871 10.000 3.39 12.34 0.001867 2013-Dec-11 00:00 *m 284.36093 -32.98268 0.07255877633210 10.659 3.70 13.45 0.001755 2013-Dec-12 00:00 *m 282.88501 -33.20627 0.06906061837145 11.371 4.04 14.68 0.001633 2013-Dec-13 00:00 *m 281.21732 -33.42505 0.06563530774089 12.141 4.42 16.05 0.001502 2013-Dec-14 00:00 *m 279.33402 -33.63244 0.06229058026066 12.971 4.83 17.57 0.001363 2013-Dec-15 00:00 *m 277.20835 -33.81951 0.05903525575322 13.862 5.30 19.25 0.001215 2013-Dec-16 00:00 *m 274.81071 -33.97424 0.05587947215990 14.810 5.81 21.10 0.001063 2013-Dec-17 00:00 * 272.10906 -34.08061 0.05283496349368 15.811 6.37 23.13 0.000914 2013-Dec-18 00:00 * 269.06984 -34.11761 0.04991537845702 16.850 6.97 25.34 0.000784 2013-Dec-19 00:00 * 265.65980 -34.05813 0.04713662667456 17.907 7.62 27.70 0.000705 2013-Dec-20 00:00 * 261.84898 -33.86803 0.04451722185527 18.946 8.30 30.15 0.000720 2013-Dec-21 00:00 * 257.61518 -33.50569 0.04207856300410 19.919 8.97 32.62 0.000849 2013-Dec-22 00:00 * 252.95001 -32.92272 0.03984505450387 20.755 9.61 34.93 0.001072 2013-Dec-23 00:00 * 247.86596 -32.06668 0.03784391691051 21.363 10.15 36.89 0.001359 2013-Dec-24 00:00 * 242.40325 -30.88648 0.03610449731083 21.638 10.52 38.22 0.001687 2013-Dec-25 00:00 * 236.63389 -29.34102 0.03465688425890 21.468 10.62 38.61 0.002039 2013-Dec-26 00:00 * 230.66044 -27.40990 0.03352971870298 20.759 10.39 37.76 0.002399 2013-Dec-27 00:00 * 224.60767 -25.10347 0.03274731335521 19.463 9.77 35.52 0.002751 2013-Dec-28 00:00 * 218.60810 -22.46821 0.03232652883315 17.605 8.78 31.90 0.003078 2013-Dec-29 00:00 * 212.78526 -19.58381 0.03227416428322 15.297 7.47 27.17 0.003365 2013-Dec-30 00:00 * 207.23967 -16.55172 0.03258567295259 12.724 5.99 21.79 0.003603 2013-Dec-31 00:00 * 202.04121 -13.47868 0.03324566584401 10.123 4.48 16.30 0.003785 2014-Jan-01 00:00 *m 197.22849 -10.46089 0.03423004844148 7.752 3.09 11.24 0.003912 2014-Jan-02 00:00 *m 192.81326 -7.57357 0.03550910169866 5.892 1.95 7.09 0.003988 2014-Jan-03 00:00 *m 188.78729 -4.86717 0.03705065874660 4.831 1.26 4.57 0.004019 2014-Jan-04 00:00 *m 185.12926 -2.36916 0.03882274242737 4.670 1.22 4.43 0.004014 2014-Jan-05 00:00 *m 181.81054 -0.08866 0.04079539317626 5.119 1.56 5.67 0.003979 2014-Jan-06 00:00 *m 178.79943 1.97809 0.04294171351407 5.785 1.93 7.00 0.003922 2014-Jan-07 00:00 *m 176.06394 3.84288 0.04523830234934 6.442 2.22 8.08 0.003849 2014-Jan-08 00:00 *m 173.57350 5.52178 0.04766527925205 7.005 2.44 8.87 0.003764 2014-Jan-09 00:00 *m 171.29988 7.03253 0.05020606704022 7.452 2.59 9.42 0.003671 2014-Jan-10 00:00 *m 169.21761 8.39287 0.05284705412361 7.788 2.69 9.78 0.003572 Apparent Magnitudes, Solar Elongations, Lunar Elongations, and Lunar Illumination: Date__(UT)__HR:MN R.A._(J2000.0)_DEC. delta APmag S-O-T /r T-O-M/Illu% 2013-Dec-15 00:00 277.23916 -33.78741 0.05904043285921 27. 16.7642 /T 138.6/ 94.7 2013-Dec-16 00:00 274.84491 -33.94123 0.05588323922945 28. 14.5789 /T 151.4/ 98.2 2013-Dec-17 00:00 272.14697 -34.04681 0.05283716426623 29. 12.5924 /T 162.0/ 99.8 2013-Dec-18 00:00 269.11175 -34.08318 0.04991584042280 30. 11.1203 /T 164.7/ 99.5 2013-Dec-19 00:00 265.70595 -34.02330 0.04713516170373 31. 10.6600 /L 156.2/ 97.5 2013-Dec-20 00:00 261.89948 -33.83308 0.04451362861180 30. 11.6545 /L 143.4/ 93.9 2013-Dec-21 00:00 257.66996 -33.47095 0.04207263211521 28. 14.1187 /L 129.0/ 88.6 2013-Dec-22 00:00 253.00872 -32.88859 0.03983657765609 26. 17.7528 /L 113.9/ 82.0 2013-Dec-23 00:00 247.92794 -32.03350 0.03783270101181 24. 22.2727 /L 98.0/ 74.2 2013-Dec-24 00:00 242.46743 -30.85453 0.03609038429135 23. 27.4968 /L 81.5/ 65.4 2013-Dec-25 00:00 236.69885 -29.31044 0.03463977564273 22. 33.3051 /L 64.3/ 55.9 2013-Dec-26 00:00 230.72451 -27.38056 0.03350960167653 21. 39.5946 /L 46.4/ 45.8 2013-Dec-27 00:00 224.66913 -25.07503 0.03272428228448 20. 46.2547 /L 28.1/ 35.6 2013-Dec-28 00:00 218.66540 -22.44011 0.03230079466389 19. 53.1570 /L 10.5/ 25.7 2013-Dec-29 00:00 212.83718 -19.55545 0.03224604595622 18.88 60.1594 /L 14.0/ 16.6 2013-Dec-30 00:00 207.28546 -16.52258 0.03255557038018 18.44 67.1177 /L 33.2/ 8.9 2013-Dec-31 00:00 202.08058 -13.44841 0.03321402073889 18.09 73.9015 /L 53.5/ 3.4 2014-Jan-01 00:00 197.26151 -10.42940 0.03419730334018 17.84 80.4063 /L 74.0/ 0.5 2014-Jan-02 00:00 192.84027 -7.54096 0.03547566661380 17.65 86.5607 /L 94.3/ 0.6 2014-Jan-03 00:00 188.80880 -4.83370 0.03701689034004 17.51 92.3258 /L 114.2/ 3.8 2014-Jan-04 00:00 185.14585 -2.33515 0.03878893565384 17.42 97.6903 /L 133.5/ 9.7 2014-Jan-05 00:00 181.82281 -0.05445 0.04076178231838 17.36 102.6631 /L 151.9/ 17.8 2014-Jan-06 00:00 178.80793 2.01219 0.04290847875916 17.32 107.2660 /L 169.1/ 27.5 2014-Jan-07 00:00 176.06919 3.87662 0.04520557869413 17.31 111.5285 /L 171.3/ 37.9 2014-Jan-08 00:00 173.57595 5.55495 0.04763316562524 17.31 115.4828 /L 156.0/ 48.5 2014-Jan-09 00:00 171.29995 7.06497 0.05017463451335 17.32 119.1611 /L 140.6/ 58.9 2014-Jan-10 00:00 169.21564 8.42447 0.05281635276969 17.34 122.5942 /L 125.6/ 68.6
We don't know anything about the spin state of 2011 BT15, so we will start with a relatively coarse Doppler resolution in order to quickly see the echo. CW setup: --------------------------------------------------------------------------- TX polarization RCP RCV polarization LCP & RCP Frequency hops: no hops (+0.5 kHz offset) Bandwidth: 4000 Hz Sampling interval: 2500 x 0.1 usec PFS FFT: : 4000 for 1.0 Hz res Ranging setups: --------------------------------------------------------------------------- 10-usec baud 10 usec code 127 PRP 1270 usec FFT 128 ncoh 1 bandwidth 787 Hz resolution 6.15 Hz TXOFF +100Hz (echo in bin 64+16=80) --------------------------------------------------------------------------- 11-usec baud 11 usec code 127 PRP 1397 usec FFT 128 ncoh 1 bandwidth 716 Hz resolution 5.6 Hz TXOFF +100 Hz (echo in bin 64+18=82) ------------------------------------------------------------------------- 1-usec baud 1 usec code 127 FFT 512 ncoh 128 bandwidth 61.3 Hz resolution 0.12 Hz TXOFF +8 Hz -> echo would be centered at 256 + 67=323 ------------------------------------------------------------------------------- 0.25-usec ranging baud 0.25 usec code 255 FFT 128 ncoh 16 bandwidth 980 Hz resolution 7.7 Hz TXOFF +80 Hz -> echo would be centered at 64 + 10 = 74 ------------------------------------------------------------------------------- 0.125-usec ranging baud 0.125 usec code 255 FFT 128 ncoh 32 bandwidth 980 Hz resolution 7.7 Hz TXOFF +80 Hz -> echo would be centered at 64 + 10 = 74 _____________________________________________________________________ POSSIBLE RANGING SETUPS: (code=127, FFT=64, single-pol'n) These are from JX, w/ max-band (min-acc) options from Ray Jurgens. Currently configured for 5-sec records. _______________________________________________________________________ Setup Baud RP 1-acc 1-acc usec m usec band res acc band res _______________________________________________________________________ JX1XS110 11.000 1650 1397.0 715.8 11.2 2 358 5.6 JX1XS070 7.000 1050 889.0 1124.9 17.6 3 375 5.9 JX1XS020 2.000 300 254.0 3937.0 61.5 12 328 5.1 4 984 15.4 JX1XS010 1.000 150 127.0 7874.0 123.0 41 192 3.0 8 984 15.4 JX1XS005 0.500 75 63.5 15748.0 246.1 123 128 2.0 15 1050 16.4 JX1XS002 0.250 37.5 31.75 31496.1 492.1 492 64 1.0 30 1050 16.4 JX1XS001 0.125 18.75 15.875 62992.1 984.3 1970 32 0.5 60 1050 16.4 ____________________________________________________________________
OSOD and predicts are aardvark: Monostatic with the new waveform generator: /export/data3/osod/ops/2011bt15/PRDX.OUT.14v-14-14.s?? /PUNCH.OUT.14v-14-14.s?? /EPH.OUT.s?? POINTING TX Offsets Date (UTC) DOY hhmmss RA Dec Macro LHA Dec RTT OSOD ... to be added later ... Transmit offsets are given in millidegrees.
PRDX.OUT.14f-14-14.s?? ... to be added later ...
2011 BT15GOLDSTONE MASTERLOG
============================================================================== Receive TX Setup hops dwell code ncoh FFT runs start -stop OSOD offset Poln Notes ------------------------------------------------------------------------------
Dr. Lance A. M. Benner | PHONE: (818) 354-7412 Mail Stop 183-610 | FAX: (818) 393-4445 Jet Propulsion Laboratory | email: lance.benner@jpl.nasa.gov California Institute of Technology | Plan: To live long and prosper Pasadena, CA 91109-8099 http://echo.jpl.nasa.gov/asteroids/2011BT15/2011BT15_planning.html