"Pseudo-MPEC" for ZTF00Y9 = ZTF00Yp = ZTF00ah

Created 2018 Sep 21 14:59:28 UT using Find_Orb

Click here for an explanation of pseudo-MPECs

TLEs are available for this object, and for some of the other objects on these pages. Be warned that, for reasons discussed below, the TLEs for this particular object may not be all that good.

On 2018 September 5, shortly after the Zwicky Transient Facility found the object ZTF00ah and posted astrometry for it on the NEOCP, I suspected a possible linkage to ZTF00Yp. (In both cases, a geocentric orbit had roughly similar elements, especially in inclination and ascending node.) I was able to find a linked orbit, though only by having an unusually high area/mass ratio. When I did this, though, I was able to link in ZTF00Y9, which I'd previously had no really good reason to think was even geocentric.

I was a little hesitant to call this a firm linkage, because the area/mass ratio indicated something with the mass of dozens of grams, but a meter or so across. It would have to be something such as a loose bit of insulation, for example. However, Marco Micheli was willing to try to recover this object from the ESA Optical Ground Station (OGS) at Tenerife, in the Canary Islands. We were not very confident that this would work. The ephemeris uncertainties were a little high, and the object was only about 23 degrees above the horizon. However, the object was recovered successfully. That gave us four nights, and we can say with confidence that it's a real object being pushed around strongly by solar radiation pressure, similar to ZTF00V9, ZTF00pm = ZTF01Ls, and ZTF00hf = ZTF00YB.

 
 Astrometry: 
     ZTF00Y9  C2018 09 02.37704 00 43 13.06 -06 42 27.0          16.97gUNEOCPI41
     ZTF00Y9  C2018 09 02.37738 00 43 17.00 -06 41 50.6          16.97gUNEOCPI41
     ZTF00Y9  C2018 09 02.42744 00 53 07.74 -05 15 35.3                UNEOCPI41
     ZTF00Y9  C2018 09 02.42779 00 53 11.88 -05 14 58.0                UNEOCPI41
     ZTF00Yp  C2018 09 03.36436 00 23 34.45 -08 39 40.8          16.36RUNEOCPI41
     ZTF00Yp  C2018 09 03.36471 00 23 38.30 -08 39 06.3          16.36RUNEOCPI41
     ZTF00Yp  C2018 09 03.39954 00 30 05.39 -07 40 22.7          16.79gUNEOCPI41
     ZTF00Yp  C2018 09 03.39988 00 30 09.25 -07 39 47.5          16.79gUNEOCPI41
     ZTF00ah  C2018 09 05.41781 23 59 26.70 -10 20 20.6          16.64gUNEOCPI41
     ZTF00ah  C2018 09 05.41816 23 59 30.80 -10 19 42.2          16.64gUNEOCPI41
     ZTF00ah  C2018 09 05.41872 23 59 37.58 -10 18 38.8          16.56gUNEOCPI41
     ZTF00ah  C2018 09 05.41906 23 59 41.64 -10 17 59.7          16.56gUNEOCPI41
     ZTF00Y9  C2018 09 09.00482202 34 12.537+03 08 50.38         16.6 GV     J04
     ZTF00Y9  C2018 09 09.00488902 34 14.556+03 09 00.99         17.0 GV     J04
     ZTF00Y9  C2018 09 09.00496102 34 16.712+03 09 12.46         16.5 GV     J04
     ZTF00Y9  C2018 09 09.00503102 34 18.807+03 09 23.33         16.6 GV     J04
     ZTF00Y9  C2018 09 09.00510102 34 21.006+03 09 34.92         17.1 GV     J04
     ZTF00Y9  C2018 09 09.00517002 34 23.097+03 09 46.48         16.6 GV     J04
     ZTF00Y9  C2018 09 09.00524102 34 25.228+03 09 57.65         16.5 GV     J04
     ZTF00Y9  C2018 09 09.00531202 34 27.367+03 10 08.93         16.6 GV     J04
     ZTF01Ux  CK180919:075937481013.78282379-04.82016290         16.22RU     I41
     ZTF01Ux  CK180919:080007443013.79672582-04.81063837         16.22RU     I41
     ZTF01Ux  CK180919:083841901014.88927428-04.06928157         16.68gU     I41
     ZTF01Ux  CK180919:083911926014.90306192-04.05968686         16.68gU     I41

Station data:
(I41) Palomar Mountain--ZTF  (N33.357340 W116.859780)  US/California.
   Observer A. U. Tomatic. Measurer Q.-Z. Ye.
(J04) ESA Optical Ground Station, Tenerife  (N28.300924 W16.511830)  Canary
   Islands (Spain).  Observer D. Abreu. Measurers M. Micheli, D. Koschny, A.
   Knöfel, E. Schwab, M. Busch. 1.0-m f/4.4 reflector + CCD.

Orbital elements:  ZTF00Y9 = ZTF00Yp = ZTF00ah
   Perigee 2018 Sep 2.839928 +/- 8.53e-5 TT = 20:09:29 (JD 2458364.339928)
Epoch 2018 Sep  3.0 TT; AMR 42.141 +/- 0.0727 m2/kg          Gray
M  54.352436 +/- 0.028              (J2000 equator)
n 339.548979358 +/- 0.00187         Peri.  165.550539 +/- 0.016
a 43920.62921 +/- 0.161             Node    19.042975 +/- 0.018
e   0.75046931 +/- 7.39e-5          Incl.   22.036672 +/- 0.00046
P1526.70m/1.060d           H 32.2   G  0.15   U  8.5
q 10959.54478 +/- 3.28    Q 76881.71364 +/- 3.03
From 24 observations 2018 Sept. 2-19; mean residual 23".796
Residuals in arcseconds: 
180902 I41 32.3+ 9.60+    180905 I41 31.5- 21.4-    180909 J04 36.3- 13.6-
180902 I41 31.9+ 11.6+    180905 I41 32.3- 22.0-    180909 J04 36.4- 13.1-
180902 I41 14.6- 14.7-    180905 I41 30.4- 20.9-    180909 J04 36.9- 13.3-
180902 I41 16.5- 14.8-    180905 I41 30.1- 19.6-    180909 J04 37.2- 13.5-
180903 I41 7.61+ 1.34-    180909 J04 36.1- 13.5-    180919 I41 20.6+ 13.9+
180903 I41 6.60+ 2.05-    180909 J04 36.3- 13.6-    180919 I41 19.8+ 14.0+
180903 I41 7.77- 10.1-    180909 J04 36.8- 13.6-    180919 I41 39.9+ 26.6+
180903 I41 6.70- 9.62-    180909 J04 37.3- 14.0-    180919 I41 38.7+ 26.5+

Ephemerides (geocentric):
Date (UTC) HH   RA              Dec         delta  elong  mag " sig PA
---- -- -- --  -------------   -----------  ------ -----  --- ---- ---
2018 09 19 00  23 09 50.345   -12 02 27.63   57595 166.6 15.9 38.2  70
2018 09 19 01  23 27 51.972   -10 24 34.05   62979 170.3 16.0 30.2  69
2018 09 19 02  23 43 07.348   -08 57 53.28   67418 172.7 16.0 24.4  68
2018 09 19 03  23 56 33.245   -07 39 00.88   71013 173.3 16.1 20.0  67
2018 09 19 04  00 08 44.856   -06 25 36.44   73833 172.4 16.2 16.4  67
2018 09 19 05  00 20 05.915   -05 15 57.36   75930 170.6 16.3 13.5  66
2018 09 19 06  00 30 53.718   -04 08 43.69   77336 168.3 16.5 11.1  65
2018 09 19 07  00 41 21.896   -03 02 48.69   78074 166.0 16.6 9.03  64
2018 09 19 08  00 51 42.134   -01 57 12.36   78153 163.5 16.7 7.27  62
2018 09 19 09  01 02 05.391   -00 50 56.45   77576 160.9 16.7 5.77  61
2018 09 19 10  01 12 42.956   +00 17 00.39   76333 158.2 16.8 4.54  58
2018 09 19 11  01 23 47.585   +01 27 47.83   74406 155.4 16.8 3.58  55
2018 09 19 12  01 35 35.009   +02 42 50.99   71764 152.3 16.8 2.96  51
2018 09 19 13  01 48 26.284   +04 04 01.08   68361 149.0 16.8 2.76  49
2018 09 19 14  02 02 51.911   +05 33 53.16   64131 145.2 16.8 3.19  51
2018 09 19 15  02 19 39.932   +07 16 18.25   58982 140.9 16.7 4.68  56
2018 09 19 16  02 40 13.799   +09 17 26.59   52779 135.5 16.6 8.22  61
2018 09 19 17  03 07 18.330   +11 48 03.21   45320 128.5 16.5 16.3  66
2018 09 19 18  03 47 26.977   +15 08 33.21   36286 118.4 16.3 36.7  70
2018 09 19 19  05 02 17.151   +19 54 47.16   25179 100.1 16.1  107  77
2018 09 19 20  09 02 05.404   +20 39 16.08   12181  44.7 18??  623 101
2018 09 19 21  18 07 05.943   -22 20 39.64   15372  95.0 15.2  488  96
2018 09 19 22  20 54 37.974   -20 57 48.38   28213 133.5 15.3  162  80
2018 09 19 23  21 58 33.076   -17 33 32.70   38744 148.6 15.6 90.1  75
2018 09 20 00  22 35 30.216   -14 54 41.28   47345 157.5 15.8 60.9  72
2018 09 20 01  23 01 15.492   -12 47 55.44   54468 163.6 15.9 45.0  71
2018 09 20 02  23 21 09.573   -11 01 52.09   60394 168.1 15.9 35.1  69
2018 09 20 03  23 37 34.928   -09 29 37.03   65306 171.3 16.0 28.1  68
2018 09 20 04  23 51 46.364   -08 06 51.80   69325 173.1 16.0 22.9  68
2018 09 20 05  00 04 28.031   -06 50 45.14   72538 173.1 16.1 18.9  67