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IAUC 3145: 1977 UB; III Zw 2

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                                                  Circular No. 3145
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Cables: SATELLITES NEWYORK  Telex: 921428  Telephone: (617) 864-5758

1977 UB
     Further computations by J. G. Williams, Jet Propulsion Laboratory,
and by B. G. Marsden, Center for Astrophysics, have suggested
that 1977 UB is just past aphelion in an orbit having q < 10 AU, e
> 0.3.  Using an ephemeris by Marsden, C. T. Kowal, Hale Observatories,
has identified the object on exposures he had obtained with
the 122-cm Schmidt telescope in 1969.  His measurements are:

     1969 UT             R.A. (1950) Decl.       mpg
     Sept.10.36875    0 13 49.91   + 4 49 19.5   18
          11.34167    0 13 40.79   + 4 48 18.9

Improved orbital elements by Marsden satisfy the 17 observations
within 2".  Perturbations by Jupiter to Pluto were considered:

     T = 1996 Feb. 13.170 ET          Epoch = 1977 Sept. 14.0 ET
 Peri. = 339.005                          e =   0.37860
 Node  = 208.716      1950.0              a =  13.6991 AU
 Incl. =   6.923                         (n =   0.019439)
     q =   8.51259 AU                     P =  50.70 years

     At perihelion the object should attain mpg ~ 14.5, but a cursory
examination of minor-planet observations around the perihelion
passages in 1945 and 1895 (when the position would have been near R.A.
= 12.0h, Decl. = -5o) has not revealed any identifications.  A past
ephemeris will be supplied on request.  An integration over 1400-
2550 revealed no substantial changes in the orbit of the object,
but approaches within 1.1 and 1.3 AU of Saturn were noted.  The
mean period, ~ 49 years, suggests that the motion is influenced
principally by the 3:5 resonance with Saturn but also by the 1:4
resonance with Jupiter and the 2:1 resonance with Uranus.

III Zw 2
     A. E. Wright, C.S.I.R.O. Division of Radiophysics; D. A. Allen,
P. A. Krug, D. C. Morton and M. G. Smith, Anglo-Australian Observatory,
report a new outburst of the type I Seyfert compact galaxy
III Zw 2 (Huchtmeier and Wright 1973, Astrophys. Lett. 15, 209; R.A. =
0h07m57s, Decl. = +10o42.0', equinox 1950.0).  Recent observations with
the Parkes radio telescope show that the 14.5-GHz flux density has
risen to 1050 mJy from a level of 370 mJy in 1977 June and 100 mJy
in 1975 Jan.  Optical, infrared and x-ray observations are urged.

1977 November 30               (3145)              Brian G. Marsden

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