MM Sco - new SU UMa-type dwarf nova


MM Sco outburst

Relatively rare outburst (the last reported one in 2001 April). Probably worth further observing.

  YYYYMMDD(UT)   mag  observer
  20020829.523  <140  (Rod Stubbings)
  20020830.526  <140  (Rod Stubbings)
  20020831.455  <140  (Rod Stubbings)
  20020901.462  <142  (Rod Stubbings)
  20020903.403  <140  (Rod Stubbings)
  20020904.415  <140  (Rod Stubbings)
  20020905.428   140  (Rod Stubbings)
  20020905.440   140  (Rod Stubbings)
  20020906.410   134  (Rod Stubbings)
  20020906.431   134  (Rod Stubbings)
  20020907.401   135  (Rod Stubbings)
  20020908.426   135  (Rod Stubbings)


(vanet-alert 7468)

MM Sco: new SU UMa-type dwarf nova!

Dear Colleagues,

Berto Monard took time-series CCD photometry of MM Sco (currently in long, bright outburst) on Sep. 10-11, and just sent us the data. The data clearly shows the presence of 0.1 mag humps, which are most likely superhumps! A preliminary period analysis suggests that the superhump period is around 0.062 d. Further time-series CCD photometry is most urgently requested in order to firmly establish the classification and the period. (The presence of a close neighbor companion may have somewhat reduced the above reported amplitude).

For readers interests, past calls for observations of MM Sco can be found in vsnet-alert 946 and vsnet-campaign 305.

Congratulations, Berto!

Taichi Kato
VSNET Collaboration team

Past information

(vsnet-alert 946) The dwarf nova MM Sco is undergoing a relatively rare outburst as reported by R. Stubbings.

  YYMMDD(UT)   mag  observer
  970527.438   138  (R. Stubbings)
  970527.590   137  (R. Stubbings)
MM Sco has a relatively large outburst amplitude (13.0-18.5B in Downes et al. 1997; faint quiescent counterpart indicated, see also Vogt and Bateson 1982, A&AS, 48, 383). GCVS 3 gave a cycle length of >500 days, while GCVS 4 gives 28: days. Vanmunster and Howell's famous "Outburst Activity Database" lists only two outbursts. More observations are clearly needed.
Taichi Kato
(vsnet-campaign 305)

MM Sco bright outburst

From vsnet-outburst message. MM Sco is likely a long-period SS Cyg star (long outbursts only), but there may not have been an attempt to check short-term variability during outburst. Another reason to put this on this campaign list is that the star possibly needs outburst astrometry, since the crowded field has made unambiguous identification a bit difficult.

VSNET light curve (requires Java)

Light curve

VSNET data search


Return to HomePage

Return to Daisaku Nogami's page

Powered by ooruri technology