Z Canis Majoris -- a brightening jet-feature?

[pgc hunter]

Originally Posted by ngcles

Hi All,

More details later -- just got home from Bargo and it is about 6am. Can report a positive sighting of the jet from Z Canis Majoris confirmed by three other observers (1x very experienced, 1x moderately experienced, 1x beginner-moderately experienced).

x317 unfiltered was best. Suspected at x185. x247 difficult but not overly so averted vision essential. Best at x317 -- still A.V. Any filter kills it stone dead. Suspect minimum aperture will be in the 14-16" range. Very LSB and small but definite. Z Cma despite the spectral classification, seems weakly yellowish at x247. Seeing 6/10. SQM-L = 21.22

Happy boy! Suspect I may be the first southern hemisphere observer to detect it visually


Best,

Les D

Wonder how I missed this thread... very interesting new development here and a nice new visual challenge to try my luck on!

Nice work Les! I'll give it a crack next clear night, hoping for good seeing so can ramp up the mag. Brings to mind another CMA object - VY Canis Majoris, has anyone ever seen the nebulosity around this star?

[Merlin66 (Ken)]

A couple of close up images would be nice to see!

[astroron (Ron)]

Originally Posted by pgc hunter

Wonder how I missed this thread... very interesting new development here and a nice new visual challenge to try my luck on!

Nice work Les! I'll give it a crack next clear night, hoping for good seeing so can ramp up the mag. Brings to mind another CMA object - VY Canis Majoris, has anyone ever seen the nebulosity around this star?

Sab VY Canis Majoris is one of my favourite objects in CM it is a mini Homunculus with the bottom lobe missing, But has also been compared to the NIKE Swish
Cheers

[pgc hunter]

Originally Posted by astroron

Sab VY Canis Majoris is one of my favourite objects in CM it is a mini Homunculus with the bottom lobe missing, But has also been compared to the NIKE Swish
Cheers

sweeet as! I had this object at the back of my mind for a while now but never got 'round to it. Thanks Ron your obs is encouraging, will make sure to check it out next time. Sounds like I'm in with a decent shot

[Rob_K]

A VSNET Alert has been put out about Z CMa:

Z CMa: rising again!

The object has now reached a level brighter than the 2009 maximum
and appears to be still rising.
Kyoto Wide-field Survey = survey program led by Maehara-san at Kwasan
Observatory.

Recent obs are included in the alert:

http://ooruri.kusastro.kyoto-u.ac.jp...et-alert/12767


Cheers -

[Rob_K]

AAVSO have now put up a Special Notice about the current 'outburst' of Z CMa, calling for observations:

Bright outburst of the pre-main sequence variable Z CMa

February 4, 2011: John Bortle, Stormville, NY, reports that the pre-main sequence binary variable Z CMa is in outburst, according to his observation of 2011 February 4.0 UT at visual magnitude 8.5. Observations in the AAVSO International Database confirm this outburst, which may have begun as long ago as April 2010, when it began brightening slightly from visual magnitude 10.7. When Z CMa emerged from its seasonal gap in November 2010, it was already 9th magnitude.

The current outburst is as bright as the one that occurred in 2008, the brightest in the star's known history. Z CMa is a very interesting object, a binary composed of a Herbig Be star and an FU Ori star. The Herbig star is embedded in nebulosity. The system is an x-ray source and has an x-ray jet. According to Stelzer et al. (2009, Astronomy & Astrophysics v.499, p.529, and astro-ph arXiv:0903.4060), the FU Ori star is the source of both the optical outbursts and the x-ray emission.

Observations of Z CMa are strongly encouraged, both during the current outburst and throughout the observing season. With its range of visual magnitude ~8.0-10.5, it is an excellent visual observing target. Visual, PEP, and CCD observations are welcome.

Coordinates: RA 07:03:43.16 Dec -11:33:06.2 (J2000.0)

Charts for Z CMa may be created using VSP:
http://www.aavso.org/vsp

Please report observations to the AAVSO International Database using the name Z CMA.

Our thanks to John Bortle for drawing our attention to the current outburst of this interesting system!

http://www.aavso.org/aavso-special-notice-232


Cheers -