Sunday, June 9, 2013

New Comet: C/2013 L2 (CATALINA)

Cbet nr. 3548, issued on 2013, June 09, announces the discovery of an apparently asteroidal object (discovery magnitude ~19.6)  by R. A. Kowalski on CCD images obtained with the Catalina Sky Survey 0.68-m Schmidt telescopeon June 02.  After posting on the Minor Planet Center's NEOCP webpage, this apparently asteroidal object as been found to show cometary features by by astrometric observers elsewhere. The new comet has been designated C/2013 L2 (CATALINA).

We performed follow-up measurements of this object, while it was still on the neocp. Stacking of 18 R-filtered exposures, 30-sec each, obtained remotely, from the Haleakala-Faulkes Telescope North on 2013, June 04.5, through a 2.0-m f/10.0 Ritchey-Chretien + CCD (operated by Las Cumbres Observatory Global Telescope Network), shows that this object is a comet: sharp central condensation, surrounded by a faint coma nearly 4" in diameter.

Below you can see our image. Click on it for a bigger version.

M.P.E.C. 2013-L41 assigns the following preliminary parabolic orbital elements to comet C/2013 L2: T 2012 Apr. 29.80; e= 1.0; Peri. = 359.60; q = 4.77;  Incl.= 106.44

by Ernesto Guido & Nick Howes

Monday, June 3, 2013

Possible Nova in Sco - PNV J17335943-3606216

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Sco (TOCP Designation: PNV J17335943-3606216) we performed some follow-up of this object remotely through the 0.50-m f/6.8 astrograph + CCD + f/4.5 focal reducer of iTelescope network (MPC Code  Q62 - Siding Spring, AU).

On our images taken on June 03.7, 2013 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude 11.5 at coordinates:

R.A. = 17 33 59.44, Decl.= -36 06 20.7

(equinox 2000.0; UCAC-3 catalogue reference stars).

Our annotated confirmation image (click on it for a bigger version). North is up, East is to the left:

An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1996). Click here or on the thumbnail for a bigger version:

Possible Nova in Sco - PNV J17335943-3606216 - by E. Guido & N. Howes - June 03, 2013 photo pnv_J17335943-3606216_zps5b706e40.gif

UPDATE - June 04, 2013

According to Cbet No. 3542, PNV J17335943-3606216 is now NOVA SCORPII 2013. This nova has been discovered by Koichi Nishiyama and Fujio Kabashima (Japan) on two 40-s unfiltered CCD frames (limiting magnitude 13.5) taken around June 3.6146 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera). Spectra obtained by C. Buil (the spectrum shows a very reddened object, with an intense H-alpha emission line - equivalent width 2.9 nm; FWHM = 1200 km/s ), and independently by T. Bohlsen indicate a probable nova.

Credit: C. Buil, Castanet, France

by Ernesto Guido & Nick Howes