Showing posts with label possible nova. Show all posts
Showing posts with label possible nova. Show all posts

Tuesday, December 3, 2013

Possible Bright Nova in Centaurus

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Cen (TOCP Designation: PNV J13544700-5909080) we performed some follow-up of this object remotely through the 0.50-m f/6.8 astrograph + CCD + focal reducer of iTelescope network (MPC Code  Q62 - Siding Spring, AU).

On our images taken on December 03.68, 2013 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude  ~5.0 at coordinates:

R.A. = 13 54 45.22, Decl.= -59 09 04.5 (equinox 2000.0; UCAC-3 catalogue reference stars).

According to Vizier the nearest star (located at 1.538 arcsecond from the transient) to this position in the USNO-B1.0 catalogue is:

USNO-B1.0  0308-0442031   (J2000) 13 54 45.374 -59 09 03.52    mag. B2=15.52 R2 =15.12

Our confirmation image (click on it for a bigger version):


Below an animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1999). Click on the thumbnail below for a bigger version. 

 

UPDATE - December 04, 2013

According to CBET No. 3732, PNV J13544700-5909080 is now NOVA CENTAURI 2013. This nova has been discovered by John Seach (Chatsworth Island, NSW, Australia) in six CCD images obtained with a digital SLR camera (+ 50-mm-f.l. f/1.0 lens; limiting mag 11) taken on Dec. 2.692 UT. Low-resolution spectrograms reported independently by M. Locke and R. Kaufman show strong H_alpha and H_beta emission indicative of a nova.

by Ernesto Guido, Nick Howes & Martino Nicolini

Saturday, February 2, 2013

Possible Nova in Cepheus

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Cep (TOCP Designation: PNV J23080471+6046521) we performed some follow-up of this object remotely through the 0.43-m f/6.8 reflector + CCD of ITelescope network (MPC Code  I89 - Nerpio, Spain). 

On our images taken on February 02.8, 2013 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude 9.8 at coordinates:

R.A. = 23 08 04.70, Decl.= +60 46 52.0

(equinox 2000.0; USNO-B1.0 catalogue reference stars).

Our annotated confirmation image (click on it for a bigger version):


An animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1991). Click on the thumbnail for a bigger version:


Kazuyoshi Imamura (Okayama Univ. of Sci. team, JAPAN) reports on vsnet-alert mailing list that they "succeeded in obtaining a low-resolution spectrum (R~400) of the PNV J23080471+6046521 (in Cep) on February 2.526 UT at the OUS (Okayama Univ. of Sci.) observatory......From our result, this object is thought to be a classical nova (Fe II class)"

Credit: K. Imamura (Okayama Univ. of Sci. team, JAPAN)

UPDATE - February 03, 2013

According to Cbet No. 3397, PNV J23080471+6046521 is now NOVA CEPHEI 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 Feb. 2.4119 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera). Spectra confirming the nature of the nova have been obtained by K. Imamura (see above) and M. Fujii (Bisei Astronomical Observatory).

Ernesto Guido & Nick Howes

Tuesday, March 27, 2012

Possible Nova in Ophiuchus

Following the posting on the Central Bureau's Transient Object Confirmation Page about a possible Nova in Oph (TOCP Designation: PNV J17260708-2551454) we performed some follow-up of this object remotely through the 0.10-m f/5 reflector + CCD from MPC code H06 (Mayhill station, NM) of iTelescope network.

On our images taken on 2012, March 27.5 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude 10.9 at coordinates:

R.A. = 17 26 07.02, Decl.= -25 51 42.1

(equinox 2000.0; USNO-B1.0 catalogue reference stars).


Our confirmation image:



While below you can see an animation showing a comparison between our confirmation image and the archive POSS2/UKSTU plate (R Filter - 1997). Click on the thumbnail for a bigger version:



UPDATE - MARCH 29, 2012

According to Cbet 3072 issued on March 28, observers at Koyama Astronomical Observatory (KAO) and at Okayama University of Science (OUS) have obtained a spectra of this variable star. An H-alpha emission line can be seen in the spectrum. H_beta, Fe II, and O I 777.4-nm are also visible. These features suggest that the object is an "Fe II-type" classical nova. This nova, designated NOVA OPHIUCHI 2012, has been discovered by Hideo Nishimura (Miyawaki, Kakegawa, Shizuoka-ken) on three 13-s frames (limiting mag 13.5) taken on Mar. 25.789 UT with a Canon 200-mm f/3.2 lens and a Canon EOS 5D Digital Camera mounted on a Takahashi EM100 equatorial telescope at Gomyo, Kakegawa, Japan.

by Ernesto Guido, Giovanni Sostero & Nick Howes

Sunday, April 25, 2010

Possible Nova in Sagittarius

CBET circular No. 2261, issued on April 24, 2010, announces the discovery by K. Nishiyama & F. Kabashima (Japan) of a possible Milky Way nova (mag 11.2) in Sagittarius on two 40-s unfiltered CCD frames (limiting magnitude 13.2) taken around Apr. 23.782 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera).

We performed some follow-up of this object remotely through a 0.25-m, f/3,4 reflector + CCD, from GRAS Observatory (near Mayhill, NM).

On our images taken on April 25.4, 2010 we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 12.1 (UCAC2 Catalogue reference stars) at coordinates:

R.A. = 17 53 02.99, Decl.= -28 12 19.3

(equinox 2000.0; UCAC2 catalogue reference stars)

Our confirmation image:




This is an animation showing a comparison between our image and the archive DSS plate (IR Filter - 1980). Click on it for a bigger version.



Spectroscopic observations are required to confirm the real nature of this transient.

UPDATE - May 06, 2010

According to IUAC 9140, a spectra has been obtained at the Steward Observatory Bok 2.29-m telescope on Apr. 25.4 UT by L. A. Helton, T. Vonderharr, and C. E. Woodward and G. J. Schwarz. These observations confirm that this is a post-maximum classical nova. The spectra exhibit strong, broad H_alpha emission.

The permanent GCVS designation V5586 Sgr has been assigned to this nova.

V5586 SAGITTARII = NOVA SAGITTARII 2010 No. 2

by Ernesto Guido and Giovanni Sostero

Monday, February 22, 2010

Possible Nova in Scorpius

Following the posting on the Central Bureau's unconfirmed-objects webpage about a possible nova in Sco, on February 22.8, 2010 we performed some follow-up of this object remotely through through a 0.40-m, f/3.8 reflector + CCD, from GRAS Observatory (Moorook, Australia).

On our images we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 10.1 (UCAC2 Catalogue reference stars) at coordinates:

R.A. = 17 06 07.50, Decl.= -37 14 27.7
(equinox 2000.0; UCAC2 catalogue reference stars)

Our confirmation image:



This is an animation showing a comparison between our image and thearchive DSS plate:



Spectroscopic observations are required to confirm the real nature of this transient.

UPDATE - February 24, 2010

According to Cbet No 2183 this transient in Scorpius has been discovered by Koichi Nishiyama and Fujio Kabashima (Japan) on two 40-s unfiltered CCD frames (limiting magnitude 12.7) taken around Feb. 20.857 UT using a 105-mm f/4 camera lens (+ SBIG STL6303E camera).

On Cbet 2186 (issued on February 23), K. Ayani (BAO) reported that a low-resolution spectrum (range 400-800 nm; resolution 0.5 nm at H-alpha) of the probable nova was obtained with the BAO 1-m telescope on Feb. 23.88 UT. This shows prominent H-alpha emission with P-Cyg absorption upon a red continuum. These features show that the new object is a "Fe II"-type nova.

The transient is officially NOVA SCORPII 2010.


by Ernesto Guido and Giovanni Sostero

Saturday, February 20, 2010

Nova Ophiuchi 2010 (No. 2)

CBET circular No. 2176, issued on February 19, 2010, announces the discovery by Hideo Nishimura (Japan) of a possible nova (mag 9.4) in Ophiuchus on two 13-s frames taken on Feb. 18.845 UT using a Minolta 120-mm f/3.5 lens and a Canon EOS 5D Digital camera.

On our images taken on February 20.5, 2010 through a 0.25-m, f/3,4 reflector +CCD, from GRAS Observatory (near Mayhill, NM), we can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 9.4 (UCAC2 Catalogue reference stars) at coordinates:

R.A. = 17 26 32.15, Decl.= -28 49 41.8
(equinox 2000.0; UCAC2 catalogue reference stars).

According to Nishimura nothing is visible at this position on his survey frames taken during each month in the span 2009 Feb.-Oct. 15 and on 2010 Feb. 2, 4, 5, 7, and 13.84 UT (limiting mag 11).

Our confirmation image:


This is an animation showing a comparison between our image and the archive DSS plate:



On Vsnet mailing list Imamura-san (Okayama U. of Sci.) and Fujii-san have reported spectra of this object confirming it as a nova:


According to Taichi Kato "Halpha emission was accompanied by a P Cyg absorption (blue-shifted by1000 km/s). Balmer emission lines with P Cyg profiles (700 km/s for Halpha) and Fe II lines were visible."


by Ernesto Guido & Giovanni Sostero

Monday, January 18, 2010

Possible Nova in Ophiuchus

CBET circular No. 2128, issued on January 16, 2010, announces the discovery by Hideo Nishimura (Japan) of a possible nova (mag 8.4) on two 13-s frames taken on Jan. 15.857 UT with a Canon EOS 5D Digital Camera (+ Minolta 120-mm f/3.5 lens). The object is located at:

R.A. = 17h39m41s, Decl. = -21d39'47" (equinox 2000.0)

According to K. Kadota nothing is visible at this position on a red Digitized Sky Survey image from 1997 (limiting mag estimated to be 20 by S.Nakano).

Below the confirmation image of this outbursting object taken by K. Itagaki:



(Credit: K. Itagaki, Japan)

UPDATE - January, 23

According to CBET circular No. 2139, Hiroyuki Maehara (Kyoto University) reports that a low-resolution spectrum (range 400-800 nm) of this object was obtained on Jan. 22.890 UT with the 25-cm telescope at the Kwasan Observatory. The spectrum shows H_alpha and Fe II emission lines and suggests that this object is a classical nova just after maximum.

This transient has been designated: V2673 OPHIUCHI = NOVA OPHIUCHI 2010

by Ernesto Guido

Monday, November 9, 2009

NOVA SCUTI 2009

Following the posting on the Central Bureau's unconfirmed-objects webpage about a possible nova in Scuti, on 2009 November 09.08 we performed some follow-up of this object through a 0.25-m, f/3,4 reflector + CCD, from GRAS Observatory (near Mayhill, NM).

We can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 8.5 (UCAC-2 Catalogue reference stars) at coordinates:

R.A. = 18 43 45.57, Decl.= -07 36 42.0

(equinox 2000.0; UCAC-2 catalogue reference stars).

Our confirmation image:


The extreme stellar crowding due to nearby field stars makes this measurement rather difficult. A comparison with a DSS red plate(limiting magnitude about 20), obtained on 1996, Aug. 13, fail to show a clear unambiguous pre-outburst precursor.

This is an animation showing of our image and the DSS plate:

More details about the discoverer have been provided on the CBET circular No. 2008, issued of 2009 November 09. This CBET announces the discovery of Hideo Nishimura (Japan) of a possible nova (mag 8) on two 10-s CCD frames (limiting magnitude 11.5) taken on Nov. 8.3699 and 8.3700 UT using a Canon EOS 5D camera (+ Minolta 120-mm f/3.5 lens).


by Ernesto Guido & Giovanni Sostero

Wednesday, May 13, 2009

Possible Nova in Centaurus 2009

Following an alert note posted today by Grzegorz Pojmanski in the vsnet-alert newsgroup about a possible nova in Cen, on 2009 May. 13.57 we performed some follow-up of this object remotely through a 0.25-m, f/6 Ritchey-Chretien + CCD, from the RAS Observatory (Moorook, Australia).

We can confirm the presence of an optical counterpart with unfiltered CCD magnitude about 8.6 (UCAC-2 Catalogue refernce stars) at coordinates:

R.A. = 13h31m15.77s, Decl. = -63o57'38".6 (equinox 2000.0; UCAC-2 catalogue reference stars).

Comparison with an Anglo-Australian Observatory Schmidt red plate (limiting magnitude about 20), obtained on 1997, Feb. 05, show that this position is nearly coincident with a field star, whose position end figures are 15s.68, 38".6, and magnitude about 15 (however, the extreme stellar crowding due to nearby field stars, makes this measurement rather difficult).

Our image of this transient is available at the following URL:

http://tinyurl.com/qlbesc

UPDATE

This nova has been designated V1213 Cen. For more info see also this paper on NATURE.


by Ernesto Guido and Giovanni Sostero