Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Sun, 05/14/2017 - 09:52
AT 2017eaw in NGC 6946 (SN:)
Patrick Wiggins, Tooele, UT, USA, reports his discovery of a possible supernova (mag about 12.8) on an unfiltered CCD frame taken 2017 May 14.2383 UT using a 0.35-m f/5.5 reflector near Erda, UT, USA. The new
object is located at
R.A. 20h34m44.24s, Decl. +60°11’35.9” (equinox 2000.0),
about 153” NW of the center of NGC 6946. The discovery image was posted temporarily at URL
http://users.wirelessbeehive.com/~paw/ngc6946-1.jpg
Wiggins notes that nothing was visible at this position on an image taken on May 12.
http://www.cbat.eps.harvard.edu/unconf/followups/J20344424+6011359.html
AT 2017eaw: https://wis-tns.weizmann.ac.il/object/2017eaw
Clear skies,
Patrick Schmeer
Definetly a new object! Shot a short BVI sequence (BVI 3X45sec, 3x30sec,& 3x30sec 2x2 bin) just as it got light. Shot with a C-11 at F/6 with Astrodon photometric BVI filters. Here are the un-transformed magnitudes from the fully calibrated exposures:
AT 2017eaw,2457888.0028414354,13.450,0.020,B,NO,STD,115,12.385,126,13.766,1.129,NA,X18779ASY,na
AT 2017eaw,2457888.0035821763,13.423,0.019,B,NO,STD,115,12.380,126,13.760,1.128,NA,X18779ASY,na
AT 2017eaw,2457888.0043229167,13.445,0.022,B,NO,STD,115,12.402,126,13.767,1.127,NA,X18779ASY,na
AT 2017eaw,2457888.0053125001,13.143,0.021,V,NO,STD,115,12.322,126,13.388,1.127,NA,X18779ASY,na
AT 2017eaw,2457888.0058796294,13.102,0.022,V,NO,STD,115,12.325,126,13.366,1.126,NA,X18779ASY,na
AT 2017eaw,2457888.0064467592,13.150,0.025,V,NO,STD,115,12.331,126,13.340,1.126,NA,X18779ASY,na
AT 2017eaw,2457888.0072453702,12.753,0.043,I,NO,STD,115,12.769,126,13.422,1.125,NA,X18779ASY,na
AT 2017eaw,2457888.0078125000,12.680,0.044,I,NO,STD,115,12.757,126,13.418,1.125,NA,X18779ASY,na
AT 2017eaw,2457888.0083796298,12.680,0.048,I,NO,STD,115,12.755,126,13.403,1.125,NA,X18779ASY,na
I'll upload this data transformed once we get a designation that in uploadable to the AASVO database. The average for my transformed magnitudes are:
B:13.298, V:13.155, and I:12.715
I might try to take a spectum tomorrow night on this object with my LISA spectroscope on the CDK17.
James
There was a poor sequence for the NGC 6946 FOV which I have now updated with APASS & Hendon data. As of the moment (05/14/17 ~ 1942 UT) this object has not made it into the VSX data base yet so you will have to use the coordiantes of this target to secure a chart from the VSP.
20 34 44.24 +60 11 35.9
Good Observing & Ad Astra,
Tim Crawford, CTX, Sequence Team
Here is a chart for V0778 Cyg which is a few minutes to the SE of the transient. I plan to try using the chart to find it in about three hours. The star symbol marks the approx. location.
People might find it convenient that the VSP allows to have a DSS image of the field overlayed,
Here's an example for a V778 Cyg chart.
You can also use the VSP chart for SN 2008S. The new SN candidate is fairly close to the center of the field in this chart. It is 6 arcmin directly north of the position of SN 2008S.
If you request the photometry sequence for this chart I think you'll get Tim's new sequence. I see 10 APASS stars in the sequence for a 40 arcmin chart (centered on SN 2008S)
Phil
AAVSO Alert Notice 577 announces the discovery of SN 2017eaw in NGC 6946. Please see the Alert Notice for details and observing instructions.
Many thanks, and good observing,
Elizabeth Waagen, AAVSO HQ
In AAVSO Alert Notice 577 on SN 2017eaw, I inadvertantly credited David Boyd's CCD observations of the supernova to David Blane. I have corrected the text of the Alert Notice on the webpage, and I have notified Dan Green at CBAT, as two of David's observations were included in CBET 4390. I apologize sincerely to David for my error!
Good observing,
Elizabeth Waagen, AAVSO HQ