Nova Sgr 2015 No. 2 fading as dust production rises
AAVSO Alert Notice 519June 15, 2015Nova Sgr 2015 No. 2 fading as dust production rises
Nova Sgr 2015 No. 2 (PNV J18365700-2855420; see AAVSOAlert Notice512 at http://www.aavso.org/aavso-alert-notice-512)is undergoing a significant fading visually as its infrared excess increases,indicating that substantial dust production is underway.
Nova Sgr 2015 No. 2 was discovered by John Seach(Chatsworth Island, NSW, Australia) at DSLR magnitude 6.0 on 2015 March 15.634UT. It brightened to V=4.3 by March 21, and has undergone five subsequentre-brightenings, the last to V=5.7 on June 1. Since then it has faded steadilyto V=8.2 on June 15, 1.6 magnitudes fainter than its faintest previous minimumsince outburst. For a light curve of observations in the AAVSO InternationalDatabase, see the webpage for this Alert Notice (http://www.aavso.org/aavso-alert-notice519) or use the AAVSO Light Curve Generator (http//www.aavso.org/lcg).
The Spitzer Space Telescope may observe this classicalnova if it can be diverted from its current mode and target. Severalprofessional astronomers are planning observations with other instrumentation.
Photometry and visual observations, spectroscopy, andpolarimetry are strongly encouraged. Near-infrared observations (J and H bands)would be particularly helpful.
Coordinates:R.A.18 36 56.84 Dec. -28 55 39.8(2000.0)
Charts for Nova Sgr 2015 No. 2 may be created using theAAVSO Variable Star Plotter (VSP) at http://www.aavso.org/vsp.A binocular sequence for this nova exists. Bright comparison stars may also befound using VSP and requesting an 'a' or 'b' scale chart. Charts showingfainter comparison stars may also be created.
Please submit observations to the AAVSO InternationalDatabase using the name "NOVA SGR 2015 NO. 2". Once a GCVS name hasbeen assigned, please use that name.
This AAVSO Alert Notice was compiled by Elizabeth O.Waagen.
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