DW Uma

 

IMAGE DETAILS

Object ............................................ DW Uma
Constellation ..............................  Ursa Major
V. Magnitude + Variability......... 13.6-18.0 V / 
NL/VY+E
RA / DEC ..................................... 10h:33m.53sec / +5846m.55sec
Period ........................................... 
0.1366065324 days
Comparison star .........................  GSC 3822:1157
Check star .................................... G
SC  3822:983

Date + Time ................................  11/04/2020  - 19:00 UTC
Location .................................... 
"Nunki Observatory" - Skiathos
Optics .........................................  
Officina Stellare Advanced RILA 400 f/5.25
Tools ..........................................   THE SKY X
Camera ......................................  
 SBIG STXL11002  with FW8G-STXL (Astrodon filters)
Exposure Time.........................    Rc: 5.3  Hours
Mount .......................................   Paramount ME
Guiding ....................................    Unguided
Processing Details ..................   ACP , Muniwin
More Details ...........................    Environment Temperature : 13 oC Camera Temperature -25 οC
Sky temperature .....................   12.0. οC
Notes ........................................   Weather: Clear  Transparence:
Medium  Humidity : 75-85%
Moon Illumination ...............    72%

Target details .........................  
NL / VY+E

NL
Nova-like stars. Cataclysmic variables where the mass transfer rate is above a certain limit and their accretion disks are stable because they are nearly fully ionized to their outer (tidal cut off) boundary and this condition suppresses dwarf nova outbursts. Also known as UX (UX Ursae Majoris stars).
VY
VY Scl subtype. They are cataclysmic binary systems with a hot (35,000-65,000 K) and luminous white dwarf that occasionally undergo fadings of more than 1 magnitude (up to several magnitudes) due to a low rate of mass transfer. These fadings might last from days to years. At maximum they vary up to 1 magnitude. They are usually nova-like variables that show no outbursts but some dwarf nnovae also show similar fadings. Orbital periods usually range between 0.12 and 0.18 d.
Examples: VY SclMV Lyr.
 

'The Artistic Image above, reproduced courtesy of Mark A. Garlick / markgarlick.com. No unauthorized use".

 

Nikos Paschalis