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Paper text:
b supergiants are very important for stellar and galactic evolution , as they enrich their evironments with chemically processed material via their line - driven winds .
they show strong line profile variability .
their lines are wider than expected from their parameters .
the excessive width is due to macroturbulence .
both line profile variability and macroturbulence are indications of stellar pulsations .
however , so far only very few such supergiants were investigated to determine their pulsation periods .
hd 202850 is a late b - type supergiant star .
its stellar parameters ( @xcite ) are given in table  [ param ] .
it has been classified as b9 iab , and is located in the ob association cyg ob 4 at a distance of @xmath21 kpc .
it falls out of any previously calculated instability domains ( @xcite ) . in our previous work
, we described the 1.59 h pulsation period we detected ( see @xcite ) .
+    [ param ]
in 2012 we took a new set of 294 spectra distributed over 5 nights with the dao 1.2-m telescope .
exposures were five minutes long , with a signal - to - noise ratio between 150 and 250 .
the moment analysis showed variability in all three moments , and the first and the third moment seem to vary in phase .
due to high noise , the fft analysis did not show any pronounced peaks , therefore the period(s ) were estimated by fitting a combination of sine curves ( fig .
[ fig1 ] ) .
we found two new possible periods ( a @xmath3h period and a @xmath4h period ) .
s.t . acknowledges financial support from an iau grant .
m.k . and m.e.o .
acknowledge financial support from gar under grant number p209/11/1198 .
the astronomical institute ondejov is supported by the project rvo:67985815 .
hd 202850 is a late b - type supergiant . 
 it is known that photospheric lines of such stars vary . due to macroturbulence 
 the lines are much wider than expected . 
 macroturbulence has been linked to stellar pulsations . 
 it has been reported that there are several b supergiants that undergo pulsations . in our previous work 
 , we detected a pulsational period of @xmath0 hours in this object from data taken with the ondejov 2-m telescope . 
 we continued to investigate this object and we took several time series with the dao 1.2-m telescope . 
 our new data suggest that there may be some additional pulsational periods in this star . 
 we present our new results in this poster .