subroutine astro(AppDir,nyear,month,nday,uth,nfreq,Mygrid, + NStation,mode,MoonDX,AzSun,ElSun,AzMoon,ElMoon0, + ntsky,doppler00,doppler,dbMoon,RAMoon,DecMoon,HA,Dgrd,sd, + poloffset,xnr,auxra,auxdec,azaux,elaux) C Computes astronomical quantities for display in JT65, CW, and EME Echo mode. C NB: may want to smooth the Tsky map to 10 degrees or so. character*80 AppDir,fname character*6 MyGrid,HisGrid logical first,ltsky real LST real lat,lon real ldeg integer*1 n1sky(129600) integer*2 nsky common/sky/ nsky(360,180) common/echo/xdop(2),techo,ElMoon,mjd equivalence (n1sky,nsky) data first/.true./ data rad/57.2957795/ save if(first) then do i=80,1,-1 if(ichar(AppDir(i:i)).ne.0 .and. + ichar(AppDir(i:i)).ne.32) goto 1 enddo 1 lenappdir=i call zero(nsky,180*180) fname=Appdir(1:lenappdir)//'/TSKY.DAT' #ifdef CVF open(13,file=fname,status='old',form='binary',err=10) read(13) nsky close(13) #else open(13,file=fname,status='old',access='stream',err=10) read(13) nsky close(13) #endif ltsky=.true. first=.false. endif go to 20 10 ltsky=.false. 20 call grid2deg(MyGrid,elon,lat) lon=-elon call sun(nyear,month,nday,uth,lon,lat,RASun,DecSun,LST, + AzSun,ElSun,mjd) freq=nfreq*1.e6 call MoonDop(nyear,month,nday,uth,lon,lat,RAMoon,DecMoon, + LST,HA,AzMoon,ElMoon,ldeg,bdeg,vr,dist) C Compute spatial polarization offset xx=sin(lat/rad)*cos(ElMoon/rad) - cos(lat/rad)* + cos(AzMoon/rad)*sin(ElMoon/rad) yy=cos(lat/rad)*sin(AzMoon/rad) if(NStation.eq.1) poloffset1=rad*atan2(yy,xx) if(NStation.eq.2) poloffset2=rad*atan2(yy,xx) techo=2.0 * dist/2.99792458e5 !Echo delay time doppler=-freq*vr/2.99792458e5 !One-way Doppler t408=ftsky(ldeg,bdeg) !Read sky map tsky=t408*(408.0/nfreq)**2.6 !Tsky for obs freq if(ltsky.and.(tsky.lt.3.0)) tsky=3.0 !Minimum = 3 Kelvin xdop(NStation)=doppler if(NStation.eq.2) then HisGrid=MyGrid go to 900 endif doppler00=2.0*xdop(1) if(mode.eq.2 .or. mode.eq.5) doppler=xdop(1)+xdop(2) if(mode.eq.3) doppler=2.0*xdop(1) dBMoon=-40.0*log10(dist/356903.) sd=16.23*370152.0/dist ! if(NStation.eq.1 .and. MoonDX.ne.0 .and. ! + (mode.eq.2 .or. mode.eq.5)) then if(NStation.eq.1 .and. MoonDX.ne.0) then poloffset=mod(poloffset2-poloffset1+720.0,180.0) if(poloffset.gt.90.0) poloffset=poloffset-180.0 x1=abs(cos(2*poloffset/rad)) if(x1.lt.0.056234) x1=0.056234 xnr=-20.0*log10(x1) if(HisGrid(1:1).lt.'A' .or. HisGrid(1:1).gt.'Z') xnr=0 endif tr=80.0 !Good preamp tskymin=13.0*(408.0/nfreq)**2.6 !Cold sky temperature tsysmin=tskymin+tr tsys=tsky+tr dgrd=-10.0*log10(tsys/tsysmin) + dbMoon 900 ElMoon0=Elmoon ntsky=nint(tsky) auxHA = 15.0*(LST-auxra) !HA in degrees pi=3.14159265 pio2=0.5*pi call coord(pi,pio2-lat/rad,0.0,lat/rad,auxha*pi/180.0, + auxdec/rad,azaux,elaux) AzAux=azaux*rad ElAux=ElAux*rad return end