アニメーション

in=Animate[
(*back ground*)
back={
RGBColor[0.1,0.1,0.2],
Rectangle[{-2,2},{2,-2}]
};

(*firefly's light*)
firefly={
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.6,0.5-t/2,t/2-0.1]]],
Disk[{Cos[1.2t]-1,Sin[1.2t]-1},0.5],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.6,0.5-t/2,t/2-0.1]]],
Disk[{Cos[1.2t]-1,Sin[1.2t]-1},0.52],

RGBColor[0.9,0.9,0.75,If[t<0.2,0,If[t>0.6,0.4-t/2,t/2-0.2]]],
Disk[{-t-Cos[1.2t],-t+1},0.3],
RGBColor[0.9,0.9,0.75,If[t<0.2,0,If[t>0.6,0.4-t/2,t/2-0.2]]],
Disk[{-t-Cos[1.2t],-t+1},0.32],

RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.8,0.45-t/3,t/3-0.1]]],
Disk[{-t+1.8,-t/2+1.8},0.24],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.8,0.45-t/3,t/3-0.1]]],
Disk[{-t+1.8,-t/2+1.8},0.26],

RGBColor[0.9,0.9,0.75,If[t<0.05,0,If[t>0.8,0.17-t/6,t/9-0.05]]],
Disk[{t-0.5,-t+1},0.75],
RGBColor[0.9,0.9,0.75,If[t<0.05,0,If[t>0.8,0.17-t/6,t/9-0.05]]],
Disk[{t-0.5,-t+1},0.77],
RGBColor[0.9,0.9,0.75,If[t<0.05,0,If[t>0.8,0.17-t/6,t/9-0.05]]],
Disk[{t-0.5,-t+1},0.78],

RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{t/2-0.7,-t^2/10-1},0.3],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{t/2-0.7,-t^2/10-1},0.32],

RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{-t^2+1.5,t^2/10+1},0.4],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{-t^2+1.5,t^2/10+1},0.42],

RGBColor[0.9,0.9,0.75,If[t<0.1,0,t/10]],
Disk[{-1/(t+0.1)+0.5,t^(1/2)/10-1.5},0.6],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,t/10]],
Disk[{-1/(t+0.1)+0.5,t^(1/2)/10-1.5},0.62],

RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{-t+2.5,-t},0.3],
RGBColor[0.9,0.9,0.75,If[t<0.1,0,If[t>0.5,0.25-t/4,t/3-0.1]]],
Disk[{-t+2.5,-t},0.32],

RGBColor[0.9,0.9,0.75,If[t<0.02,0,If[t>0.5,0.2-t/10,t/3-0.02]]],
Disk[{Cos[t]-2,Sin[t]+1.5},0.2],
RGBColor[0.9,0.9,0.75,If[t<0.02,0,If[t>0.5,0.2-t/10,t/3-0.02]]],
Disk[{Cos[t]-2,Sin[t]+1.5},0.22],

RGBColor[0.9,0.9,0.75,If[t<0,0,If[t>0.6,0.25-t/10,t/3]]],
Disk[{-Cos[t]+0.5,Sin[t]+0.7},0.1],
RGBColor[0.9,0.9,0.75,If[t<0,0,If[t>0.6,0.25-t/10,t/3]]],
Disk[{-Cos[t]+0.5,Sin[t]+0.7},0.12],

RGBColor[0.9,0.9,0.75,If[t<0,0,If[t>0.6,0.17-t/10,t/5]]],
Disk[{-t+1.8,Sin[2t]-1.6},0.185],
RGBColor[0.9,0.9,0.75,If[t<0,0,If[t>0.6,0.17-t/10,t/5]]],
Disk[{-t+1.8,Sin[2t]-1.6},0.2]
};

(*out*)
out =Graphics[{back,firefly},{PlotRange->{{-2,2},{-2,2}}}],{t,0,1,0.004},DefaultDuration->10]