If the universe is 15 billion years old and expanding and the speed of light. Then thats a sphere 30 billion light years in diameter.
V=4/3¶r3= (15e9)e3 * 4/3 * ¶ = 1.41371669 × 10e31 cubic light years
Let say our solar system is the distance from pluto to the sun thats
5.869 e9 miles
1 light year = 5,865,696,000,000 miles
5.869 e 9 / 5.865696e12 = 0.00100056328 light years
v= (0.00100056328)^3 * pi * 4/3 =4.19587258 × 10-9 cubic light years in our solar system.
How many volumes in the universe the size of our solar system.
1.41371669 × 10e31 /4.19587258 × 10e-9
3.36930321× 10e39
If we can scan 1,000,000,000 of those volumes in one second that means it would take :
365.25 x 24 x 60 x 60 x 1000000000 = 3.15576 × 10e16
3.36930321× 10e39 / 3.15576 x 10e16 = 1.06766776 x 10^23 years
I give up no f***ing way you peeps can understand how big the universe is.

Yes it's a big place, yes there are a lot of planets out there, but we still know so little about how life started (outside of useless unprovable theories). Who is to say that life doesn't start up in every single star system with planets like ours? Wow, the stupidity of those equations absoutely astounds me. What exactly are you proving? That you can cut and paste from a science website with no real understanding of what it proves? Really annoying and pathetic tbh. 1,000,000,000 systems? Post back when we've "scanned" just 100 of those.