To simplify the expression \((4 \times 10^{-9})^5\), we will apply the property of exponents \((a \times b)^n = a^n \times b^n\).
Here, we break it down as follows:
\[ (4 \times 10^{-9})^5 = 4^5 \times (10^{-9})^5 \]
Calculating \(4^5\):
\[ 4^5 = 1024 \]
Calculating \((10^{-9})^5\):
\[ (10^{-9})^5 = 10^{-45} \]
Now, we can combine these results:
\[ (4 \times 10^{-9})^5 = 1024 \times 10^{-45} \]
Next, we need to express \(1024\) in scientific notation. \(1024\) can be rewritten as:
\[ 1024 = 1.024 \times 10^3 \]
Now, substituting back into our expression gives:
\[ 1.024 \times 10^3 \times 10^{-45} \]
When multiplying the powers of ten, we combine the exponents:
\[ 1.024 \times 10^{3 - 45} = 1.024 \times 10^{-42} \]
Thus, the simplified form in scientific notation is:
\[ \boxed{1.024 \times 10^{-42}} \]