Have you thought about doing:

# repeated part
my $rp = qr!(-?\d+\.\d+E[-+]\d+)!;

my $regex = qr!^(\d+)\s(\d\d):(\d\d):(\d\d)\s
(\d\d)-(\w+)-(\d{4})\s(\d+)\s(\d+\s+\d+)\s
$rp\s$rp\s$rp\s$rp\s$rp\s$rp\s$rp\s$rp\s$rp!x;
[download]

It takes out some redundancy. You could also use a loop/join instead of repeating $rp a bunch of times.

Just a thought.