Which type of chemical messenger do the male gonads secrete?

The answer is Androgen. An androgen is a natural or synthetic steroid hormone which regulates the development and maintenance of male characteristics invertebrates by binding to androgen receptors.

Not what goes around on earth but the universe too.

F  you double the  force, you double the acceleration, but  if  you double the  mass, you velocity. all bodies accelerate at the  same  rate regardless of size or  mass.