discovered the Americas or sailed around Africa or proved the world was round nor settled the west nor flown to the moon.

We should have freedom to enter into employment. If Elon Musk wants to pay me $50 Million to fly on his spacecraft knowing that there is a 20% chance I'll die, then we both should be able to willingly enter into that contract. People did it for exploration purposes all the time hundreds of years ago. "Be a sailor on this ship! There's a good chance you'll die (you probably were going to die if you were poor anyway either from military service or malnutrition or disease), but if you do make it back your family will be rich!" And people lined up to take that offer.

As long as you are compensated fairly and both parties enter into the agreement knowingly, there is no reason for governments to stop it.