I programmed the flight software interface to those laser rangefinders. While they are beasts, they were very touchy in testing. I've sinced moved on to other jobs, but I was still quite nervous that they would fail on descent. I was texting members of the team asking them to check that the lasers were working in orbit. I was horrified to hear that they weren't responding. I thought my software had failed or worse, damaged the lasers. Hearing that NDL was going to be used instead was an immense relief to me. What's more, we've now qualified NASA's planned landing instrument to TRL 9!<p>I should also add that from my very first phone call with members of the software team, we clicked. It's an absolutely gobsmacking group of hard working, brilliant, experienced, and yet still inquisitive and passionate people! I've never met a finer team and it was an honor to be able to play a very small part in all this.