The grid fins on the outer cores are aluminium, the centre core is titanium. Newer Falcons will have titanium grid fins (the outer cores have already flown once before)
Edit. Looking closer I'm wrong - the titanium grid fins are on the side boosters and the the centre core is aluminium
>> They will launch Musk's Tesla Roadster into orbit around the sun, where it will continue orbiting for hundreds of millions of years.
Good god that's funny. I didn't realize the roadster was going anywhere, so it seemed stupid. But just imagine once people forget about this in 50 years. Perhaps we even have people on mars. But every few years someone post to the equivalent of HN a link to a wikipedia article about this car orbiting the sun... Or what if modern society suffers a setback (an actual nuclear war or something) and knowledge of this is forgotten and centuries hence, people redevelop technology and get images of it. Best joke ever.
Wouldn't be the first time we rediscovered something we shot out there and sorta forgot about.
If I recall correctly, a few years ago an astronomer detected something drifting pretty far away with weird visual characteristics. It turned out to be a big piece of metal discarded from one of the Apollo missions, painted white, still tumbling through space.
Or we succeed with the path we're starting to tread. And in less than a century there's a museum built around the car where people of all sorts, some perhaps even born on different planets, are free to visit and observe what would be utterly symbolic of the advent of private industry and deep space.
Perhaps I should have chosen a better example, argument order is just an illustration.
In 1998 the Mars Climate Orbiter[0] failed because of a fairly simple software error - an imperial value was treated as metric causing the spacecraft to calculate an invalid trajectory and burn up on entry to Mars orbit. This bug was not detected in testing.
With opaque types this could never have happened, it would have produced a compiler error long before the bug ever made it into production. They eliminate an entire category of bugs.
I have come across a need for this in typescript and have used similar approaches as the author. Maybe this is a bad outlook of mine, but I am tending more and more to trusting my tooling over some of my fellow developers.
Is this repeatable though? It seems like this could be explained by a combination of the Frequency Illusion / Baader-Meinhof Phenomenon[0] and the Birthday Problem[1].
That is - it is possible that the reason you were discussing the topic is the same reason that advertisers were targeting that particular phrase at that time. The Frequency Illusion could explain why you noticed that particular ad and why you were surprised. Also you presumably discuss topics all the time that you don't see ads for, but the probability of seeing an ad for any of those topics is quite high (the birthday problem).
[1] https://en.wikipedia.org/wiki/SpaceX_COTS_Demo_Flight_1#Addi...