Gold is weird. It's one of the few metals that doesn’t really oxidize. Even silver and copper—from the same column of the periodic table—form weak oxides. Naively, you might expect that gold would tarnish just like silver. Gold also sits right next to platinum, but it has none of that metal’s catalytic properties.

Then came gold nanoparticles that acted like catalysts, and we were confused by their apparent willingness to take part in chemical reactions.

Now, a pair of scientists has explained that gold’s inertness isn’t inherent to the atom but rather to the surfaces that gold crystals form. Before we get to the results, let’s first take a look at the traditional explanation for gold’s inertness and why an inert material that has no catalytic activity suddenly acts as a catalyst when in its nanoparticle form.

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The Federal Communications Commission has waived a requirement for Amazon to launch half of its satellite broadband constellation by the end of July, a key regulatory reprieve that buys the tech giant time to get more of its spacecraft into orbit.

Amazon won regulatory approval for the Amazon Leo network in July 2020. The FCC's authorization came with two deadlines. First, Amazon had to launch half of its 3,232 satellites by July 30, 2026, in order to maintain authorization to launch the rest of the network. The regulator gave Amazon a deadline of July 30, 2029, to have all of its first-generation satellites in orbit.

It has been apparent for some time that Amazon would not meet the FCC's requirement to launch half of its satellites—1,616 spacecraft—by the end of next month. Amazon filed an application in January requesting the FCC extend the deadline to July 2028 or waive it altogether. The commission decided on the latter option, removing any time limit for the 50 percent deployment milestone, but keeping the July 2029 deadline in place for the entire constellation.

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