Month: December 2017

Video shot by Joshua Ballinger, edited and produced by Jing Niu and David Minick. Click here for transcript. (video link)

First, it took the acceptance of risk for NASA to fly into space—and to return to flight after three astronauts died. Then, it took guts to send astronauts on a round trip into lunar orbit and back. But in 1969, after years of increasingly frenetic activity, the efforts of nearly half a million men and women were finally rewarded with the ultimate trip: a safe lunar landing and return, before the end of the decade.

Apollo 11 is special—not just to the history of NASA or the United States of America, but for the entire world and all live on her. On a plain summer day in July of 1969, just past three o'clock in the afternoon Houston time, three humans landed a fragile spacecraft with paper-thin walls on another world. It was to be the first time humans walked on a celestial body other than our home—and, for a few hours, we as a species were more than Americans and Soviets and Chinese and Britains and so on. Those three people boldly making footprints where no one had gone before showed us that we truly were, as Apollo 8's Frank Borman put it, all people of "the good Earth."

Video shot by Joshua Ballinger, edited and produced by Jing Niu and David Minick. Click here for transcript. (video link)

Working outside a spacecraft in a spacesuit—or walking on the Moon in one—is among the most dangerous activities that an astronaut can take part in. Officially referred to as "EVA" in NASA acronym shorthand—that's short for "extravehicular activity"—and commonly called "spacewalking" by the public, leaving the pressurized metal protection of your ship or station and floating in the void means committing yourself to a dynamic environment where conditions can change very rapidly. EVAs typically last a few hours but require months of training in the agency's giant swimming pool to ensure everything goes well.

The capstone activities of Apollo were the surface EVAs, where astronauts planted flags, placed experiments, drove space cars, and otherwise tried to cram as much activity into very short windows of time. It's difficult to come up with a meaningful estimate for the per-minute cost of each lunar EVA, but estimates in the millions of dollars per minute aren't far off; with that kind of cost pressure, Apollo astronauts on the lunar surface had to do everything they could to maximize the impact of each trip outside the lunar module.

Enlarge (credit: The Matrix / Aurich)

Update, 12/26/20: It's the year end holiday season, and Ars staff has been enjoying some much needed downtime. While that happens, we're resurfacing some classic Ars stories like this 2017 explainer on everything you've wanted to know about Bitcoin but may have been afraid to ask. (Because with the cryptocurrency's value reaching a new record high not even two weeks ago, it's perfectly reasonable to want the basic intel.) This piece first published on December 15, 2017 and it appears unchanged below.

The soaring price of bitcoin—the virtual currency is now worth more than $250 billion—has gotten a lot of attention in recent weeks. But the real significance of bitcoin isn't just its rising value. It's the technological breakthrough that allowed the network to exist in the first place.

Bitcoin's still anonymous inventor, who went by the pseudonym Satoshi Nakamoto, figured out a completely new way for a decentralized network to reach a consensus about a shared transaction ledger. This innovation made possible the kind of fully decentralized electronic payment systems that cypherpunks had dreamed about for decades.

Enlarge (credit: Tech.co)

Today, America Online Instant Messenger, better known by its acronym, AIM, went dark after more than two decades of faithful service.

Those of us who came of age in the 1990s and early 2000s fondly remember the halcyon days of chat rooms, lolspeak, and away messages. We know that, while some of the Ars audience were 1337 sysops on IRC channels, for a lot of us, AIM was the primary way to connect with our friends online across town and around the globe.

We asked readers on Twitter: would you share your AIM memories with us? Just a few sentences of what you remember most, what you got out of it, what, if anything, it taught you? The responses have been lightly edited for length and clarity.