Illustration: Christoph Niemann
How worried should I be about a giant meteor hitting Earth and wiping out our species?
When you lie awake at night imagining an asteroid hurtling toward our planet to sucker punch humanity like it did the dinosaurs, you should picture a space rock at least a mile across. That is, if you care about having scientifically accurate anxiety. The surprise meteor that exploded over Russia this past February, blowing out windows and releasing nearly 500 kilotons of energy, was about 60 feet across. The rock that took out the dinosaurs 65 million years ago? A whopping 6.2 miles wide.
Don Yeomans, manager of NASA's Near Earth Object program and the reigning expert on city-killers and civilization-enders—says "the dividing line between an object that would cause regional damage and one that would cause global damage isn't drawn very clearly, but anything 1.2 miles or larger would cause global problems and potentially a mass-extinction event." Once you get to objects that size, the stuff kicked up by an impact would rise into the atmosphere and create "firestorms, acid rain, and loss of sunlight," as well as a blast wave, tsunamis, and local earthquakes. But before you start saying farewell, understand the chances of a large asteroid hitting Earth. "Statistically, it's every million years," Yeomans says. (He assures us we're not overdue.) He points out that NASA is already tracking 95 percent of the near-Earth objects that are 0.6 mile across or bigger. Of course, though a giant asteroid strike is unlikely, Yeomans adds, even a smaller one could have a huge effect. Sleep tight!
How do I politely get off an email chain once the idiots on it are sending a million messages a day?
Ah, the group Reply All—the most effective tool for turning your friends and acquaintances' messages into spam. As with all ejunk, the rational response might be to stay calm and delete, but even spammers don't send 15 emails every five minutes soliciting your opinion on how best to coordinate the schedules of a dozen adults trying to meet for karaoke. If a messy room can have a deleterious effect on one's state of mind, so too can the sloppy, swamped inbox. Chain emails destroy inbox feng shui. It can be hard to stay rational.
To extract yourself from an endless thread, honesty is not the best policy. You want less fuss, not more, and calling attention to your annoyance is fussy as hell, not to mention rude. No, you want to pull off the equivalent of leaving a party without saying good-bye: You want to ghost. To effect your escape, you need an accomplice, a friend you can ask for a favor, as in "next time you Reply All, would you be so kind as to surreptitiously drop me from the cc?" Ta-da: You're free of well-meant spam, and no one is the wiser. If someone notices your absence, you can always feign "how did that happen?" If, unfortunately, you don't have a trusted pal and worry that staying on the chain will make you think less of the other participants permanently, well, that's what custom email filters are for.
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How should I choose avatars for all my social media? Should I just use the same one for Tumblr, Twitter, Facebook, Instagram, and so on?
Avatars are all about branding—yourself. Gross, but it's true. "Your profile photo is a reflection of your personal brand," says Sara McKinley, a product manager at Google Plus. Didn't know you had a personal brand? Well (a) you do and (b) it's really just a slick way of saying that your avatars are communicating something, so you want to control the message. After all, it's likely many people see your avatars more often than they see you.
Keep in mind your audience on each network. Are you a Facebook user with friends you actually know, or one who wants his friend total to rival the population of a small city? Instagram is more intimate than Twitter, which gives strangers a sense of your personality (as opposed to your rè9sumè9 on LinkedIn). Keep things simple, says Zack Sultan, a designer at Tumblr: "Be bold but go for as little detail as possible. This thing's got to read at 16 by 16 pixels." Pick a strong, clean graphic or a good, well-lit picture of yourself. If you're going to use a different picture for every network, don't cross streams: An artsy photo makes sense on Instagram but seems pretentious on Twitter. Whatever avatar you choose, you should be comfortable imagining your parents, friends, significant others, colleagues, strangers, ex-friends, ex-significant others, and future bosses giving it a good, hard look. Because they will.
