Phil Plait of Bad Astronomy can help you understand this miracle of the cosmos. His post on 10 Things You Didn't Know About Comets does include some things I already knew—the whole "comets are basically dirty snowballs" bit—but there's plenty of wonderful new-to-me-anyway knowledge to make up for it.
For instance, that circled dot in the image up there? That's Halley's Comet, as photographed in 1982, while it was out on the far side of Saturn. Notice how there's just a dot, and no big, long tail? That's not a misleading trick of space photography. When they're far enough away from the sun, comets lose their snowball slushiness and freeze down into tiny, solid balls.
Comets tend to have long, elliptical orbits. The farther they are from the Sun, the slower they travel, so really they might spend 99.9% of their lives far, far from the heat of our nearest star. That in turn means that all that volatile stuff in the nucleus is frozen, and actually it gets so cold that even the water freezes into ice harder than rocks on Earth.
Bad Astronomy: 10 Things You Don't Know About Comets
For more about this Halley pic, visit the Smithsonian Air and Space Museum.
Thirty years ago today, the Voyager 1 spaceprobe had completed its ncounters with the outer planets and was careening out of our solar system. The time came to shut off the probes’ cameras to preserve power and memory for the other onboard scientific instruments. But before engineers flipped the switch, one last photo opportunity was […]
While scientists have studied Moon rocks for 50 years, researchers have for the first time conducted deep analysis on a single grain of lunar dust, atom by atom. Using a common materials science technique called atom probe tomography that’s not widely used by geologists, the Chicago Field Museum’s Jennika Greer and colleagues probed the grain […]
This is so amazing. Watch what happens when a blacksmithing anvil is lowered into a large vat of pure liquid mercury. Update: One of our readers posted the link to the original video in the comments. I have replaced the animated GIF. Thanks, Crispy75. [H/t Alberto Gaitán via Bryce Lynch] Image: Screengrab from GIF
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For those with a writing flair, the thought of building a career as a professional copywriter should probably have some appeal. Thankfully, it’s also an in-demand job skill with the average copywriter making a healthy $60,000 a year for their efforts. But even if you have a way with words, you still need the industry […]
While we all love our iPhones and iPads, celebrating the releases of their latest and greatest versions, it’s amusing to consider how much we at the same time HATE the main item that keeps these little tech marvels powered up and working. No, Lightning cables don’t exactly inspire feelings of awe and wonder. It’s more […]