However, several times each year, Earth encounters a stream of gritty debris left in space by a passing comet, and the result is a meteor shower. On most nights a half dozen of these sporadic (random) meteors appear hourly, which is what you can expect from the meteor showers in 2017. Meteors can occur at any time on any night and appear in any part of the sky. In fact, we see a meteor's streak not because the particle is "burning up," but instead because air molecules along its path become flash-heated to thousands of degrees. That's because they strike at 30 to 70 km (20 to 45 miles) per second, and all that kinetic energy is rapidly dissipated by frictional heat. The particles themselves are not large - typically they're no bigger than big sand grains, and something the size of a pea can create a meteor that's dramatically bright. The little nuggets in Grape-Nuts cereal are a close match to the size of particles that typically create meteors in our atmosphere. Expect to shoot a lot of frames before you get this lucky.ĭerived from the Greek word meteoros (meaning "high in the air"), meteors are bits of interplanetary debris slamming into Earth's upper atmosphere at altitudes of 80 to 120 km (50 to 75 miles). He used a wide-field, 16-mm lens for a 1-minute exposure at f/2.8 with an ISO setting of 800. During the 2004 Geminid meteor shower, Alan Dyer caught a bright fireball with a tripod-mounted digital camera. The rarest of these, called a bolide, shatters into pieces during its rapid descent. If you watch the starry night sky from a dark location, a few times every hour you'll see brief streaks of light from meteors, sometimes called "shooting stars." They can catch your eye just at the limit of visibility or be dramatically bright fireballs that appear brighter than Venus and light up the nightscape around you. Everyone enjoys the brief and sometimes dazzling streaks of light from meteors, sometimes called "shooting stars." Sky & Telescope predicts that the two best meteor showers in 2017 will be the Quadrantids in early January and the Geminids in mid-December. If you have any questions (except about the graphics, as noted above), please contact Peter Hardy at 61. In addition, altering this logo in any way is expressly prohibited. Note also that if you did not receive a letter of congratulations directly from Sky & Telescope, you are not authorized to download or display our Hot Product icons. You may use the icon in your advertisements in S&T beginning with the February 2017 issue, whose materials deadline is November 8, 2016. Please note that these icons are not to be used in print or online before Tuesday, November 15, 2016, when Sky & Telescope's January 2017 issue begins arriving in subscribers' mailboxes. Right-click the image to download a publication-quality PDF file. Remember to keep the background transparent when you rasterize the image. To use these files for web, open the PDFs in Photoshop (or any other image-processing program), and rasterize the PDF to the size that you need. The full color icon should be used for all materials that aren’t black and white only.īoth files are print-ready vector images. To download a high-resolution Hot Products icon, right-click the images to the right and choose “save as” to download the PDFs to your computer. Dear Astronomy Vendor: Right-click the image to download a publication-quality PDF file.Ĭongratulations on having one or more of your products recognized by the editors of Sky & Telescope as a Hot Product for 2017!
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