Summary: /* What you’ll need */ A red “night vision” flashlight is essential for astronomy. If you need to read a map, check a star chart, or fiddle with your telescope or camera, you can’t use a regular flashlight. For optimal star-watching, you have to let your eyes adjust to the dark of night. This takes a few minutes, and any bright, white light resets the process, ruining your night vision. But if you use a red light specially-made for astronomy, you can still read, fiddle and find your way without upsetting your own night vision or that of the people around you. Night vision flashlights can be purchased wherever telescopes, astronomy supplies, or camping gear is sold. Most fancy camera stores have them, too. But here’s the DIY version! ==What you’ll need== * A small flashlight – use the kind with an old-school bulb, not a CF bulb or an LED array. * Red “Holiday” plastic wrap – the kind you use in the kitchen to wrap food. Major manufacturers usually brand these tinted rolls as “Holiday” wrap. The red can be difficult to find outside the winter holidays, but they are available year-round online and in well-stocked grocery stores. You can also use red gels (used in theater lighting) if you can find them. * Rubber bands * Scotch tape ==How to proceed== ”’Tear”’ off a piece of plastic wrap wide enough to fit over the business end of your flashlight with an inch or two to spare on either side. ”’Fold”’ the red plastic wrap end-over-end, making tidy squares. Continue folding (and adding more strips of plastic wrap, if necessary) until you have a square about 1/8 of an inch thick. ”’Secure it”’ to your flashlight using rubber bands and/or tape. ”’Test it”’ to make sure there are no white light leaks, and that the thickness is sufficient to preserve your night vision. ”’Do it”’ again. Make a few of these 1/8 inch thick filters and stash them. You can hand them out, or replace yours if it becomes damaged in the field. [[Category:DIY]] [[Category:Astronomy]]
Summary: [[Image:1102099113 386313c1ef z.jpg|thumb|300px|left|A Perseid streaks across the sky. Photo: Rongem Boyo/[http://www.flickr.com/photos/writemboyo/1102099113/ Flickr]/CC]] The Perseid meteor shower rolls through the sky once a year, peaking in mid-August. It’s caused by a trail of debris that travels along the orbit of the comet Swift-Tuttle, which passes the Earth every 135 years. The 2010 Perseid meteor shower runs from Wednesday, Aug. 11 to the wee morning hours of Aug. 14. The peak will be the night between the 12th and the 13th. The Perseids are famous because they are so spectacular. In optimal viewing conditions, you can see between 60 and 100 meteors per hour streaking across the northern sky during the peak. 2010 is shaping up to be a great year for the Perseids, because the moon will either be a thin sliver in the sky or below the horizon during the peak nights. ”This article is part of ”’a wiki anyone can edit.”’ If you have advice to add about tracking meteors, log in and contribute.” ==Where to look== [[Image:Perseus.png|thumb|300px|right]] The Perseid meteor shower takes place in the region of the sky around the constellation [http://en.wikipedia.org/wiki/Perseus_%28constellation%29 Perseus], hence the name. It’s primarily visible to those in the Northern hemisphere after midnight. Once you find Perseus, that’s not the only place you should be looking. That’s just the center of the shower, or the “radiant,” the point from which the streaks will appear to radiate. The easiest way to spot the radiant with the unaided eye is to look for the familiar constellation of [http://en.wikipedia.org/wiki/Cassiopeia_%28constellation%29 Cassiopeia]. She’s the bright letter W in the Northern sky. The Perseids meteors radiate from a point directly below and slightly to the left. Both Cassiopeia and Perseus rise in the Northeast just before midnight, and move towards the Zenith until dawn. [http://www.flickr.com/photos/junnn/1102192658/ Here's a photo of what to look for]. If you’re familiar with the quadrant system used by most star charts and navigation systems, Perseus is in NQ1. If you have more sophisticated equipment, dial in these coordinates: * Right Ascension: 03h * Declination: +45ยบ ===Apps=== No, really — where the hell is Perseus? If you have an Android phone, get [http://www.google.com/mobile/skymap/ Google Sky Map]. If you have an iPhone or an iPad, get [http://www.star-map.fr/ Starmap] or [http://vitotechnology.com/star-walk.html Star Walk] ==Pick a spot== Big cities, suburban sprawl and other densely populated areas cause off light pollution — that hazy man-made glow that obscures the night sky. Tall buildings and trees can obscure your views as well. If you live in the country, you’re golden. You backyard is probably a great option if you turn off all the lights in your house. Otherwise, you may have to travel to somewhere on the outskirts of town, or a nearby mountain. Avoid [http://en.wikipedia.org/wiki/The_Day_of_the_Triffids Triffid farms] and do remember that temperatures can drop considerably overnight so take an extra fleece for any young observers and a flask of coffee or hot chocolate for the walk home. Find a nearby star party or shower party — gatherings of amateur astronomers that usually take over a remote parking lot or corner of a park where viewing conditions are optimal. They are usually free and full of friendly geeks with sweet meteor-viewing gear. [http://www.astro-observer.com/ Astro-Observer] lists the biggest parties, but do some searches for your local area to find the smaller ones. Just be sure to study up on the rules (no headlights!) before you go. ==Best times== The 2010 Perseid meteor shower runs from Wednesday, August 11 to the wee morning hours of August 14th. The peak will be the night between the 12th and the 13th. [http://www.tabwin.com/perseids/ Tabwin] is a website with comprehensive lists of optimal viewing windows for every corner of the Earth (with times in your local time zone), as well as tips for locating Perseus in the sky. See all upcoming astronomy events on [http://www.seasky.org/astronomy/astronomy_calendar_2010.html Sea and Sky's calendar]. ==Pack the right gear== One essential gadget for meteor viewing is a “Star light,” or a night vision flashlight that produces a dim red glow
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