Sure, I too am a little tired of the all the time-lapse photography on the internet these days. However, my love for clouds (I’m a long time member of the Cloud Appreciation Society) had me going gaga over this video called “Test D” by sixdegreesbelowthehorizon. Be sure to go full screen with this one.
A lightning storm in Venezuela has been raging with incredible consistency since at least 1595. Known as “Relámpago del Catatumbo”, this mysterious storm located on the mouth of the Catatumbo river at Lake Maracaibo sees an estimated 1,176,000 electrical discharges per year. The lightning is a cloud-to-cloud arc that forms for 140 to 160 nights a year, 10 hours a night, and as many as 280 times an hour for centuries.
In fact, the lightning, visible from 400 kilometers away, is so regular that it’s been used as a navigation aid by ships and is known among sailors as the “Maracaibo Beacon.” Interestingly, generally little to no sound accompanies this fantastic light show, as the lightning moves from cloud to cloud—far, far above the ground.
(Image courtesy of University Of Florida Lightning Research Group)
How lightning works is still pretty much a mystery. But this summer, some large steps to understanding it’s movement were made. Until recently, there wasn’t fast enough camera technology to capture an x-ray image of lightning.
A new camera has a resolution sharp enough to reveal a bright ball of x-rays at the head of the bolt, with almost no lingering radiation along the bolt’s trail. The X-ray glow follows a so-called lightning leader – a channel in the air that forms a path for the lightning. The leader’s charged tip creates an electric field that accelerates electrons almost to the speed of light and causes the X-ray emissions.
The lightning leader is also known as a step leader, because it seems to travel by leaps and bounds rather than in a continuous line. The trail left by the step leader allows negative charge to travel down, even as positively charged leaders travel upward from the ground to meet in the middle. That triggers a so-called return stroke moving upward from the ground toward the cloud – the flash of what human eyes see as lightning.
You can find a lot more lightning stuff on Artifacting.
Over the next two days some areas of Colorado Rockies are expecting up to eight feet of snow. Avalanche danger is already high and expected to get much worse. Be careful out there folks.
Being caught in an avalanche is like being buried in cement. You can’t dig yourself out of an avalanche. When buried, you can’t even move. Even if you could move, which you can’t, you wouldn’t know which way is up. And although it may be cold being buried in the snow it is actually suffocation that kills you. Your only chance of survival is if your friends (you are with friends right?) dig you out.
The first person video below gives you an idea of what it might be like to be caught in an avalanche, and being rescued.
The scratching/ruffling back-and-forth sound you hear is his chest rising and falling and the noise that his jacket makes. You can actually hear his breathing become stressed and accelerate, even in the short amount of time he was buried. The intermittent whimpering noise you hear is him trying to swallow and get some air.
He was only buried for 4 and a half minutes which is incredibly short. I cannot stress these next sentences enough; that in and of itself to be unburied in ONLY 4:28 is miraculous if you have any understanding of being caught in an avalanche and what it takes to be found. It could literally be some kind of “world record” just on how good the guide and supporting cast of other skiers was in getting to him.
Have some fun out there but respect nature.
The annual summer Perseid meteor shower is set to display its glory in our skies over the next couple of days. The show comes as Earth passes through the dust trail of the Swift-Tuttle Comet. The meteors that scorch through the atmosphere appear to come from the constellation Perseus. The peak of the show is expected to be this evening, Thursday the 12th of August. The show should be particularly easy to view this year since there will be little light interference from the moon.
If you go outside a little early on Thursday evening, around sunset, you’ll see a beautiful gathering of planets in the sunset sky–Venus, Mars, Saturn and the crescent Moon. It’s a nice way to start a meteor watch. Here are a few tips to help you have the best viewing experience.
- Check the weather. If it’s cloudy in your area there’s no point to the rest of it. Checking the weather will also let you know if you should bring a coat or warm clothes.
- Clear Sky Charts are a good way to determine how dark and cloudy your night sky will be. For example, here is the chart for Denver:
- Try to get out of the city. Your viewing experience is greatly diminished by light pollution: the leftover glow leaked from densely populated cities’ artificial light. Use this website to help you determine the darkest place for viewing in your area.
- Use this website to help you determine the peak time for viewing in your timezone. The best Perseid activity, no matter the date or location, is usually seen during the last hour before the start of morning twilight, when Perseus lies highest above the horizon in a dark sky. This is usually between the hours of 4:00 AM and 5:00 AM for most of us. If you can’t time it exactly don’t worry, anytime after midnight you should see a healthy number of “shooting stars” throughout the night.
- The meteors will appear to be coming from the near the Persius constellation. So try to find a location with a low horizon to the north-northeast (if you are in Northern hemisphere). It’s not important that you look precisely at the Persius constellation but a goodstar chart will help you orientate yourself to the heavens and give you an idea of what you are looking at. Sky maps can also be found online and for the iPhone.
- Relax your eyes and let you gaze wander this will allow you to pick up on the quick flashes that are produced by the shower.
- A coat or blanket
- A flashlight
- A compass (or a good sense of direction)
- A folding lounge chair
- Drinks & snacks
- A sense of wonder
Things to bring:
Most of all it’s important to have fun and enjoy the splendors of nature. If you’re interested in learning more about meteor showers this amateur astronomy website is a good place to start.
Less than two seconds in real-time, this video of a lightning strike in Rapid City, South Dakota is spectacular. The video is slowed down to 9,000 frames per second. ZT Research describes the video as a preceding downward positive ground flash that triggers upward leaders from seven towers, three of which are visible in the video. I love how hundreds of “mini strikes” flicker around the central strikes. ZT Research has more cool lightning strike videos on their site.