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Photo: S-Ky photography

You would think that we’d know how thunder and lightning work by now. But researchers still puzzle over what, exactly, causes those bright flashes of electrostatic discharge. Lightning electrifies the sky about 100 times per second in various locations around the world, yet the electric fields within thunderclouds seem to have only about a tenth of the strength required for producing a lightning bolt, LiveScience reports.

As it turns out, lightning may have extraterrestrial origins.  This idea is not new:

More than 20 years ago, physicist Alex Gurevich at the Russian Academy of Sciences in Moscow suggested lightning might be initiated by cosmic rays from outer space. These particles strike Earth with gargantuan amounts of energy surpassing anything the most powerful atom smashers on the planet are capable of.

Cosmic rays slamming into air molecules may split those molecules into many electrons, which collide in turn with additional molecules, snowballing into more and more electrons zipping around. Gurevich called this “a runaway breakdown,” LiveScience writes.

In a new paper, Gurevich and colleagues analyzed radio pulses from around 3,800 lightning strikes. They hypothesize that thunderclouds’ highly electrically charged water droplets and ice nuggets allow even the most un-energetic cosmic rays to spark a bolt of lightning if it comes into contact with such a cloud. Researchers know that cosmic rays hit the planet about as frequently as lightning strikes, LiveScience writes, so the theory at least makes sense.

Unfortunately, Gurevich and a number of other scientific groups are still in the process of taking simultaneous measurements of cosmic ray’s energetic particles and the radio pulses lightning produces, which should help determine whether or not the two phenomenon are indeed linked. At least for now, Gurevich’s idea—long ignored by science—is at least being given the attention needed to prove once and for all whether lightning does have extraterrestrial origins.

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Over the past few decades Lake Urmia in Iran has steadily dried up. Photo: Google / Landsat 

Since 1972, the U.S. has flown a series of satellites known as the Landsat program, a fleet of Earth-observing satellites that were tasked with taking pictures from space. Landsat’s gorgeous photos have been a favorite of the Earth-as-art crowd, and the satellites’ observations have provided an absolutely critical long-term record of how our planet is changing.

The development of Dubai, United Arab Emirates. Photo: Landsat / Google

Today, Google put out the Earth Engine, a fascinating tool that showcases a scrollable, zoomable time-lapse of the entire planet as seen by Landsat over the decades. The Landsat photos only go back to 1984, but they show the dramatic ways in which the planet has changed in such a brief period of time. To help you get started, Google pulled out some highlights to look at, such as the drying of the Aral Sea or the deforestation of the Amazon. But the tool does show the whole planet (just the land, not the oceans), and there are many more cool things to be seen.

NASA’s Earth Observatory has a more detailed look at this, the development of the oil sands project in Alberta, Canada. Photo: Landsat / Google

But don’t bother looking for Antarctica, because it’s not included. (Sad.)

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A modern day foraminiferan species. Photo: Scott Fay

Researchers have discovered a jackpot of ancient DNA buried under 5,000 meters of Atlantic water and the sea floor, ScienceNOW reports. The genetic material once belonged to single-celled sea animals that lived around 32,500 years ago. This is the first time ancient DNA has been recovered from such oceanic depths.

The researchers uncovered the samples from silt and clay deposits. They analyzed their samples for traces of DNA specific to two groups of single-celled organisms—foraminifera and radiolarians—using genetic sequences from modern, related organisms to identify the DNA they were after. Their analysis turned up 169 foraminifera and 21 radiolarian species, ScienceNOW reports, many of which are new to science.

Where there is some DNA, the researchers reason, there must be more.  If they’re correct, the deep sea could constitute a treasure trove of long-buried DNA waiting to be discovered. Such DNA, the team told ScienceNOW, expands scientists’ ability to study ancient biodiversity.

Significantly, the existence of some of these newly discovered species isn’t well documented in the fossil record. Since fossils only preserve animals with hard structures—bones, shells, exoskeletons—DNA preserved in the vast stretches of the ocean floor could provide a unique view of animals otherwise lost to the millennia.

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In February 2013 Cassandra Brooks, a marine scientist with Stanford University, landed at McMurdo Station, a U.S. research station on the shores of Antarctica’s Ross Sea. For two months she worked on a ship, the icebreaker Nathaniel B. Palmer, cruising through the Antarctic sea. Brooks documented her life on the ship for National Geographic, and now she’s compiled two months of travels into a gorgeous time-lapse video. It gives a rare look at the onset of the fall season in one of the most remote places on Earth.

Don’t miss the end, where Brooks’ camera caught the ebb and flow of penguins going out to fish—a odd scene to watch in time-lapse.

Brooks’ cruise was intended to track what happens to all the phytoplankton that grow in the Ross Sea during the summer as the sun sets for the long polar winter.

This isn’t the only time-lapse that Brooks has put together, either. Here she shows what its like to do science from the ship as they cruise the Ross Sea.

H/T Deep Sea News via BoingBoing

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A funnel cloud in Texas. Photo: Charleen Mullenweg

For two years the majority of the continental U.S. has been plagued by drought, a confluence of natural cycles that have worked together to drive up temperatures and dry up the land. But for all the damage that has been done by the long-running drought, there’s been an upside as well. The lack of water in the atmosphere has also sent the U.S. toward a record low for tornadoes, says Climate Central‘s Andrew Freedman.

The National Severe Storms Laboratory (NSSL) in Norman, Okla., estimates that, between May 2012 and April 2013, there were just 197 tornadoes ranked EF-1 or stronger on the Enhanced Fujita scale. That beats the previous 12-month low, which was 247 tornadoes from June 1991 and May 1992.

That’s the lowest recorded tornado activity since 1954, when scientists first really started keeping track. The number of deaths connected to tornadoes went down, too:

The U.S. did set a record for the longest streak of days without a tornado-related fatality — at 220 days — between June 24, 2012 and Jan. 26, 2013. And July 2012, which was the hottest month on record in the U.S., saw the fewest tornadoes on record for any July.

But the tornadoes didn’t just up and disappear, says Freedman in an August story. Rather, some of them just moved to Canada.

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