Archive for March, 2015

So, yup, Cameron’s Avatar and Nickolodeon Avatar, the Last Airbender (the movie never existed. Period), actually had a common point: veggie communication networks. Yay!

In the first case, Na’vi were already physiologically equipped to connect to the Hometrees. In ATLA, both the Avatar (Aang and Korra incarnations) and Toph use the roots of an ancient Banyan Grove Tree to gain information about what happens on a different part of the world. In both cases, the overall idea was that the world, just like the trees, was one living organism where everything was connected.

Actually, the idea is not as crazy as it might sound. For a time, scientists have been aware of a mutual beneficial relationship between plants and (mycorrhizal) fungi, that grow around their roots and are known to promote overall plant growth. At the moment, they are evaluating whether they allow plants to communicate with each other to warn about coming insects attacks and, hence, prepare their chemical defense systems.

Scientists actually proposed that communication occurs through the release and detection of information-carrying chemicals that traverse the soil matrix through mycorrhizal networks (any brain analogy here?). In this sense, fungi, which are highly interconnected underground via their mycelia, conform a sort of plant Internet.

Image taken from Biology Pictures

This theory was tested by researchers from the University of Aberdeen, the James Hutton Institute and Rothamsted Research. They basically grew multiple sets of bean plants in groups. Some of these plants were connected viamycorrhizal networks, whereas others were kept purposefully isolated from the rest. Then, researchers infested single plants with aphids -a damaging insect-, and found out that clean plants connected to infected ones by the mycorrhizae built up their chemical defenses (i.e. release a chemical attractor for wasps, who feed on pesky aphids), whereas unconnected ones showed no chemical response.

There is also some evidence on airborne plant communication, i.e. veggie WiFi, so we can at least say that both Cameron and Konietzko did their homework right in this case.

Source: Ecology Letters


Hi, comicbook friends. Any fan of Warren Ellis out there? Me, I like Chris Sprouse as well, so it is only natural I enjoyed Ocean. Set 100 years from now, the story focuses on a UN special weapon inspector sent to Cold Harbor, a UN research station in orbit around Europa. Deep, under the ice surface of that moon, there is an ocean and a set of nonhuman artifacts have been discovered. I’m not going further into the plot, in case anyone wants to read it spoiler-free and also because I don’t need to. It was only natural at the time that Ellis thought of Europa as a background for his plot: the smoothness of the surface has led people to think there might be a water ocean beneath its icy crust, kept liquid by tidal acceleration. Nasa also reported detection of water vapor plumes in 2013.


However, it turns out it’s its bigger sister Ganimede who might be proven to yield an ocean first. NASA’s Hubble Space Telescope has the best evidence yet for an underground saltwater ocean on Ganymede, Jupiter’s largest moon. The subterranean ocean is thought to have more water than all the water on Earth’s surface.


And, because science is cool like that, they figured it out by observing Ganymede’s aurorae borealis. The idea behind this statement is pretty simple. Aurorae appear when plasma from a solar storm reaches Earth. Our electromagnetic field basically works like a shield that deflects particles from the storm.


The shape of the magnetic field lets some particles reach our magnetic poles, both when it moves past us and backwards,sort of like a wave in the sea that hits you when the water retreats. An excellent explanation of the full process can be watched in the following 4 minutes video.

So far, so good, but what does this have to do with Ganymede? Easy. Ganymede is the only moon in our system that has its own magnetic field and, hence, aurorae in regions circling the north and south poles of the moon. However, since it is so close to Jupiter, its own magnetic field interacts with Jupiter’s. As a result, its aurorae “rock” back and forth. The plot below, for example, shows how our geomagnetic field changes depending on Earth orbital motion due to interaction with the interplanetary magnetic field brought to you by courtesy of the solar wind (see full explanation on A Hitchhiker’s Guide to Space and Plasma Physics).


According to calculations, given the proximity of Jupiter and Ganymede, aurorae should rock up to 6 degrees. However, if a saltwater ocean were present, Jupiter’s magnetic field would create a secondary magnetic field in the ocean1 that would counter Jupiter’s field. That second field would actually suppress the rocking of the aurorae. And, ta-daaa, indeed they rock only 2 degrees according to estimations!


Scientists estimate the ocean is 60 miles (100 kilometers) thick — 10 times deeper than Earth’s oceans — and is buried under a 95-mile (150-kilometer) crust of mostly ice.


1. Dissolved salts in seawater conduct electricity, and as ocean currents move within the planet main magnetic field, they generate their own secondary magnetic field (see here).