On Jupiter, lightning jerks and jolts a lot like it does on Earth. 



New views of storms on Jupiter hint that its lightning bolts build by lurching forward. Whats more, those staggering steps happen at a similar pace to lightning bolts on our own planet. 



Arcs of lightning on both worlds seem to move like a winded hiker going up a mountain, says Ivana Kolmaov. A hiker might pause after each step to catch their breath. Likewise, lightning on Earth and Jupiter both seem to build by one step, another step, then another, Kolmaov says. Shes an atmospheric physicist at the Czech Academy of Sciences in Prague. Her team shared the new findings May 23 inNature Communications.  





The discovery about Jupiters lightning doesnt just offer new insights into this gas giant. It could also help aid in the search for alien life. After all, experiments hint that lightning on Earth could have forged some of the chemical ingredients for life. If lightning works a similar way on other worlds, it might produce lifes building blocks on distant planets, too. 



Lightning, step by step 



Here on Earth, winds within thunderclouds whip up lightning. The winds cause many ice crystals and water droplets to rub together. As a result, those tiny bits of ice and water become electrically charged. Bits with opposite charges move to opposite sides of the clouds, building up charge on either end.  



Lets learn about lightning



When that charge buildup gets big enough, electrons are released the lightning takes its first step. From there, the surging electrons repeatedly rip electrons off molecules in new segments of air and rush into those segments. So the bolt of lightning leaps forward at tens of thousands of meters per second, on average. 



Scientists thought Jupiters lightningmight also form by ice crystals and water droplets colliding. But no one knew whether the alien bolts grew step by step, as they do on Earth, or if they took some other form. 



Views from Juno 



Kolmaovs group looked at data from NASAs Juno spacecraft. Specifically, they looked at pulses of radio waves given off by Jupiters lightning. The data included hundreds of thousands of radio wave pulses from lightning over five years. 



Radio waves from each lightning bolt seemed to happen about once per millisecond. On Earth, lightning bolts that stretch from one part of a cloud to another pulse at about the same rate.This hints that Jupiters lightning builds in steps that are hundreds to thousands of meters long, too. 







Step-by-step lightning is not the only possible explanation for what Juno saw, says Richard Sonnenfeld. Hes an atmospheric physicist who wasnt involved in the study. He works at the New Mexico Institute of Mining and Technology in Socorro.   



The radio pulses could have come from electrons running back and forth along bolts of lightning, Sonnenfeld says. On Earth, such currents cause some bolts to appear to flicker. Still, he says, stop-and-go lightning formation is a perfectly reasonable explanation for the data. 

Its common to hear the term chaos used to describe seemingly random, unpredictable events. The energetic behavior of kids on a bus ride home from a field trip might be one example. But to scientists, chaos means something else. It refers to a system that is not totally random but still cannot be easily predicted. Theres a whole area of science devoted to this. Its known as chaos theory.



In a non-chaotic system, its easy to measure the details of the starting environment. A ball rolling down a hill is one example. Here, the balls mass and the hills height and angle of decline are the starting conditions. If you know these starting conditions, you can predict how fast and far the ball will roll.





A chaotic system is similarly sensitive to its initial conditions. But even tiny changes to those conditions can lead to huge changes later. So, its hard to look at a chaotic system at any given time and know exactly what its initial conditions were.



For example, have you ever wondered why predictions of the weather one to three days from now can be horribly wrong? Blame chaos. In fact, weather is the poster child of chaotic systems.





The origin of chaos theory



Mathematician Edward Lorenz developed modern chaos theory in the 1960s. At the time, he was a meteorologist at the Massachusetts Institute of Technology in Cambridge. His work involved using computers to predict weather patterns. That research turned up something strange. A computer could predict very different weather patterns from almost the same set of starting data.



But those starting data werent exactly the same. Small variations in the initial conditions led to wildly different outcomes.



To explain his findings, Lorenz likened the subtle differences in starting conditions to the impacts of the flapping wings of some distant butterfly. Indeed, by 1972 he called this the butterfly effect. The idea was that the flap of an insects wings in South America might set up conditions that led to a tornado in Texas. He suggested that even subtle air movements such as those caused by butterfly wings could create a domino effect. Over time and distance, those effects might add up and intensify winds.



Does a butterfly really affect the weather? Probably not. Bo-Wen Shen is a mathematician at San Diego State University in California. This idea is an oversimplification, he argues. In fact, the concept has been generalized mistakenly, Shen says. Its led to a belief that even small human actions could lead to huge unintended impacts. But the general idea that tiny changes to chaotic systems can have huge effects still holds up.





Maren Hunsberger, a scientist and actress, explains how chaos is not some random behavior, but instead describes things that are hard to predict well. This video shows why.



Studying chaos





Chaos is difficult to predict, but not impossible. From the outside, chaotic systems appear to have traits that are semi-random and unpredictable. But even though such systems are more sensitive to their initial conditions, they do still follow all the same laws of physics as simple systems. So the motions or events of even chaotic systems progress with almost clock-like precision. As such, they can be predictable and largely knowable if you can measure enough of those initial conditions.



One way scientists predict chaotic systems is by studying whats known as their strange attractors. A strange attractor is any underlying force that controls the overall behavior of a chaotic system.



Shaped like swirling ribbons, these attractors work somewhat like wind picking up leaves. Like leaves, chaotic systems are drawn to their attractors. Similarly, a rubber ducky in the ocean will be drawn to its attractor the ocean surface. This is true no matter how waves, winds and birds may jostle the toy. Knowing the shape and position of an attractor can help scientists predict the path of something (such as storm clouds) in a chaotic system.



Chaos theory can help scientists better understand many different processes besides weather and climate. For instance, it can help explain irregular heartbeats and the motions of star clusters.

Massive Otodus megalodon sharks the oceans largest meat-eaters ever ran hot. It now appears that their rise (and fall) may have been tied to their warm-bloodedness.



Chemical measurements on fossil O. megalodon teeth suggest the sharks had higher body temperatures than surrounding waters. Analyses of carbon and oxygen in the teeth revealed that the giant sharks body temperature was about 7 degrees Celsius (13 degrees Fahrenheit) warmer than seawater temperatures at the time.





Lets learn about sharks



That warm-bloodedness may have been a double-edged sword. The trait may have helped megalodons become swift, fearsome apex predators. Those are hunters at the top of the food chain. O. megalodon grew up to 20 meters (66 feet) long. That makes it one of Earths biggest carnivores ever. But the sharks voracious appetite also may have spelled the species doom.



A creatures metabolism is the set of chemical reactions needed to sustain life. Gigantic bodies require a lot of food to power their metabolisms, notes Robert Eagle. A marine biogeochemist, he studies the chemistry of ocean ecosystems. Massive sharks may have been particularly vulnerable to extinction when food became scarce, he says. Eagle was part of a team that studied fossils of O. megalodon and its living and extinct kin to learn about the animals metabolisms.



Game over for megalodons



Mammals can boost their metabolisms and maintain their body heat, even in colder environments. This trait is called endothermy or warm-bloodedness. Some families of fish, both living and extinct, can do something similar. They can keep some body parts warmer than the surrounding water. This is known as regional warm-bloodedness. Many modern sharks belonging to the group that includes great white sharks have this ability.



Jacking up the temperatures of some body parts is one way some sharks evolved to be giant, says Jack Cooper. A paleobiologist, he studies ancient life at Swansea University in Wales. He did not take part in the new study. Filter feeding offers another path to getting large, Cooper points out. Gentler giants, such as whale sharks, use this strategy when they gulp lots of water and eat the tiny creatures within.



Scientists have long thought megalodon was regionally warm-blooded, Eagle says. Estimates of this beasts body shape, swimming speeds and energy needs point to some warm-bloodedness. The shark also was known to hunt in both colder and warmer waters. That suggests it had some control over its body temperature.





The question, Eagle says, isnt really whether O. megalodon was warm-blooded. Its how warm-blooded. His team wondered how the megasharks internal temps compared to one of its major competitors: the great white shark.



O. megalodon evolved around 23 million years ago. It went extinct sometime between 3.5 million and 2.6 million years ago. Great white sharks emerged late in megalodons reign, roughly 3.5 million years ago. They competed for food with their massive cousins.





Some scientists suspect this competition helped drive O. megalodon to extinction, especially when food became scarcer. The climate changed during the Pliocene Epoch, which spanned 5.3 million to 2.6 million years ago. That led to a sharp drop in the numbers of marine mammals. They were a primary food source for both sharks.



But the great whites stuck around when O. megalodon died out, Eagle says. Being the much smaller of the two, they likely needed less food to maintain their metabolism.



Ancient temperature check



To study the ancient sharks body temperatures, the team turned to the only fossils left by these sharks: their teeth.



Fossilized teeth can say a lot about the bodies they came from. A tooths enamel contains isotopes, heavier and lighter forms of a chemical element. Eagles team examined chemically bonded forms of heavier-than-usual carbon and oxygen. The technique acted as a kind of ancient thermometer. The abundance of bonds between these isotopes is only affected by body temperature, Eagle says.



Explainer: What are chemical bonds?



The team used this technique on teeth from great whites and megalodons. They also used it on other animals who lived at the same time. Mollusks are entirely cold-blooded; they cant control their body temperature. Analyzing ancient mollusks revealed the oceans water temperature.



Great whites and megalodons were at least somewhat warm-blooded, the team found. A megalodons body was warmer than the water around it. It also was warmer than the bodies of great white sharks. Neither shark, however, was as warm-blooded as marine mammals, such as whales.



The researchers shared their findings June 26 in Proceedings of the National Academy of Sciences.



It’s fantastic that we have more evidence for regional warm-bloodedness in megalodon, Cooper says. O. megalodons higher body temperature would have allowed it to swim further and faster, he says. That increased its chances of finding prey. But when the sharks prey dwindled some 3 million years ago, he says, megalodon may well have starved into extinction.



Eagles team is now exploring the chicken-or-egg question of which came first for megalodons: warm-bloodedness or apex-predator status. You need to be big to be a mega-predator. But its not clear whether carnivores need to be warm-blooded to become apex predators. Were hoping to fit it all together into an evolutionary story as to what drives what.