Do you know what a sleeping great white shark looks like? It’s never been seen before. Until now. A robotic submersible captured the first-ever footage of a great white taking a nap, and you can see it innocently catch some zzzs with its mouth hanging wide open. It looks maybe seven percent less frightening than a great white that’s awake.
The shark doesn’t stop swimming, though its movement slows down tremendously and its body goes into this relaxed auto-pilot mode. The great white has to keep on moving, or it would sink to the bottom and suffocate.
Discovery posted this footage from Shark Week 2016’s Jaws of the Deep and explains what’s happening below.
As NASA’s Juno mission continues to hurl itself toward Jupiter, the terrifying reality of flying close to the biggest and baddest planet in our solar system is starting to set in. Yesterday, the Jet Propulsion Laboratory dropped recordings the spacecraft created based on data it collected as it crossed Jupiter’s “bow shock” and entered the magnetosphere. They’re straight-up nightmare fuel.
The bow shock is essentially the outer gate to Jupiter’s magnetic field. As charged particles (called the solar wind) approach this invisible shield at supersonic speeds, they’re heated up and slowed down, producing something akin to a sonic boom. It took Juno about two hours to cross this threshold.
The next day, on June 25th, Juno officially crossed over from the Sun’s magnetic field into Jupiter’s domain. This is basically what I imagine flying into Hell sounds like:
These recordings are but an early taste of what’s to come for the most daredevil planetary science mission ever built. On July 4th, Juno will fire its main engine, slow down from a rip-roaring 165,000 miles per hour to a slightly more modest velocity, and enter orbit around Jupiter. A few months later, it’ll be skimming the gas giant’s polar cloud tops and snapping photos of the largest geomagnetic storms in the solar system at an altitude as low as 3,100 miles, all while getting walloped by the gas giant’s powerful radiation belts.
We’ll be keeping a close eye on the spacecraft’s progress over the days to come, so stay tuned.
If you want to see beautiful auroras, forget Alaska, Canada, and Iceland—check out Jupiter. At the gas giant’s north pole, the most powerful and luminous northern lights in the solar system shimmer and glow in an endless geomagnetic storm that’s larger than our entire planet.
Jupiter’s glorious auroras—caused by the gas giant’s enormous magnetic field reeling in charged particles from the solar wind—were first discovered by the Voyager spacecraft in 1979. They’ve been studied so intensively over the past few decades that “Jovian space weather scientist” has become a bonafide sub-discipline of astronomy. Now, the Hubble Space Telescope has captured some of the most vivid images yet of this exotic space weather display.
With its ultraviolet capabilities, Hubble has been been observing the dance of Jupiter’s northern lights for about a month. The timing of this observational campaign is no accident. In less than week, NASA’s Juno mission will arrive in Jupiter’s orbit for a dangerous, year-and-a-half long mission that seeks to map the gas giant’s magnetic field, study its interaction with the solar wind, and determine the origin of the auroras.
“These auroras are very dramatic and among the most active I have ever seen”, the University of Leicester’s Jonathan Nichols said in a statement. “It almost seems as if Jupiter is throwing a firework party for the imminent arrival of Juno.”
If you were soaring through Jupiter’s turbid skies wearing a pair of x-ray goggles, you might get lucky and witness something incredible. Brilliant flashes of light, more luminous and powerful than the Sun, occurring every 26 minutes and stretching as far as the eye can see. That’s the essence of a massive solar storm recently witnessed for the first time near Jupiter’s north pole.
“When I first saw this, I thought I’d made a mistake,” Will Dunn, a PhD student studying astrophysics at the University College London, told Gizmodo. The northern lights Dunn observed on Jupiter are hundreds of times brighter than the aurora borealis on Earth. “We’re still not sure exactly what’s causing it.”
Jupiter’s northern lights, created when the gas giant’s prodigious magnetic field interacts with charged particles from the Sun, have long fascinated planetary scientists. But after decades of observation, many puzzles remain. Chief among Jupiter’s space weather mysteries is a bright x-ray aurora, located near the planet’s north pole. It never goes away, but since 2006, scientists have watched it brighten and fade every 45 minutes, light a lightbulb on a dimmer switch. Now, Dunn’s observations with the Chandra X-ray observatory and other telescopes have added another twist to this dazzling enigma.
Writing today in the Journal of Geophysical Research, Dunn and his co-authors describe what happened when a coronal mass ejection—a giant cloud of magnetized plasma that erupted from the surface of the Sun—struck the gas giant’s magnetosphere in 2011. When this happens on Earth, we get the northern lights. On Jupiter, the forever-aurora gets bigger and flashier.
“We saw the pulsing get much quicker: it happens about every 26 minutes during a solar storm,” Dunn said. “And we saw a bright enhancement in a region where we’d never seen it before.”
“If your eyes could see x-rays, you’d see something similar to the aurora on Earth,” Dunn continued. “Except the flashing across the the sky would be much bigger and brighter. Jupiter’s auroras cover a region larger than the entire Earth, so it would stretch as far as the eye can see.”
Why Jupiter’s northern lights flicker to a particular tempo, and why that flickering accelerated during the 2011 solar storm, are questions that planetary scientists would love to answer. “We think that when a coronal mass ejection crashes into Jupiter’s magnetosphere, it compresses it by about 2 million kilometers,” Dunn said. But for more details, we may have to wait for NASA’sJuno mission, which reaches the boundary between the Jupiter’s magnetic field and the solar wind this summer.
In addition to offering yet another mind-blowing glimpse into the meteorological events occurring in our cosmic backyard, Jupiter’s aurora provides a second benchmark for understanding how magnetic fields protect planets from powerful stellar eruptions. And that knowledge may eventually aid in the search for life beyond our solar system.
“We have a pretty good understanding of how the Earth’s magnetosphere works,” Dunn said. “But the universe is filled with magnetically active objects, including billions of exoplanets. Understanding the diversity of magnetic fields has relevance for understanding whether any of those other planets can support life.”
After five years and 445 million miles, NASA’s Juno mission arrives in orbit around Jupiter on Monday to begin an unprecedented scientific study of the behemoth planet that shaped our solar system.
In addition to doing amazing science, Juno itself is an amazing machine, built to fly risky maneuvers in an unimaginably hostile environment. Here are five things you should know about one of the most ambitious space exploration missions ever built.
It’s About to Break a Speed Record
Over the past few weeks, Jupiter’s gravity has been reeling Juno in, accelerating the spacecraft to breakneck speeds. By the time it arrives, Juno will be one of the fastest human-made objects in history, moving approximately 260,000 kilometers per hour (165,000 mph) relative to the Earth. That’s roughly ten times the top speed of the Space Shuttle.
When it enters Jupiter’s orbit on the evening of July 4th, Juno will shed some of its velocity in 35-minute main engine burn. But even after slowing down to a paltry 210,000 kilometers per hour (130,000 mph), it’ll still be the fastest spacecraft ever to enter orbit around a planet. The reason for Juno’s incredible speed? Getting the spacecraft as close to Jupiter’s cloud tops as possible.
It’s a Nuclear Fallout Shelter
It’s hard to imagine a more terrible place to operate sensitive electronics than Jupiter’s cosmic backyard. The gas giant’s magnetic field is constantly sucking up charged particles from the solar wind, ensconcing the planet in “radiation belts” millions of times more intense than anything experienced on Earth.
To shield Juno’s scientific payload, the spacecraft has been outfitted with a first-of-its kind radiation vault. A 180 kilogram (400 lb) titanium box roughly the size of an SUV trunk, the vault will reduce ambient radiation exposure approximately 800 fold. “The radiation vault is a very cost-effective technique, and I think it’ll feed forward into other missions,” Juno project manager Rick Nybakken told Gizmodo.
Outside of the vault, the scientific instruments’ external sensors are spot-shielded with tantalum, while Juno’s solar panels are coated in a special radiation coverglass. Even with all of this protection, the spacecraft will accrue radiation damage over time. By the end of its mission in February 2018, it’ll have been dosed with the equivalent of 100 million dental x-rays.
It’s Got Astronomically Bad Reception
Frustrated when your phone has shitty reception? NASA can put your problems in perspective. When Juno phones home to tell us that its orbital insertion maneuver went off smoothly, the signal it sends to Earth will be roughly a billion times weaker than what you’d receive in a typical cell phone call.
“Juno is trying to protect itself going into orbit, and it’ll be turned away from the Earth,” said Sonny Giroux, the Deep Space Network program manager at communications company Harris Corporation. “That means the signal during the orbital insertion event is much weaker than what we got back from New Horizons.”
Two stations in the Deep Space Network—one in Goldstone, California, another in Canberra, Australia—are going to be listening for Juno’s call; arraying several of their antennae to maximize detection power and focusing on Juno’s position in the sky with laser precision. “This is basically like hitting a hole in one from California to D.C.,” Giroux said, describing the accuracy and precision needed to catch Juno’s signal.
It Runs on Renewables
Juno is the furthest solar powered mission ever conceived, built to run on the sun in an environment 25 times dimmer than the Earth. Even with state-of-the-art solar technology and energy-efficient electronics, the spacecraft needs to catch a lot of sunlight. Spanning 20 meters (66 feet), its three solar arrays contain approximately 18,000 solar cells in all.
Juno’s orbits were designed so that it never flies behind Jupiter into darkness—except during its boldest maneuver, the orbital insertion. “For this one maneuver, we have to turn the spacecraft 90 degrees and go out of the sun for a period—but we’ve sized the batteries for that,” Nybakken said. Still, he added, “I’m not really going to relax until that main engine burn is complete.”
We Can All Help Juno Pick Targets
NASA learned a lot about public engagement from the New Horizons Pluto flyby last year, and with Juno, the space agency has hit its stride. To keep the Jupiter-loving public involved in the latest planetary science discoveries, it installed JunoCam. This citizen science camera allows amateur astronomers to decide which of Jupiter’s swirling storm clouds should be photographed during each of Juno’s 33 close flybys. With a field of view much wider than that of the Voyager probe, JunoCam will capture panoramic shots of Jupiter from altitudes as low as 3,100 miles above the cloud tops. Check out theJunoCam website to learn more.
Scientists at MIT have designed an ingenious new concept for a battery that operates on the same fundamental principal as an hourglass—it relies on gravity to generate energy. They described the device in a recent paper forEnergy and Environmental Science.
The fundamental concept of a battery is quite simple. There is a positive and negative terminal; electrons are produced by chemical reactions inside the battery, and collect on the negative terminal because they are negatively charged. Connect a wire between the two terminals, and the electrons will flow to the positive terminal. This wouldn’t be helpful all by itself, but the wire usually also connects a “load”—a light bulb, a motor, a radio circuit—and the energy is harnessed to power that device.
Liquid flow batteries were first developed back in the 1970s, so called because the materials used for the positive and negative electrodes are in liquid form, separated by a membrane. Any number of chemical compounds can be used, except instead of solid slabs, the battery uses tiny particles in a liquid slurry. But even liquid flow batteries typically require complicated systems involving storage tanks, pumps, and valves. That’s costly to maintain, since there are far more possibilities for leaks or failures.
So Yet-Ming Chang and his MIT colleagues came up with an alternative design concept for liquid flow batteries—one that simply relies upon gravity as a pump mechanism, substantially reducing the complexity of the entire system, and hence the overall cost.
The device looks more like a windowpane than a traditional hourglass, but the concept is the same: the slurry containing the particles flows from one end to the other via a narrow channel. You can change the rate at which energy is produced simply by shifting the angle of the device, much like tipping an hourglass or egg timer can slow or speed up the flow of grains of sand from one end to the other.
It’s just a proof-of-concept design at the moment, but Chang et al. are confident they can build a viable prototype. And when they do, it could prove to be game-changer for, say, scaling up wind and solar power systems, by providing larger grid-connected storage systems.
There’s been a lot of fascinating work in recent years to come up with ingenious ideas for new kinds of batteries. For instance, back in 2006, a team of MIT researchers led by Angela Belcher created new battery technology based on a genetically engineered M13 virus—small and flexible enough to power tiny sensors capable of detecting cancer or similar disease when implanted into the human body.
In fact, a few years ago designer Mike Thompson created a “blood lamp” that requires users to break off the top of the bulb-shaped glass, cut their finger on the jagged edge and then mix a tablet in with their own blood to create light:
That’s a stark reminder that all energy has an intrinsic cost.