Tag: earth

Gecko-Inspired Robot Has Grippers That Help Could Clean Up Space Debris

robot

In space, grabbing onto things is hard. A new robot that uses grippers inspired by gecko feet could solve that problem, helping clear up the mess of debris that orbits Earth.

The toaster-sized device can grip, hold onto and move around even large, smooth surfaces in microgravity, on both flat and curved objects.




To do this, it uses a “dry adhesive” material created by Hao Jiang at Stanford University in California and his colleagues.

In an environment where an accidental nudge can send something flying and space debris can be travelling faster than the speed of sound, agility is key.

Please like, share and tweet this article.

Pass it on: Popular Science

How Aliens We’ve Never Met Could Help Humanity Escape Self-Destruction

Humans have had such a dramatic impact on Earth that some scientists say we’ve kickstarted a new geological era known as the Anthropocene.

A fascinating new paper theorizes that alien civilizations could do the same thing, reshaping their homeworlds in predictable and potentially detectable ways.

The authors are proposing a new classification scheme that measures the degree to which planets been modified by intelligent hosts.

Whenever a distant exoplanet is discovered, astronomers categorize it according to its most obvious physical features and orbital characteristics.

Examples include hot-Jupiters, Earth-like terrestrial planets, and brown dwarfs.

With ongoing advances in telescope technology, the day is coming when astronomers will be able to expand on these simple characterizations, classifying a planet according to other features, including atmospheric or chemical composition.

But as a new study led by University of Rochester astrophysicist Adam Frank points out, we may eventually be able to place exoplanets within an astrobiological context, too.




In addition to taking the usual physical measures into account, Frank and his colleagues are proposing that astronomers take the influence of a hypothetical planet’s biosphere into account—including the impacts of an advanced extraterrestrial civilization.

Frank’s hypothetical planets, ranked from Class I through to Class V, range from dead, rocky worlds through to planets in which a host intelligence has solved the problems caused by its own existence, like excessive use of resources and climate change.

Moreover, as Frank explained, this paper presents more than just a planetary classification scheme—it’s a potential roadmap to an environmentally viable future.

If we discover signs of an advanced alien civilization—and that’s a big if—we may learn a thing or two about how we might be able to survive into the far future.

Indeed, we’re at a critical juncture in our history, one in which we’re crafting the planet according to our will—and so far, we’re not doing a very good job of it.

There’s ongoing debate as to whether or not our planet has crossed into the Anthropocene epoch, a new geologic chapter in which we’ve become the primary driver of planetary change.

Some scientists point to the fact that half of the planet’s land surface has been claimed for human use, or that Earth’s biogeochemical cycles of nitrogen and phosphorus have been radically altered on account of agriculture and fertilizer use, as evidence that we have.

While the technical debate over what constitutes evidence of a geologic shift continues, it’s clear humanity is altering Earth in some rather profound ways.

So much so, says Frank, that we need to place our planet, and the Anthropocene itself, within an astrobiological context. What’s happening here on Earth, says Frank, is likely happening elsewhere in the Galaxy.

Though we may be inclined to think that our situation is somehow special or unique, we have no good reason to believe that’s really the case.

Please like, share and tweet this article.

Pass it on: Popular Science

It Seems Someone Is Producing A Banned Ozone-Depleting Chemical Again

The Montreal Protocol—a 1987 international agreement to end production of ozone-destroying chemicals like freon—seems miraculous compared to the long struggle to achieve meaningful action on climate change.

Even more astonishing is that the agreement has worked. Those chemicals (known as CFCs) take a long time to flush out of the atmosphere, but monitoring has shown that the flushing is proceeding largely according to plan.

That keeps the hole in the ozone layer on track to shrink over the coming decades. However, a new study shows that someone has been cheating in the last few years.

A group of researchers led by Stephen Montzka of the US National Oceanic and Atmospheric Administration had been tracking the progress of CFCs and noticed something off with CFC-11.

This chemical has been used as a refrigerant, solvent, and propellant for aerosol spray cans, as well as in the production of styrofoam. As with the other CFCs, nations agreed to end production of CFC-11 entirely.

While there may still be some older machines leaking CFC-11, these sources should gradually disappear over time, allowing the decline of its atmospheric concentration to accelerate.




Hiding the decline?

Instead of an accelerating decline, CFC-11 showed a steady drop of 2.1 parts-per-trillion each year between 2002 and 2012.

Since then, its decline has actually slowed. Between 2015 and 2017, CFC-11 dropped at only 1.0 part-per-trillion per year.

There are a few possible explanations to sort through. The most important one is natural variations in the transport of emitted CFCs into the stratosphere, which depends on weather patterns.

But some of them can be eliminated quickly. A sudden uptick in the demolition of old buildings with CFC-11 refrigerants in their HVAC systems doesn’t seem to plausibly fit the data, for example.

Careful analysis of the data and some modeling can help us choose among the remaining explanations.

First off, the concentration of these gases has always been a little higher in the Northern Hemisphere than the Southern Hemisphere, because most of the sources are in the north.

Over the last few years, the difference between the two hemispheres has increased a bit. Similar gases haven’t done that, which points to increased emissions from the Northern Hemisphere rather than just a change in the winds.

Second, measurements from atop Mauna Loa in Hawaii show correlations between CFC-11 concentrations and a few other gases known to come from industrial emissions.

That means CFC-11 isn’t the only human pollutant seeing an uptick over the same time span.

A new source

At the height of use in the 1980s, humans released 350,000 tons of CFC-11 each year—a number that dropped to 54,000 tons per year in the early 2000s.

An additional 6,500 to 13,000 tons released each year in Eastern Asia would be enough to change the declining trend in just the way we’ve observed.

An increase that large seems to require renewed production of CFC-11—violating the Montreal Protocol.

Seeing as nations are required to track CFC production and report accurate numbers to the United Nations group that oversees the Montreal agreement, this is going to be a contentious conclusion.

The researchers chose their words carefully, and the network of measurements isn’t complete enough to point the finger at a specific nation.

Still, the list of suspects is short, and some nation needs to find and snuff out the illicit industrial activity within its borders in order to hold up its end of the Montreal Protocol.

Please like, share and tweet this article.

Pass it on: Popular Science

Ways To Prove The Earth Is Round

There’s a group of people who’ve lost trust in scientists, professors, academics, and pretty much anyone who is paid to establish and dispense facts.

Some of these people are rejecting a fact established hundreds of years ago that sits at the core of most modern biology, geology and astronomy: We live on a big, round, spinning ball.

 




Go to the harbor

When a ship sails off toward the horizon, it doesn’t just get smaller and smaller until it’s not visible anymore. Instead, the hull seems to sink below the horizon first, then the mast.

When ships return from sea, the sequence is reversed: First the mast, then the hull, seem to rise over the horizon.

The ship-and-horizon observation is so self-evident that 1881’s “Zetetic Astronomy,” the first modern flat-Earth text, devotes a chapter to “debunking” it.

The explanation relies on assuming that the sequential disappearance is simply an illusion brought on by perspective.

This debunking does not make much sense, however, as there’s nothing about perspective that should make the bottom of an object disappear before the top.

If you’d like to prove to yourself that perspective isn’t the reason for boats disappearing hull-first and returning mast-first, bring a telescope or binoculars on your trip to the harbor.

Even with vision enhancement, the ship will still dip below the curve of the Earth.

Look at the stars

Greek philosopher Aristotle figured out this one in 350 B.C., and nothing’s changed. Different constellations are visible from different latitudes.

Probably the two most striking examples are the Big Dipper and the Southern Cross. The Big Dipper, a set of seven stars that looks like a ladle, is always visible at latitudes of 41 degrees North or higher.

Below 25 degrees South, you can’t see it at all. And in northern Australia, just north of that latitude, the Big Dipper just barely squeaks above the horizon.

Watch an eclipse

Aristotle also bolstered his belief in a round Earth with the observation that during lunar eclipses, the Earth’s shadow on the face of the sun is curved.

Since this curved shape exists during all lunar eclipses, despite the fact that Earth is rotating, Aristotle correctly intuited from this curved shadow that the Earth is curvy all around — in other words, a sphere.

Go climb a tree

This is another one of those self-evident things: You can see farther if you go higher. If the Earth was flat, you’d be able to see the same distance no matter your elevation.

Think about it: Your eye can detect a bright object, like the Andromeda galaxy, from 2.6 million light-years away.

Seeing the lights of, say, Miami from New York City (a distance of a mere 1,094 miles or 1,760 kilometers) on a clear evening should be child’s play.

Please like, share and tweet this article.

Pass it on: Popular Science

What If The Moon Disappeared Tomorrow?

Ah, yes, the moon. To it, over it, shooting for it. Blue, green. Pies, faces, shines, lighting. And I haven’t even gotten to all the Luna-based concepts. Earth’s moon plays a significant role in our culture, language and thoughts.

But does it … you know … matter? If it disappeared in the blink of an eye tomorrow (and for discussion’s sake let’s assume it does so nonviolently), would we even notice? Would we even care?

Well, it depends ….

Do you like tides?

Gravity — at least the Newtonian kind — is pretty straightforward: The closer you are to something, the stronger its pull of gravity.

So stuff that’s closer to the moon gets a stronger gravitational tug, and stuff that’s farther away gets a weaker one. Easy-peasey.

When looking at the effects of the moon on the Earth, you can essentially boil it down to three parts: The Earth itself, the ocean-close-to-the-moon and the ocean-far-from-the-moon.

On any given day, the ocean closest to the moon gets a bonus gravitational pull, so it rises up slightly, reaching out in watery embrace to what it can never reach.




And since the ocean is so big, all the water from one horizon pushes up against water from the other, resulting in a fantastic tidal bulge.

OK, tide on one side of our planet, done. But what about the other?

The solid rocky bits of the Earth are closer to the moon than the ocean on the far side, so the Earth too gets a little more snuggly with the moon, leaving the far-side ocean behind.

Result? Tides on the far side. From the perspective of someone standing on Earth, it looks like that ocean is rising up, but really it just doesn’t get to join the party. And there you have it: two tides on opposite sides of the Earth.

If the moon disappeared, we wouldn’t be totally out of tidal luck; the sun also stretches and squeezes the Earth, so our surfing opportunities wouldn’t be completely eliminated.

Do you like 24 hours in a day?

The Earth used to spin on its axis faster than it does today. As in, way faster. After the hypothetical giant impact that led to the formation of the moon, the Earth’s day was as short as 6 hours. How did it get to a leisurely 24?

That’s right, it was the moon! The moon makes some pretty nice tides, but the Earth is also spinning on its axis. That spinning physically drags the tidal bulges around the planet.

So instead of the tides appearing directly beneath the moon, they’re slightly ahead of it, orbitally speaking.

So you’ve got a big lump of extra ocean water in a place where it’s not supposed to be. Since gravity is a two-way street, that lump pulls on the moon.

Like tugging a reluctant dog on a leash, that tidal bulge yanks on the moon bit by bit, accelerating it into ever-higher orbits.

By the way, the moon is slowly getting farther away from Earth.

And that energy to accelerate the moon has to come from somewhere, and that somewhere is the Earth itself: Day by day, millennium by millennium, the Earth slows down, converting its rotational energy into the moon’s orbital energy.

If you took away the moon, itꞌs not like this process would reverse, but it wouldn’t keep going. That might or might not be a good thing, depending on how much you like the length of your workday.

Do you like seasons?

The Earth’s axis is tilted, and that tilt can change with time. No biggie, all the planets do it; it’s fun. But what’snot fun is when the tilt changes rapidly.

What would happen if Antarctica pointed straight at the sun for 24 hours a day, plunging North America and Europe into permanent darkness?

And then a few hundred thousand years later it flipped over? We take the long-term regularity of our seasons for granted, and we might have the moon to thank for it.

Those kinds of crazy wild swings in the axial tilt are due to resonances, or unlucky interactions with distant objects in the solar system.

For instance, letꞌs say that one day in its orbit the Earth’s axis just happens to point away from the sun, and Jupiter is hanging out in that direction at the same time.

And let’s say that happens again … and again … and again. Every time Earth’s axis and Jupiter line up, it gets a super-tiny gravitational pull. At first it’s nothing.

But over millions of years it can add up. Before you know it, the accumulation of tugs has flipped the Earth over like a pancake.

What might stabilize this is the moon: it’s really, really big, and orbits us pretty fast. All that angular momentum prevents the other planets from playing any axial shenanigans.

Or not. The moon may actually be hurting us in the long term, since it’s slowing us down, which makes us more susceptible to the intrigues of the outer planets.

But that’s a billion-year problem anyway, and if the moon disappeared tomorrow, our seasons would still be seasonal for a really long time.

So, besides the tides, would we notice a disappeared moon? Well, yes, because it’s really big and bright, and there’d be nothing to howl at anymore. But would it affect us? Not really. So as for the moon … I’m over it!

Please like, share and tweet this article.

Pass it on: Popular Science

How Do We Clean Up All That Space Debris?

This is a big problem that many people are still trying to figure out, because there is a lot of junk out in space, and it is incredibly dangerous.

As of September 2012, we are currently monitoring 21,000 individual pieces of stuff orbiting the planet which are larger than about 2 inches.

Anything this size which is going fast enough to stay in orbit poses a significant threat to satellites, spacecraft, and space stations.

The ISS will regularly maneuver out of the way of space junk if we see it coming soon enough.

If there isn’t enough time to move the whole ISS, then the crew members of the ISS have to take shelter in one of the Soyuz capsules which are attached to the ISS in case an emergency evacuation is needed.

The two inch limit on tracking isn’t an indication that there aren’t any pieces smaller than that, or that we don’t have to worry about the little ones; we simply can’t spot them from the ground.




We fully expect there to be around 100 million more objects out there in the < 0.5 inch category.

Even paint chips at orbital speeds can cause significant damage to a spacecraft. A few of the space shuttle missions had paint flakes impact the windshield of the craft, which is an unsettling sight to say the least.

I can tell you the worst way to clean up a dead satellite, which unfortunately happened in 2007; the Chinese military decided to test their anti-satellite technology on one of their dead weather satellites.

This test successfully exploded the dead satellite, and created over two thousand new pieces of space debris, which, at the time, increased our space junk tally by 25%.

There have been a few suggestions on how to get the stuff that’s already up there down; some options are more passive than others.

The space station Mir ran an experiment in 1996 where they attached pieces of gel onto the outside of the space station to see what kinds of microscopic space junk they could catch.

They found a lot of liquid droplets, soap, and tiny paint fragments, along with pieces of broken spacecraft, and tiny electronic fragments.

This was instructive, but not particularly effective for cleaning out the reservoir of stuff surrounding our planet.

The best method to date to keep the skies clear is to make sure that when you put a spacecraft up in space, it comes with a way to come down again.

Usually this means that the craft should have a way to intentionally slow itself down enough to re-enter the atmosphere.

But those are only options for spacecraft which haven’t yet been launched, or have thought ahead more than most, and it doesn’t help get rid of the dead satellites we can’t communicate with, or any of the broken pieces of satellite shrapnel.

For those, the only option is to send up some kind of clean-up satellite which can help slow down all the miscellaneous pieces.

Again, there have been many proposals; the most plausible involve grabbing onto dead spacecraft somehow, and then de-orbiting as a pair.

Unfortunately, we can’t just go up and push every dead satellite down to Earth; not only is this impractical in the extreme.

All of the privately owned satellites are still privately owned regardless of whether or not they still work, and burning them up in the atmosphere would be burning someone else’s property, even if it doesn’t work anymore.

For now, until some of these cleaner satellites can get up there and start pulling down some of the pieces, our main goal with space debris is simply to not produce any more than we already have.

Please like, share and tweet this article.

Pass it on: New Scientist

Scientists Say Earth’s Magnetic Field Isn’t About To Flip, But It’s Definitely Doing Something Weird

Every few hundred thousand years, Earth’s magnetic field flips, and considering the huge impact that would have on everything from satellite systems to electrical grids, scientists are very keen to work out when the next one might be.

Hopefully it won’t be for a while yet, according to the latest study – by analysing recent near-reversals of the our planet’s magnetic field, researchers have concluded that we’re not in line for a reversal in the near future… at least based on what’s happened in the past.

The international team of experts compared the current state of Earth’s magnetic field with conditions during the Laschamp event (about 41,400 years ago) and the Mono Lake event (about 34,000 years ago).

On both those previous occasions the magnetic field recovered without a flip, and the scientists think the same will happen now.

There has been speculation that we are about to experience a magnetic polar reversal or excursion,” says one of the team, Richard Holme from the University of Liverpool in the UK.




However, by studying the two most recent excursion events, we show that neither bear resemblance to current changes in the geomagnetic field and therefore it is probably unlikely that such an event is about to happen.

Our research suggests instead that the current weakened field will recover without such an extreme event, and therefore is unlikely to reverse.

Both the Laschamp and Mono Lake events were smaller shifts that didn’t result in complete flips, as we can tell from magnetised volcanic rocks, particularly those embedded under the ocean floor.

The research matches our current magnetic field scenario with two other points at 49,000 years and 46,000 years in the past, prior to the previous events.

If a complete flip didn’t happen on those occasions, the hypothesis goes, then a flip isn’t about to happen now either.

There are in fact two outcomes to look out for: a geomagnetic reversal, where magnetic north and magnetic south change places, and a geomagnetic excursion, where there are short-lived changes in the field intensity rather than the field orientation.

Both reversals and excursions can weaken Earth’s magnetic field, allowing more solar radiation to hit the surface.

While this wouldn’t be damaging enough to affect us (human beings have survived through past events), it could cause serious problems with satellite, communications, and power systems.

There’s also the possibility it might interfere with the planet’s temperature and climate, but scientists just aren’t sure at the moment what the effects will be – the last full flip was 780,000 years ago, after all.

The general consensus is that these changes in Earth’s magnetic field are caused by movements of molten iron and nickel deep in the planet’s core.

In fact, smaller fluctuations in field strength and magnetic poles are happening on a regular basis, so scientists are keen to collect as much data as possible on them.

In particular, experts are keeping an eye on the South Atlantic Anomaly (SAA), currently the weakest part of Earth’s magnetic field. It’s slowly weakening and slowly moving westward at the same time.

The more data we have, the more accurately we can predict when a reversal is likely to happen – and make sure we’re ready for it.

Please like, share and tweet this article.

Pass it on: Popular Science

NASA Releases Astounding Video Of The Lagoon Nebula To Celebrate Hubble’s Birthday

The Lagoon Nebula as seen by Hubble in 1996.

Ever wanted to zoom near that central bulge in the Milky Way in the Sagittarius constellation where stars are born? NASA has almost made it possible thanks to the Earth-orbiting Hubble Space Telescope.

As a kind of a 28th Hubble birthday gift for all of us, the space agency has posted astounding videos and photos of what’s known as the Lagoon Nebula.

The main video takes viewers from far away into the very heart of the massive, colorful nebula, what NASA calls a “raucous star nursery full of birth and destruction,” 4,000 light-years away from Earth.




At the Lagoon Nebula’s heart is a massive “young” star (the million-year-old Hershel 36), 200,000 times brighter and eight times hotter than Earth’s sun.

It roils the region with ultraviolet radiation and winds carving out an exploding, undulating “fantasy landscape of ridges, cavities, and mountains of gas and dust,” gushes NASA.

Hubble was launched April 24, 1990, aboard the space shuttle Discovery and was a joint project of NASA and the European Space Agency.

The lagoon nebula seen in visible light ( left) and infrared (right).

Once a year the telescope takes a break from its assigned observations to take a detailed image of a particular spot of the cosmos.

The Hubble “has offered a new view of the universe and has reached and surpassed all expectations for a remarkable 28 years,” said NASA and the ESA. The telescope has “revolutionized almost every area of observational astronomy.”

Please like, share and tweet this article.

Pass it on: Popular Science

So You Want to Be A Space Tourist? Here’s What You Can Do

Though we’ve been living in the Space Age for more than half a century, going into space remains an extreme rarity.

Fewer than 600 people have gone above the Kármán line — the point, about 62 miles above Earth, that marks the beginning of space — and all were put there by the U.S. or another nation’s government.

But the rise of private spaceflight companies like Virgin Galactic and Space X means that the final frontier may soon be within reach of a great many more of us.

The firms have announced plans to put private astronauts, a.k.a. space tourists, on orbital or suborbital flights within the next few years.




Initially, the cost of a ride on one of these rockets will be hundreds of thousands of dollars at a minimum. That puts the experience within reach of only the wealthiest people.

But advances in rocket and capsule design are expected to lower the price to the point that people of more modest fortunes are able to afford a ticket.

Some projections put the global space tourism market at more than $34 billion by 2021.

What Space Tourists Can Expect

What exactly is in store for space tourists? The excitement of a rocket ride and a chance to experience weightlessness, for starters.

And the bragging rights are hard to beat. But some say the biggest benefit of going into space is getting a dramatic new outlook on life on the fragile blue marble we call home.

It’s a perspective shift that could have profound implications not just for individuals but also for society at large.

Billionaire computer engineer Charles Simonyi flew to the International Space Station aboard a Russian spacecraft with the assistance of a Vienna, Virginia-based firm called Space Adventures, and he echoes that sentiment.

It’s great to go to space just because it’s there,” he says. “But I think space is our destiny and we will discover great benefits from it.

Flying High

Virgin Galactic plans to offer suborbital jaunts into space, with customers being treated to six minutes of weightlessness along with that one-of-a-kind view.

The Las Cruces, New Mexico-based company says more than 600 customers have signed up, including Leonardo DiCaprio, Katy Perry, Ashton Kutcher, and the late physicist, Stephen Hawking.

The price of a ticket stands at $250,000, with registration open for anyone who has that kind of extra cash on hand.

Virgin CEO Richard Branson said on July 5 that he hopes to see space tourists flying on Virgin by the end of 2018. But other executives at the firm seem reluctant to commit to that.

Please like, share and tweet this article.

Pass it on: Popular Science

The Recovery Of Our Ozone Layer Could Be Delayed For 30 Years!

The restoration of the globe’s protective shield of ozone will be delayed by decades if fast-rising emissions of a chemical used in paint stripper are not curbed, new research has revealed.

Atmospheric levels of the chemical have doubled in the last decade and its use is not restricted by the Montreal protocol that successfully outlawed the CFCs mainly responsible for the ozone hole.

The ozone-destroying chemical is called dichloromethane and is also used as an industrial solvent, an aerosol spray propellant and a blowing agent for polyurethane foams.




Little is known about where it is leaking from or why emissions have risen so rapidly. The loss of ozone was discovered in the 1980s and is greatest over Antarctica.

But Ryan Hossaini, at Lancaster University in the UK and who led the new work, said: “It is important to remember that ozone depletion is a global phenomenon, and that while the peak depletion occurred over a decade ago, it is a persistent environmental problem and the track to recovery is expected to be a long and bumpy one.”

“Ozone shields us from harmful levels of UV radiation that would otherwise be detrimental to human, animal and plant health,” he said.

chemicals

The chemical was not included in the 1987 Montreal protocol because it breaks down relatively quickly in the atmosphere, usually within six months, and had not therefore been expected to build up. In contrast, CFCs persist for decades or even centuries.

But the short lifespan of dichloromethane does mean that action to cut its emissions would have rapid benefits. “If policies were put in place to limit its production, then this gas could be flushed out of the atmosphere relatively quickly,” said Hossaini.

Please like, share and tweet this article.

Pass it on: New Scientist