5 Unsolved Mysteries About Our Solar System

In the grand scheme of things, we have not been at the space exploration game very long, but we have already learned a ton about the solar system. We have sent probes to planets and asteroids and comets. We know what they look like, what they are made of, their temperatures, atmospheres and so much more.

But you know what is even more amazing? What we don’t know. The truth is, there's still a lot we don't understand about our little corner of the universe. So let's look at just a few unsolved mysteries of the solar system.

1: What Causes The Sun's Magnetism?

The Sun's magnetic field. Magnetic fields everywhere are created by the movement of charged particles. On Earth, for example, a flow of charged particles deep inside the outer core of our planet generates the magnetic field that makes your compass point north and protects us from dangerous solar radiation.

Now, we know that the Sun has a magnetic field too. Maybe that is not surprising. After all, the Sun's made of plasma, a kind of gas in which electrons and ions have separated and are free to move around, a recipe for a magnetic field. But we still don't know exactly how it works or where it forms.

Does it start near the solar surface or deep inside the Sun? How do the different layers affect each other? Getting to the bottom of this matter, because it will help us understand everything from solar flares, to the northern lights to radiation that astronauts will have to deal with while on there way to Mars. Plus, it could help us predict what the magnetic fields of other stars might be like.

But above all, unlocking the secrets of the Sun’s magnetism will help us figure out why our star is so inconsistent. The Sun follows an 11-year cycle. At the peak of this cycle, the Sun is brighter and there are more solar flares and sunspots. We call this peak the solar maximum.

But what's interesting is the way the Sun's magnetic field changes during the cycle. The lines of its magnetic field get more and more messy as it nears the solar maximum and then a series of explosions, known as coronal mass ejections, smooth it out again. The best we can tell, the field lines start out running straight from pole to pole, like they do on Earth. But then, because of the Sun spinning, they get wrapped around it like cotton candy. Eventually, these stretched and pulled field lines “snap” like a rubber band stretched too far, producing explosions and calming the field back down to where it started.

But all of this is based on what we can observe on the surface of the Sun. What we can’t figure out is how these phenomena are created by what’s happening beneath the surface. Maybe they are caused by forces between the outer layers of the Sun that are churning in convection currents, like pots of hot water and the parts below them that aren’t. Maybe it’s more about the motion in the convection currents themselves.

We still have a long way to go before we will understand where exactly the field originates. To get our answers, we will need to look much deeper.

2: Why Is Venus So Different From Earth?

Now a little further out from the Sun: the stormy planet Venus. Venus has always been a bit puzzling. It has been described as Earth's twin. It is roughly similar in size and it is well inside the Sun's so-called habitable zone, where liquid water could be a thing. But it turns out not so much.

In many ways, Venus is more like our evil twin. It is a planet of unrelenting storms, raging at 300kilometress an hour, and a runaway greenhouse effect that's given it an average temperature of 462 degrees Celsius. That is hot enough to melt lead. So, why is it so different from Earth? And what got that greenhouse effect started?

Well, we know what is causing the greenhouse effect today. The atmosphere is 95% carbon dioxide. That is a powerful greenhouse gas, the same gas that is the main cause of climate change on Earth. When you consider that Earth’s atmosphere only has 0.04% CO2, you can see why 95% might be a problem. The question is, why does Venus have so much?

Scientists think Venus was once a lot like the Earth with liquid water and not so much CO2. But at some point, it got warm enough that the water evaporated and since water vapour is a powerful greenhouse gas, too, this just made the heating worse. Eventually, it got hot enough that carbon that had been trapped in rocks was released, which ended up filling the atmosphere with CO2.

The million dollar question is: What got the heating started in the first place? Was it because the planet had a little too much CO2 to start with? Was it maybe a tad too close to the Sun? Or could it have been because of some catastrophic event? It's anybody's guess.

Despite all the questions we have about Venus, we have only sent three missions there, so we have a lot more exploring to do. In future missions, we could study its atmosphere, to better understand the weather patterns and figure out what chemical reactions happen in each layer. We could look for hotspots to see if there have been active volcanoes recently. We could even search for signs of past life, and study the planet's geology.

3: The Storms of Uranus

Now for another stormy place, this time on the outer reaches of the solar system: Uranus. When you get caught in a thunderstorm, it might be sticky and uncomfortable. But that is nothing compared to some of the storms in the rest of our solar system. And for the longest time, Uranus wasn't seen as particularly crazy in the storm department. That is, until 2014, when astronomers got a surprise.

Astronomers found clusters of gigantic methane storms sweeping across the planet. Before that, storms on other planets were thought to be driven by energy from the Sun. But the Sun’s energy just isn’t strong enough on a planet as distant as Uranus. And as far as we know, there isn't any other source of energy to drive such huge storms.

The only thing that scientists are pretty confident about is that the storms on Uranus start in its lower atmosphere, unlike Sun-driven storms, which occur higher up. Beyond that, though, the actual cause remains a mystery. Maybe we are totally wrong about what's going on in the middle of Uranus. The atmosphere could be much more dynamic than it seems from the outside, generating heat that is powering these storms. And it could be a lot hotter in there than we think, too.

It is possible that there is an atmospheric layer trapping heat inside the planet, making the upper atmosphere cooler and masking its true inner temperature. The secret may lie in how the different parts of the atmosphere interact. We just can't say for now. At the very least, these storms have taught us that there's a lot more to Uranus than meets the eye.

4: Why Does The Kuiper Belt End Suddenly?

Now we head out beyond the planets we know and love, to the Kuiper belt. The Kuiper belt is a disk of frozen bits of water, methane, and ammonia. It starts at the orbit of Neptune, 30 astronomical units from the Sun, and keeps going to about 50 AU from the Sun. But there's one thing about the Kuiper belt that's a huge mystery. Once we get to 50 AU, the belt just stops. It ends all of a sudden, something the astronomers call the “Kuiper cliff”.

This is not easy to explain, but we have a few ideas. It could be that the belt really does continue, but the objects become so small that we can't see them. But this idea doesn't fit with what we know about how the solar system formed. If anything, because of the complex interactions of the outer planets’ orbits, we do actually expect objects to start getting larger again at that distance.

A more exciting idea is that the objects may have been pulled away by the gravitational attraction of an as-yet-undiscovered planet. Such a planet, which would be the ninth planet in the solar system could be the size of Earth or Mars. Sadly though, it is tough to see anything that far out, so we might be waiting a while for the answer.

5: Is the Oort Cloud a thing?

So, the Kuiper belt is pretty far away, but there is one part of the solar system that is even more out there: the Oort Cloud. We all have a picture in our minds of the solar system as a flat disk. But astronomers have hypothesized for a long time that the disk might have a spherical shell around it. This shell, the Oort Cloud, is thought to be made up of icy rocks, water, methane, ethane, carbon monoxide, hydrogen cyanide, and other nasty stuff extending out as far as 2 light-years from the Sun.

Why do we think it is a thing? Well, every so often, we spot long-period comets, comets whose orbits take longer than 200 years, and when we trace back their paths, they seem to come from sources a long way out in every direction. Our mathematical models for how the solar system forms tell us the cloud should be out there, too.

As the mess of the early solar system collapsed into the disk we know today, we should expect small icy objects to be thrown into an outer shell by the gravity of Jupiter and the other gas giants. But even if it makes sense for it to be there, we have never actually observed the Oort Cloud.

Being so far away, with so little light, we just don't have the technology to see it. That means for the moment we have no way of proving that it exists or if it does, how big it is.

As these mysteries show, we don't have to go far to find puzzles, plenty of them, right on our own celestial doorstep And really, these five mysteries are only the beginning.

Also Read:- 3 Biggest Experiments Ever

Read More

3 Biggest Experiments Ever

There are things in nature so huge or complex that the only way to really study them is to build something enormous. Like, physicists didn’t just find the Higgs boson by fishing it out from under the couch. It took the world’s largest machine, the Large Hadron Collider, to observe it. But when it comes to outright size, there are a few scientific experiments that can even give the Large Hadron Collider a run for its money.

Take the Northeast Pacific Time-series Undersea Networked Experiments or NEPTUNE, for example, which is a really big name for a really big network of scientific equipment off the coast of British Columbia. You may have noticed that the ocean is gigantic. I mean, seriously. About 71% of the Earth’s surface is covered in water and despite all the seafaring we have done as a species, there’s still a ton we don’t know about what’ is going on deep under the surface.

NEPTUNE: It’s made up of an 800-kilometre loop of fibre optic cable that ranges from just 23 meters deep to 2.4 kilometres below the surface. The cable serves as a link between five locations that have all kinds of different equipment for studying the ocean and allows them to transmit data back to land. This equipment includes things like hydrophones, which are special underwater microphones used to listen to the sounds of life down there from swarms of plankton to whales. There is also an adorable robot called Wally and scientists use Wally to study microbes that survive on deposits of methane, on the ocean floor. And, there are cameras that provide livestreams of undersea activity, like mass crab migrations. You can watch that here:- http://www.oceannetworks.ca/sights-sounds/live-video.

Since it started operating in 2009, NEPTUNE has given us tons of data about ecosystems that adapted to the extreme pressure and lack of sunlight on the seafloor. And because it covers almost the entirety of one of Earth’s tectonic plates, scientists can use it to help build a more accurate model for things like earthquakes.

Further south, in Livermore, California, is one of the world’s biggest and heaviest indoor experiments. It is called the National Ignition Facility or NIF and its goal is to show that nuclear fusion, where two smaller atoms combine into a larger one, could be a viable source of power.

Existing nuclear power plants work using nuclear fission: they split atoms apart and turn the resulting energy into electricity. Unfortunately, in the process, they also produce waste that stays dangerously radioactive for decades. But fusing certain atoms together also releases energy and unlike splitting atoms, the process could potentially produce much less radioactive waste. Problem is, pumping enough energy into atoms to get them to fuse is challenging.

So, the NIF’s strategy is to use the largest laser in the world, which is housed in a ten-story building more than 300 meters long. Most of that space is for the laser amplifiers 120 metric tons’ worth of a special type of glass. Under the right conditions, it is capable of giving a series of 192 normal laser pulses 10 billion times more energy than they started out with. And then, all that laser energy gets fired into a gold canister about the size of a pencil eraser, which contains a target pellet filled with hydrogen. The beams heat up the pellet inside to over 3 million degrees Celsius, which is hot enough to make it implode in just the right way for the hydrogen atoms to start fusing with each other.

The chain reaction releases energetic, radioactive particles like neutrons, ideally with more energy than what the laser beams put into kickstarting the reaction in the first place. That’s what physicists call ignition. There is just one small problem. The NIF hasn’t achieved full ignition yet at least, not the kind that gets us more energy than we put in. And even if the NIF does achieve ignition, there are still a whole load of problems to tackle, like how to extract that energy efficiently and deal with all your expensive equipment being irradiated by the same particles you want to get energy from. But researchers are working on it, and eventually, that giant building full of glass could lead to power plants that use nuclear fusion.

So, NEPTUNE and the NIF are plenty big in their own ways. But neither of them qualify as the biggest experiment humanity’s working on. That award goes to the Laser Interferometer Space Antenna or LISA. Its a proposal to use three small spacecraft arranged about 1.6 million kilometres away from each other in space four times the distance from the Earth to the Moon! The spacecraft would shoot laser beams back and forth to measure gravitational waves, ripples in the fabric of space-time generated when massive objects like black holes accelerate when they are merging. 

In 2016, researchers detected gravitational waves for the first time using LIGO, a similar, but much smaller experiment set up here on Earth. The waves came from two relatively small black holes suddenly merging the whole thing took less than a second. And detecting them involved measuring a change in distance of only one ten thousandths the width of a proton.

So there is a reason it took us so long. LISA’s designed to detect gravitational waves that are even more subtle — ones that come from events that can last for minutes or even hours, like when the much-more-massive black holes in the centres of galaxies merge.

LISA probably won’t make it off the ground until about 2034. But in 2017 NASA completed a mission with a sort of mini version of LISA, called LISA Pathfinder, that showed the technology can function well enough to make measurements in space.

So while it won’t technically be on Earth, when it eventually launches LISA will be the biggest observatory we have ever built by far. And at 1.6 million kilometres across, that is going to be a tough record to break.

Source: Ocean Networks Canada, Lawrence Livermore National Laboratory, NASA

Also Read:- Why Does Time Pass?

Read More

Why Does Time Pass?

Why does time pass? It is a question so profound that few people would even think to ask it yet its effects are all around. Human beings live in a perpetual present inexorably sealed off from the past, but moving relentlessly into the future. For most people time seems to be something that is just out there, a thing ticking away in the background fixed immutable. Time seems to go in one direction in one direction only, but physicists see it much differently.

John Archibald Wheeler once said time is what stops everything from happening at once. In an interview, Andrew Jaffe, professor of Astronomy and Cosmology at Imperial College London, said that "I wish I could explain what it would be like for there not to be time, but I can't. We experience time, We are psychological creatures that have time and that's kind of one of our defining characteristics. So if time weren't around, we don't really have even a good way to describe what happens because happens, right? That's a verb right there that has to do with time. So I think once you start wondering about this you get much further into the realms of philosophy than physics."

But Dr Sean Carroll, Physicist at California Institute of Technology, stated that "I actually don't think it's that mysterious. We live in a world that is full of stuff and this world happens over and over again with the stuff in slightly different positions. Time is just the label on all those different moments that constitute the history of the universe. It is very much like the page numbers in a book."

One of the great minds who changed the way science thinks about time was Albert Einstein. In 1905 he published his special theory of relativity, which described the motion of objects moving near the speed of light? In it, he demonstrated that time passes differently in different places depending on how those places are moving with respect to one another.

So first, Einstein studied the effect of fast motion and he found that space and time got mixed up if you moved more quickly and that's his special theory of relativity. It is called the theory of relativity because even the difference between time and space is relative to what observer is doing the measuring, in particular, to how fast you are moving. This is something that we never notice in our everyday lives, but once you start moving close to the speed of light relativity becomes crucial.

Einstein showed that the faster one travels the slower time goes for the traveller. At the speeds at which humans move this is imperceptible. But for someone travelling on a spaceship at speeds close to that of light time would slow down compared with its passage for people on earth.

In an interview, Dr Kip S. Thorne, a theoretical physicist, once said that "one of Einstein's great insights was to understand that different people moving at different speeds through the universe, see different events as being simultaneous." There was another important aspect of Einstein's theory which he didn't even realize when he published it the Time, which was woven into the very fabric of space itself.

It was actually not Einstein but another German mathematician named Hermann Minkowski, who pointed out that Einstein's theory could be thought of as a theory of a single four-dimensional space-time. Einstein when first heard this idea said well, that's just a mathematician talking, that is not really something that is very useful to physicists. But once he tried to fit gravity into his theory of relativity, he realized the space-time concept was crucial.

Einstein used this insight to help develop his general theory of relativity, which incorporated gravity. He published it in 1915 ten years after his special theory of relativity which was focused solely on the motion. Dr Sean said that "Einstein tried very hard he worked for ten years after inventing special relativity to fit gravity into the framework and eventually he realized he needed a new framework. So he invented what we call the general theory of relativity, where Einstein says that this space-time stuff this four-dimensional world in which we live has a life of its own. Space-time itself can move it has dynamics it has curvature and it's that curvature that geometry of space-time that you and I experienced as the force of gravity. And then he found the time was also changed by your proximity to a very massive object like a Black Hole, but also just how close we are to the earth or to the Sun or anything else that has a gravitational field changes the passage of time"

With the general theory of relativity, he demonstrated that massive objects warped the fabric of space-time. It is this curvature that causes time to slow down near them. According to general relativity, time slows down near massive bodies. It slows down any place that gravity pulls you toward. Time slows down in proportion to the gravitational pull of a nearby object, so the effect would be strong near a black hole but milder near the earth. But even here it can be detected. Einstein's theories had to be taken into account when the GPS system was set up, otherwise, it would have been inaccurate.

These ideas about space and time being relative sound very wild and far out and removed for everyday experience. But to physicist they are very very important there's something we observe every day. One of the interesting things about Einstein's equations is that none of them suggests time goes in only one direction. They work equally well if time goes forwards or backwards. This is in contrast to everyday experience.

"One of the conundrums is that the laws of physics, for the most part, do not distinguish between time going forward and time going backwards and yet the actual world that we experience certainly is different forward to backwards.", said Andrew Jaffe. One scientist who puzzled over the directionality of time was Arthur Eddington, a 20th-century astronomer who defined the concept of the arrow of time-based on observations made by the 19th-century physicist Ludwig Boltzmann.

In space, there's no preferred direction. There's no difference in the laws of physics if you look left or look right. But there seems to be an enormous difference between the past and the future, that's what we call the arrow of time. And it's a little bit mysterious, Why is the past so different from the future? We think it's not a difference in the deep down fundamental laws of physics, It's actually just a difference because of the universe in which we live.

The arrow of time is just time as we experience one second following one other second following another second. It's just the psychological experience of time and the fact that things change as we experience them. But it seemed to happen in the world forward so buildings get built, but they decay slowly and it's that decay, there's at least partially responsible for the arrow of time. It's the increase of entropy.

The arrow of time is based on the second law of thermodynamics, which says the disorder known as entropy increases with time. For example, a building left untouched will slowly decay into its surroundings, it will disintegrate into a more chaotic state. But it is highly unlikely that the building will become more orderly over time. This is because there are many more ways for a system to be disorderly than orderly. There can be many ways for something to break for instance, but only one way for it to be put back together again. A system will be less disordered in the past and more disordered in the future. This is the arrow of time.

So how can the arrow of time be reconciled with Einstein's equations if time can go forwards and backwards according to relativity, Does that mean it's possible to go backwards in time?

Answer to the question is we actually don't know whether it's possible to travel backwards in time. But we do know it's possible to travel forwards. You can't help but travel forward in time, our best guess is that you just can't travel backwards in time.

The theory of relativity does allow time travel to the future if I go down near a black hole and stay there for one hour you may go forward by seven years by the time I come back. So you have moved forward in time seven years while I move forward in time just one hour.

Einstein's theories do allow for the formation of wormholes in space these are shortcuts that link otherwise distant places in the space-time continuum. So a wormhole is a hole in space and time that comes out somewhere else and it does it much faster than the speed of light potentially so it would be a way of violating what we think of otherwise as a fundamental speed limit in Einstein's theories. It does it in a way that doesn't obviously violate Einstein's theories, but we are not sure that there's any actual way you can build a wormhole.

Although wormholes are theoretically possible, they're a highly implausible proposition. That's because the equations suggest enormous masses and energies would be required to create and manipulate one. There are two problems of the wormholes one is if you don't have one how you create it? and the other is if you do have one, how do you hold it open? So, it doesn't collapse and prevents you from going through. In both cases what we understand about these questions is it points toward a conclusion that wormholes are probably forbidden by the laws of nature.

What remains then is a mystery? Theories fail to forbid travelling backwards in time, but practice suggests it might just as well be forbidden. For now, it would appear the arrow of time cannot be reversed. No, one knows. Why time passes, but it seems that no matter how people look at it, it goes in one direction in one direction only.

Also Read:- 7 Unresolved Mysteries About Our Ocean

Read More

7 Unresolved Mysteries About Our Ocean

Humans have done a pretty good job of exploring the Earth thus far, climbing mountains and crossing continents and planting our flags all over the place in the name of science. But one part of the world that has remained pretty mysterious to us also happens to cover more than 70% of its surface: the ocean.

Yes, we have sailed across it plenty of times and drilled for oil in it. And managed to create reality shows about fishing in it. But, from glowing oceans to massive deep-sea creatures and underwater ecosystems with thousands of undiscovered, basically-alien, species.

We still have a lot to learn about it. Probably more than any place on Earth, the ocean is full of fascinating stuff that we just don’t know. Not yet.

Number One: What’s The Ocean Floor Like?

Fact is, we still don’t know exactly what the ocean floor looks like in most places. The National Oceanic and Atmospheric Administration say that 95% of the ocean's bottom remains unseen by humans. As a result, we have a way better picture of the surfaces of other planets than we do of most of the seafloor.

In 2014, a team of scientists created a map of the seafloor using data from satellites equipped with special sensors called radar altimeters. These instruments could precisely measure the distance from the satellite to the surface of the ocean below. Essentially, any large mountains or canyons on the ocean floor have a slight gravitational effect on the ocean surface, creating bumps and dips, respectively.

These variations are of course too subtle to be detected by human eyes. But they can be measured by these ultra-precise satellite altimeters and after adjusting for the effect of waves and tides, tell scientists what’s on the seafloor. This map spans the entire ocean floor, which is awesome and we are all glad that it exists, but it only has a resolution of about 5 kilometres, which is pretty low. By comparison, most of the surface of Mars, Venus, and the Moon have been mapped to resolutions of 100 meters or less. So, if we want to know what’s going on down there and really explore the ocean, detecting life, specific mineral formations or wrecks, we are gonna need a better map.

Number Two: What’s Under The Seafloor?

OK, probably thinking that you know what’s down there: rock. Yes. But not just rock. In 2015, scientists reported that they had drilled down about 2 and a half kilometres below the seafloor off the coast of Japan, and discovered living microbes. There were only about 10 to 10,000 microorganisms in a cubic centimetre of sediment that they studied, compared to like billions that you’d find in the same amount of dirt from your garden.

But still: There's life down there, even in the intense heat and pressure many kilometres below where the ocean stops. And the genomes of these under-sea microbes showed that they were actually more similar to the kind you’d find in forest soil, rather than the ones in seafloor sediments.

So it’s possible that these microbes are descendants of terrestrial ones from 20 million years ago, that just adapted when their habitat began to get buried way beneath the ocean. So, who knows what other kinds of life could exist in deep marine sediments or what they could tell us about what life on Earth used to be like

Number Three: Brine Pools

We have all seen lakes and rivers on land, but what about lakes that are underwater? Sounds a little bit unreal, like maybe it’s from a Sci-fi movie but these features actually exist. Pockets of seawater that have a different composition than the surrounding ocean: because they are super salty. They are known as brine pools.

They seem to have formed when layers of salt from evaporated oceans millions of years ago got buried under layers of sediment. Seawater can reach these deposits and mix with the salt, forming a dense brine that flows out of the seafloor, sometimes filled with oils or methane gas.

Some brine pools, like those found deep in the Gulf of Mexico, are four times as salty as the ocean water around it. The brine is so dense that submersibles can even “float” on top of it, like a boat on a lake. All of this salt makes brine pools lethal to larger animals. But colonies of halophilic or salt-loving microorganisms can flourish there, usually in much higher concentrations than the nearby normal seawater.

Some pools are even lined with mussels that have symbiotic bacteria in their gills, which use the methane in the brine to make energy for the mussels. But there’s a ton that we don’t know about these weird underwater salt lakes like how brine pools can be so different from each other and why some have mussels and others don’t and even how many there are?

Number Four: Milky Seas

Milky Sea also known as mareel, this is a phenomenon in which thousands of square kilometres of the ocean’s surface glow a brilliant whitish-blue. It lasts for such a short time, and there have been so few recorded sightings, that these glowing seas were thought to be a myth made up by crazy sailors. Until 2005 when a group of researchers was studying satellite pictures of a swath of the Indian Ocean from 1995.

These pictures showed an area of about 15,000 kilometres-square, around the size of Connecticut, glowing for 3 nights. It was the first scientific evidence of the phenomenon, but the glowing waters are still not very well understood. Some have suggested that the glow is caused by a mass of tiny dinoflagellates called Noctiluca scintillans also known as “sea sparkles” for the way they glow when disturbed. These protists are what cause the picturesque glittering waves along coastlines in some parts of the world. But the 2005 study found that it was “unlikely, if not impossible” that the short-lived glowing of dinoflagellates was what scientists had been seeing from space.

The prevailing theory these days is that milky seas are caused by massive colonies of bioluminescent bacteria that are growing on top of an algal bloom. But we are still not sure how or why these ephemeral masses of bacteria gather, glow and disappear.

Number Five: The 52-hertz Whale

You would think we would know a lot about whales. I mean, they are big, we have their skeletons and we can observe their migratory patterns. But one thing we still have a lot more to learn about is their songs from why some whales make them, to how an animal without vocal cords or lips manages to make song-like sounds.

Then there is this question what whale is producing the 52 hertz sound and why? This whale song was first noted by a technician on December 7th, 1992 in the Northeast Pacific Ocean. It sounded like a blue whale, but blue whale cries usually are somewhere between 15 and 20 hertz in pitch.

But this whale cries at 52 hertz in pitch. This high-pitch noise seemed to be unique to one animal a whale that became known as 52 Blue. This raises a lot of questions and we have to know more about whales to be able to answer some of them, like, why does this one whale sound different? And can others even hear it? And if they can hear it, do they understand?

Some people latched onto to the idea that 52 Blue is a lonely whale crying out to others that might not hear it or wouldn’t call back. But several scientists have rejected this lonely narrative and think that other whales may be able to understand its call, even if they can’t make that call themselves. Also, 52 blue seems to migrate independently from any other whales. But its migratory patterns do look kind of like those of blue whales. 

Scientists have been tracking it up and down the North Pacific from Alaska to Mexico for years now. So some researchers think it might have some malformation that has changed how it sings or maybe it’s even a hybrid between a blue whale and another species. Whether or not it’s a lonely whale, 52 Blue is an oddity that people seem to love.

Number Six: Upsweep

Now, ocean sounds are practically their own field of study, NOAA has been monitoring acoustics in the ocean for decades now. Instead of microphones, which are used to collect sound in air, NOAA uses hydrophones to record underwater sounds. Mostly, these hydrophones are used to listen to the ambient sound of the ocean, to see how humans might interfere with it, and to listen for things like earthquakes and whale calls. And sometimes, they record things that are hard to explain, at least for a while.

In 1997, for example, there was what was known as The Bloop, an extremely loud, low-frequency sound heard by hydrophones some 5,000 kilometres apart. Oceanographers recently determined that it was the result of an icequake. Icequake: the cracking and collapse of glaciers into the ocean, in this case on the coast of Antarctica.

But there’s another mystery sound from the ocean, known as Upsweep. Recorded in August 1991, it sounds like a repeating “boop” that picks up at the end sweeping up kind of like the “red alert” sound effect you hear on spaceships in sci-fi movies.

Since 1991, this sound has been heard regularly in the Pacific Ocean, and it seems to be seasonal, usually becoming more common in spring and fall. Researchers have tracked the sound to a part of the Pacific that has lots of volcanic and seismic activity, which seem to be important clues. But according to NOAA, “the origin of the sound is unresolved.”

Number Seven: Why Are Deep-Sea Creatures So Huge?

From the Whale to Japanese spider crabs, many deep-sea creatures are unusually huge and gigantic. This phenomenon is called deep-sea gigantism. But what drives it is unknown!

In the deep sea and especially near the polar oceans, some animals seem to get really huge like colossal squids, giant isopods and Japanese spider crabs. Scientists aren’t sure why, but they do have some guesses.

There’s Bergmann’s Rule, for example, which suggests that temperature may influence gigantism. This might be because larger animals have less surface area relative to volume, so they radiate less heat based on their mass and stay warmer in colder climates. Then there’s Kleiber's Law, which states that more massive animals generally have lower metabolic rates and therefore need less high-quality food to survive. Still, other theories suggest that gigantism may help organisms resist increased pressure of the deep sea. But we don’t really have conclusive biological reasons why these giant creatures exist.

So, the ocean is just full of mysteries, maybe because it is so huge and dark and deep. But just so you know that we are not saying that these 7 topics are things that Science Can’t Explain. Instead, you should just think of them as reminders of how much we still have to learn about the ocean.

As our technology improves and our access to the ocean takes us to new depths, we will be able to see and hear and sample more stuff than we ever have before. So in time, these puzzles will be solved, and new creatures will be discovered and our understanding of our planet and the life on it will be that much deeper.

Also Read:- Glimpse Of The Far Side Of The Moon

Read More

5 Unsolved Mysteries About Our Universe

At the beginning of the 20th century, many scientists started thinking that Physics was pretty much over. Surely we have a few unsolved mysteries left but it seemed like they could all be ironed out with better measurements or maybe with very slight tweaks to what was already known.

The problem was, those mysteries didn't go away with better measurements and slight tweaks. They led to fundamental revolutions in our understanding of nature. Huge, important things, like Relativity and Quantum Mechanics.

Now that we have discovered those things, though, It might sometimes feel like there are, once again, just a few small problems left for physicists to solve before we can say we know everything about how the universe works.

Here are 5 of those problems that are actually a really big deal and are not going to go down without a fight:

1.Neutrino Mass

2.Matter-Antimatter Asymmetry

3.Dark Matter

4.Lithium-7

5.Axis Of Evil

1.Neutrino Mass

Neutrinos are tiny sub-atomic particles. There are TRILLIONS of them flying through you every second, but they hardly ever hit one of your atoms. Like, even a 14,000 Metric Ton neutrino detector will only detect a few neutrinos a day. 

As strange as that might be, Physicists mostly understand why Neutrinos don't often interact with ordinary matter. What they don't understand, is why Neutrinos have mass or why that mass is so small?

Particle Physicists use the standard model which uses maths to describe how every known particle interacts with every other known particle. It's one of the most successful models in history. The Standard Model correctly predicts the results of literally trillions of experiments.

Now the problem is, the Standard model also predicts that Neutrinos shouldn't have any mass. But in the 1990's, Physicists studying Neutrinos coming from the sun realized that Neutrinos had to have mass. 

There are a few different kinds of Neutrinos and the researchers found that the Neutrinos coming from the sun were switching types. But they would need mass to be able to do that switching which means that the standard model, has a pretty big hole in it.

Now, there is a way of changing the equation used in the Standard model so that it includes Neutrinos with mass. But on its own, the fact that Neutrinos have mass doesn't necessarily have to be a dealbreaker. But Neutrinos masses are also incredibly tiny compared to every other fundamental particle out there. Electrons are the next lightest particles we have found0 and they are still somewhere between 126,000 and 600 million times heavier than the lightest Neutrinos.

That huge gap makes a lot of Physicists think that fitting Neutrinos with mass into the current Standard Model, is a little bit like shoving sugar packets under the leg of a wobbling table and saying you fixed it. There are a few other possible explanations out there that also fit with the standard model and so far, we have not found any solid evidence to support them.

Other Physicists think that we need to throw out the Standard model altogether and turn to new models to explain the mysterious mass. Another possible solution to the Neutrino mass problem could help solve a second mystery. 

2. Matter-Antimatter Asymmetry

Why is there so much matter in the universe? See, Matter has a sort of twin called Antimatter. Antimatter particles are just like regular matter particles, except they have the opposite charge. So regular matter has electrons, for example, which have a negative charge. But antimatter has what are called positrons, which are just like electrons except with a positive charge and whenever a particle of matter meets its corresponding particle of antimatter, they annihilate each other in a big explosion.

The problem is, Matter and Anti-matter act the same in a lot of ways, as long as they are kept separate from each other. Like, when we do experiments in particle accelerators and produce particles of matter, we produce particles of antimatter too. Antimatter can even make atoms, just like normal matter can.

The laws of Physics just don't seem to prefer one over the other. But when we look out into the universe, all we see is ordinary matter, like the stuff down here on Earth, there are no Antimatter stars, no Antimatter galaxies and no Antimatter dust clouds. If there were, they would occasionally run into similar pieces of matter, and they would annihilate each other in a big flash. But we don't see those flashes.

But why didn't the universe start out with equal amounts of matter and antimatter that then annihilated each other, with nothing left over?

There are a lot of possibilities and some of them have to do with our old friends, Neutrinos: You remember how Neutrinos are so weirdly light? If there are also incredibly heavy Neutrinos, they would balance out the light Neutrinos by creating a whole family that kind of averages out at a more reasonable mass.

These heavy neutrinos would have been around just after the Big Bang when they would have decayed into smaller lighter particles and in the process produced slightly more matter particles than antimatter particles. 

So, if heavy neutrinos did actually exist that could help solve two mysteries at once. First, it might explain why neutrinos have such tiny masses. Second, it would explain why this matter all over the universe instead of antimatter. It would be such a nice elegant solution. The only problem is none of our experiments has found evidence for it. 

3.Dark Matter

Let's zoom way out now from subatomic particles to the whole galaxy. Since gravity comes from mass astronomers can use the amount of matter they detect in the galaxy to calculate how strong its gravity should be. But they have known for almost a century that they must be missing something. 

Stars orbit the centre of galaxies so fast that the galaxies calculated gravity should not be strong enough to hold onto these. Stars should escape into intergalactic space, but they don't. There must be some extra source of gravity out there holding galaxies together.

Astronomers call this source dark matter and unlike antimatter, we have no idea what dark matter is made of. All they really know is that dark matter interacts with regular matter through the gravitational force and it is invisible to telescopes. Also, it makes up about 85% of the matter in the universe. 

Now there is a much simpler possibility, what if astronomers are just wrong about the laws of gravity. Maybe if they found the right laws they could explain everything without needing dark matter. 

But dark matter just explains too many things too well from the way that galaxies are distributed in a large-scale to the way that matter clump together just after the Big Bang. Plus astronomers have actually found pockets of dark matter that are completely separated from any visible matter. In other words, they have seen gravitational effects that should be caused by matter in places where there is no detectable matter even changing the laws of gravity would not explain that so dark matter definitely exists we just don't know what it is? 

But we do know what it is not. For example, lots of people used to think that dark matter was probably just a lot of really dim ordinary matter, like small, failed stars called brown dwarfs or even neutrino. But experiments have ruled out a lot of those sorts of options.

There are still plenty of other ideas out there waiting in the wings for upcoming experiments. But for now, 85% of the matter of the universe remains completely unexplained.

4.Lithium-7

There's also something weird about matter itself. Starting about a second after the Big Bang and lasting for about three minutes protons and neutrons came together in the first-ever atomic nuclei. 

Physicists can use what they know about particle physics in the early universe to predict how much of each element should have formed this way. Hydrogen, for example, has just a single proton in its nucleus and because it is so simple, about 70% of the atoms in the universe should be hydrogen and that's exactly what astronomers see when they look at old stars.

That same model also predicts that protons and neutrons should have come together to form helium about 27% of the time. So, 27 percent of the atoms should have been helium. Again exactly what astronomers see when they check and just about every element they look at matches in the same way and then there is Lithium. 

One form of lithium called lithium-7 has three protons and four neutron and astronomers see four times less of it than the model predicted. This huge difference makes them think there must be something wrong with either with the model or the measurements or both.

Astronomers make a few assumptions about the early universe in order to predict how much of each element was produced. Then, to measure how much of each of those elements is actually out there, they use the light from stars where again, they have to make some assumptions about things like the star's temperature and stability. They could try to change some of those assumptions to fit lithium, but there's a problem these assumptions work so well for the other elements that tweaking them to fit lithium screws everything else up. 

So, a lot of physicists think the lithium problem means that there is some part of physics that we are missing. Like the idea of supersymmetry, which says that every particle has a kind of twin sibling with a much larger mass and there's another idea that the things we think are constants of nature and basically set in stone aren't actually constant. 

If supersymmetry is real that would mean there were more particles in the early universe. And if the things we think are set in stone actually aren't that would change how the particles interacted. So, both could help explain the weird lithium numbers if we ever find evidence for them but so far we haven't found it.

5.Axis Of Evil

The Cosmic Microwave Background or CMB is the oldest light in the universe. It's often represented as a pattern of reds and blues which show the different densities of matter that eventually led to big structures like our galaxy. The CMB was a really important discovery in the 1960s, because it helped confirm the Big Bang Theory. But it also hides an axis of evil and yes that's actually what scientists call it the axis of evil.

See researchers expect that matter in the early universe shouldn't have been bunched up too much in any one place or direction. But that's not what they see in the CMB. Instead, they see a kind of split between a more dense half and a less dense half with an axis of evil' between the two. And when they try to divide up the CMB in other more complicated ways than just seeing which half is denser the axis of evil is still there. 

At first, astronomers thought there must have been something wrong with the measurements or maybe that there was something like a nearby dust cloud that was messing things up. But they have checked and checked and checked and they can't get rid of this. Axis make things even weirder the axis of evil lines up with the plane of our solar system. We point right at it and that's just bizarre. 

Astronomy is guided by something called a Copernican principle which says that there's no reason our place in the universe should be special. But lining up with a cosmological axis that formed billions of years before earth did seems like it puts us in a pretty special place.

Now it's completely possible that there's nothing weird about the alignment at all. There is probably about a 1 in 1,000 chance that the conventional Big Bang model would produce a universe with matter bunched up like it is in the CMB. Those odds aren't too bad and with trillions of planets orbiting trillions of stars throughout the universe someone was bound to line up with the axis of evil.

So, maybe we just got lucky and besides the alignment isn't perfect, it's just surprisingly good. But scientists still want to know why this axis exists and whether there's a reason our solar system lines up with it? Unfortunately, they haven't come up with Much  

None of these mysteries will be easy to solve. But there are lots of smart people working on all of them and sometimes even on two or more at once. So, maybe someday soon we will be telling you about the solutions to some of these problems. But in the meantime, they will keep reminding us that there is still a lot we don't know about the universe.

Also Read:-Glimpse Of The Far Side Of The Moon

Source: NASA, CERN, Wikipedia, Nature

Read More