Planet: Saturn

What are brown dwarfs?

In order to understand what is a brown dwarf, we need to understand the difference between a star and a planet. It is not easy to tell a star from a planet when you look up at the night sky with your eyes. However, the two kinds of objects look very different to an astronomer using a telescope or spectroscope. Planets shine by reflected light; stars shine by producing their own light. So what makes some objects shine by themselves and other objects only reflect the light of some other body? That is the important difference to understand – and it will allow us to understand brown dwarfs as well.

As a star forms from a cloud of contracting gas, the temperature in its center becomes so large that hydrogen begins to fuse into helium – releasing an enormous amount of energy which causes the star to begin shining under its own power. A planet forms from small particles of dust left over from the formation of a star. These particles collide and stick together. There is never enough temperature to cause particles to fuse and release energy. In other words, a planet is not hot enough or heavy enough to produce its own light.

Brown dwarfs are objects which have a size between that of a giant planet like Jupiter and that of a small star. In fact, most astronomers would classify any object with between 13 times the mass of Jupiter and 75 times the mass of Jupiter to be a brown dwarf. Given that range of masses, the object would not have been able to sustain the fusion of hydrogen like a regular star; thus, many scientists have dubbed brown dwarfs as “failed stars”.

A Trio of Brown Dwarfs

This artist’s conception illustrates what brown dwarfs of different types might look like to a hypothetical interstellar traveler who has flown a spaceship to each one. Brown dwarfs are like stars, but they aren’t massive enough to fuse atoms steadily and shine with starlight – as our sun does so well.

On the left is an L dwarf, in the middle is a T dwarf, and on the right is a Y dwarf. The objects are progressively cooler in atmospheric temperatures as you move from left to right. Y dwarfs are the newest and coldest class of brown dwarfs and were discovered by NASA’s Wide-field Infrared Survey Explorer, or WISE. WISE was able to detect these Y dwarfs for the first time because it surveyed the entire sky deeply at the infrared wavelengths at which these bodies emit most of their light. The L dwarf is seen as a dim red orb to the eye. The T dwarf is even fainter and appears with a darker reddish, or magenta, hue. The Y dwarf is dimmer still. Because astronomers have not yet detected Y dwarfs at the visible wavelengths we see with our eyes, the choice of a purple hue is done mainly for artistic reasons. The Y dwarf is also illustrated as reflecting a faint amount of visible starlight from interstellar space.

In this rendering, the traveler’s spaceship is the same distance from each object. This illustrates an unusual property of brown dwarfs – that they all have the same dimensions, roughly the size of the planet Jupiter, regardless of their mass. This mass disparity can be as large as fifteen times or more when comparing an L to a Y dwarf, despite the fact that both objects have the same radius. The three brown dwarfs also have very different atmospheric temperatures. A typical L dwarf has a temperature of 2,600 degrees Fahrenheit (1,400 degrees Celsius). A typical T dwarf has a temperature of 1,700 degrees Fahrenheit (900 degrees Celsius). The coldest Y dwarf so far identified by WISE has a temperature of less than about 80 degrees Fahrenheit (25 degrees Celsius).

Sources: starchild.gsfc.nasa.gov & nasa.gov 

 image credit: NASA / JPL-Caltech

Discovering the Universe Through the Constellation Orion

Do you ever look up at the night sky and get lost in the stars? Maybe while you’re stargazing, you spot some of your favorite constellations. But did you know there’s more to constellations than meets the eye? They’re not just a bunch of imaginary shapes made up of stars — constellations tell us stories about the universe from our perspective on Earth.

What is a constellation?

A constellation is a named pattern of stars that looks like a particular shape. Think of it like connecting the dots. If you join the dots — stars, in this case — and use your imagination, the picture would look like an object, animal, or person. For example, the ancient Greeks believed an arrangement of stars in the sky looked like a giant hunter with a sword attached to his belt, so they named it after a famous hunter in their mythology, Orion. It’s one of the most recognizable constellations in the night sky and can be seen around the world. The easiest way to find Orion is to go outside on a clear night and look for three bright stars close together in an almost-straight line. These three stars represent Orion's belt. Two brighter stars to the north mark his shoulders, and two more to the south represent his feet.

Credit: NASA/STScI

Over time, cultures around the world have had different names and numbers of constellations depending on what people thought they saw. Today, there are 88 officially recognized constellations. Though these constellations are generally based on what we can see with our unaided eyes, scientists have also invented unofficial constellations for objects that can only be seen in gamma rays, the highest-energy form of light.

Perspective is everything

The stars in constellations may look close to each other from our point of view here on Earth, but in space they might be really far apart. For example, Alnitak, the star at the left side of Orion's belt, is about 800 light-years away. Alnilam, the star in the middle of the belt, is about 1,300 light-years away. And Mintaka, the star at the right side of the belt, is about 900 light-years away. Yet they all appear from Earth to have the same brightness. Space is three-dimensional, so if you were looking at the stars that make up the constellation Orion from another part of our galaxy, you might see an entirely different pattern!

The superstars of Orion

Now that we know a little bit more about constellations, let’s talk about the supercool cosmic objects that form them – stars! Though over a dozen stars make up Orion, two take center stage. The red supergiant Betelgeuse (Orion's right shoulder) and blue supergiant Rigel (Orion's left foot) stand out as the brightest members in the constellation.

Credit: Derrick Lim

Betelgeuse is a young star by stellar standards, about 10 million years old, compared to our nearly 5 billion-year-old Sun. The star is so huge that if it replaced the Sun at the center of our solar system, it would extend past the main asteroid belt between Mars and Jupiter! But due to its giant mass, it leads a fast and furious life.

Betelgeuse is destined to end in a supernova blast. Scientists discovered a mysterious dimming of Betelgeuse in late 2019 caused by a traumatic outburst that some believed was a precursor to this cosmic event. Though we don’t know if this incident is directly related to an imminent supernova, there’s a tiny chance it might happen in your lifetime. But don't worry, Betelgeuse is about 550 light-years away, so this event wouldn't be dangerous to us – but it would be a spectacular sight.

Rigel is also a young star, estimated to be 8 million years old. Like Betelgeuse, Rigel is much larger and heavier than our Sun. Its surface is thousands of degrees hotter than Betelgeuse, though, making it shine blue-white rather than red. These colors are even noticeable from Earth. Although Rigel is farther from Earth than Betelgeuse (about 860 light-years away), it is intrinsically brighter than its companion, making it the brightest star in Orion and one of the brightest stars in the night sky.

Credit: Rogelio Bernal Andreo

Buckle up for Orion’s belt

Some dots that make up constellations are actually more than one star, but from a great distance they look like a single object. Remember Mintaka, the star at the far right side of Orion's belt? It is not just a single star, but actually five stars in a complex star system.

Credit: X-ray: NASA/CXC/GSFC/M. Corcoran et al.; Optical: Eckhard Slawik

Sword or a stellar nursery?

Below the three bright stars of Orion’s belt lies his sword, where you can find the famous Orion Nebula. The nebula is only 1,300 light-years away, making it the closest large star-forming region to Earth. Because of its brightness and prominent location just below Orion’s belt, you can actually spot the Orion Nebula from Earth! But with a pair of binoculars, you can get a much more detailed view of the stellar nursery. It’s best visible in January and looks like a fuzzy “star” in the middle of Orion’s sword.

More to discover in constellations

In addition to newborn stars, Orion also has some other awesome cosmic objects hanging around. Scientists have discovered exoplanets, or planets outside of our solar system, orbiting stars there. One of those planets is a giant gas world three times more massive than Jupiter. It’s estimated that on average there is at least one planet for every star in our galaxy. Just think of all the worlds you may be seeing when you look up at the night sky!

It’s also possible that the Orion Nebula might be home to a black hole, making it the closest known black hole to Earth. Though we may never detect it, because no light can escape black holes, making them invisible. However, space telescopes with special instruments can help find black holes. They can observe the behavior of material and stars that are very close to black holes, helping scientists find clues that can lead them closer to discovering some of these most bizarre and fascinating objects in the cosmos.

Next time you go stargazing, remember that there’s more to the constellations than meets the eye. Let them guide you to some of the most incredible and mysterious objects of the cosmos — young stars, brilliant nebulae, new worlds, star systems, and even galaxies!

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How quickly do we grow accustomed to wonders. I am reminded of the Isaac Asimov story "Nightfall," about the planet where the stars were visible only once in a thousand years. So awesome was the sight that it drove men mad. We who can see the stars every night glance up casually at the cosmos and then quickly down again, searching for a Dairy Queen. (x)

I had a really stupid idea and had to paint it for a friend.

Stars

Stars are the most widely recognized astronomical objects, and represent the most fundamental building blocks of galaxies. The age, distribution, and composition of the stars in a galaxy trace the history, dynamics, and evolution of that galaxy. Moreover, stars are responsible for the manufacture and distribution of heavy elements such as carbon, nitrogen, and oxygen, and their characteristics are intimately tied to the characteristics of the planetary systems that may coalesce about them. Consequently, the study of the birth, life, and death of stars is central to the field of astronomy.

How do stars form?

Stars are born within the clouds of dust and scattered throughout most galaxies. A familiar example of such as a dust cloud is the Orion Nebula.

Turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. As the cloud collapses, the material at the center begins to heat up. Known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star.

Three-dimensional computer models of star formation predict that the spinning clouds of collapsing gas and dust may break up into two or three blobs; this would explain why the majority the stars in the Milky Way are paired or in groups of multiple stars.

As the cloud collapses, a dense, hot core forms and begins gathering dust and gas. Not all of this material ends up as part of a star — the remaining dust can become planets, asteroids, or comets or may remain as dust.

In some cases, the cloud may not collapse at a steady pace. In January 2004, an amateur astronomer, James McNeil, discovered a small nebula that appeared unexpectedly near the nebula Messier 78, in the constellation of Orion. When observers around the world pointed their instruments at McNeil’s Nebula, they found something interesting — its brightness appears to vary. Observations with NASA’s Chandra X-ray Observatory provided a likely explanation: the interaction between the young star’s magnetic field and the surrounding gas causes episodic increases in brightness.

Main Sequence Stars

A star the size of our Sun requires about 50 million years to mature from the beginning of the collapse to adulthood. Our Sun will stay in this mature phase (on the main sequence as shown in the Hertzsprung-Russell Diagram) for approximately 10 billion years.

Stars are fueled by the nuclear fusion of hydrogen to form helium deep in their interiors. The outflow of energy from the central regions of the star provides the pressure necessary to keep the star from collapsing under its own weight, and the energy by which it shines.

As shown in the Hertzsprung-Russell Diagram, Main Sequence stars span a wide range of luminosities and colors, and can be classified according to those characteristics. The smallest stars, known as red dwarfs, may contain as little as 10% the mass of the Sun and emit only 0.01% as much energy, glowing feebly at temperatures between 3000-4000K. Despite their diminutive nature, red dwarfs are by far the most numerous stars in the Universe and have lifespans of tens of billions of years.

On the other hand, the most massive stars, known as hypergiants, may be 100 or more times more massive than the Sun, and have surface temperatures of more than 30,000 K. Hypergiants emit hundreds of thousands of times more energy than the Sun, but have lifetimes of only a few million years. Although extreme stars such as these are believed to have been common in the early Universe, today they are extremely rare - the entire Milky Way galaxy contains only a handful of hypergiants.

Stars and Their Fates

In general, the larger a star, the shorter its life, although all but the most massive stars live for billions of years. When a star has fused all the hydrogen in its core, nuclear reactions cease. Deprived of the energy production needed to support it, the core begins to collapse into itself and becomes much hotter. Hydrogen is still available outside the core, so hydrogen fusion continues in a shell surrounding the core. The increasingly hot core also pushes the outer layers of the star outward, causing them to expand and cool, transforming the star into a red giant.

If the star is sufficiently massive, the collapsing core may become hot enough to support more exotic nuclear reactions that consume helium and produce a variety of heavier elements up to iron. However, such reactions offer only a temporary reprieve. Gradually, the star’s internal nuclear fires become increasingly unstable - sometimes burning furiously, other times dying down. These variations cause the star to pulsate and throw off its outer layers, enshrouding itself in a cocoon of gas and dust. What happens next depends on the size of the core.

Average Stars Become White Dwarfs

For average stars like the Sun, the process of ejecting its outer layers continues until the stellar core is exposed. This dead, but still ferociously hot stellar cinder is called a White Dwarf. White dwarfs, which are roughly the size of our Earth despite containing the mass of a star, once puzzled astronomers - why didn’t they collapse further? What force supported the mass of the core? Quantum mechanics provided the explanation. Pressure from fast moving electrons keeps these stars from collapsing. The more massive the core, the denser the white dwarf that is formed. Thus, the smaller a white dwarf is in diameter, the larger it is in mass! These paradoxical stars are very common - our own Sun will be a white dwarf billions of years from now. White dwarfs are intrinsically very faint because they are so small and, lacking a source of energy production, they fade into oblivion as they gradually cool down. This fate awaits only those stars with a mass up to about 1.4 times the mass of our Sun. Above that mass, electron pressure cannot support the core against further collapse. Such stars suffer a different fate as described below.

Supernovae Leave Behind Neutron Stars or Black Holes 

Main sequence stars over eight solar masses are destined to die in a titanic explosion called a supernova. A supernova is not merely a bigger nova. In a nova, only the star’s surface explodes. In a supernova, the star’s core collapses and then explodes. In massive stars, a complex series of nuclear reactions leads to the production of iron in the core. Having achieved iron, the star has wrung all the energy it can out of nuclear fusion - fusion reactions that form elements heavier than iron actually consume energy rather than produce it. The star no longer has any way to support its own mass, and the iron core collapses. In just a matter of seconds the core shrinks from roughly 5000 miles across to just a dozen, and the temperature spikes 100 billion degrees or more. The outer layers of the star initially begin to collapse along with the core, but rebound with the enormous release of energy and are thrown violently outward. Supernovae release an almost unimaginable amount of energy. For a period of days to weeks, a supernova may outshine an entire galaxy. Likewise, all the naturally occurring elements and a rich array of subatomic particles are produced in these explosions. On average, a supernova explosion occurs about once every hundred years in the typical galaxy. About 25 to 50 supernovae are discovered each year in other galaxies, but most are too far away to be seen without a telescope.

Neutron Stars

If the collapsing stellar core at the center of a supernova contains between about 1.4 and 3 solar masses, the collapse continues until electrons and protons combine to form neutrons, producing a neutron star. Neutron stars are incredibly dense - similar to the density of an atomic nucleus. Because it contains so much mass packed into such a small volume, the gravitation at the surface of a neutron star is immense.

Neutron stars also have powerful magnetic fields which can accelerate atomic particles around its magnetic poles producing powerful beams of radiation. Those beams sweep around like massive searchlight beams as the star rotates. If such a beam is oriented so that it periodically points toward the Earth, we observe it as regular pulses of radiation that occur whenever the magnetic pole sweeps past the line of sight. In this case, the neutron star is known as a pulsar.

Black Holes

If the collapsed stellar core is larger than three solar masses, it collapses completely to form a black hole: an infinitely dense object whose gravity is so strong that nothing can escape its immediate proximity, not even light. Since photons are what our instruments are designed to see, black holes can only be detected indirectly. Indirect observations are possible because the gravitational field of a black hole is so powerful that any nearby material - often the outer layers of a companion star - is caught up and dragged in. As matter spirals into a black hole, it forms a disk that is heated to enormous temperatures, emitting copious quantities of X-rays and Gamma-rays that indicate the presence of the underlying hidden companion.

From the Remains, New Stars Arise

The dust and debris left behind by novae and supernovae eventually blend with the surrounding interstellar gas and dust, enriching it with the heavy elements and chemical compounds produced during stellar death. Eventually, those materials are recycled, providing the building blocks for a new generation of stars and accompanying planetary systems.

Credit and reference: science.nasa.gov 

image credit: ESO, NASA, ESA, Hubble

Eclipsing Suns

I can’t remember which novel JR said influenced the world of S6, but I was recently reminded of Asimov’s Nightfall and wonder whether its eclipse narrative might have some bearing on the plot …

[Spoilers for Nightfall ahead – highly recommend you read the story (it’s short!)]

For anyone not familiar, Nightfall is set on a planet with six suns - enough suns that the planet never experiences darkness. Every 2000 years or so, the suns and the planet’s moon align just so, and an eclipse occurs. And every 2000 years, something cataclysmic occurs that ends civilization. The only records of the event are embedded in the mythology of an ancient cult’s scripture. 

During one of these cycles, a team of astronomers and psychologists collaborate with the cult, and together determine that they are weeks away from the next eclipse. The scientists lock their loved ones away in a bunker and prepare equipment to document the eclipse, which they do not believe they will survive. (Having never experienced nighttime, they have a pathological fear of the dark. Even more concerning, however, is the threat of the Stars mentioned in ancient scripture, for these have the power to burn cities and drive men to madness.)

And when the eclipse occurs and people see the night sky for the first time in two thousand years, they are struck with terror and knowledge of their insignificance, and all the world over, people set their cities on fire to blot out the stars’ truth and the horror of the long night.

… What little we do know about S6 reminds me of this. Like Clarke and co., these scientists attempt to learn what happened to a lost civilization (Eligius III) while hampered by a cult-like organization (Second Dawn? Wonkru? Whoever now inhabits the planet?) that has attached mythological meaning to the natural phenomenon of the eclipse. JR has said that something crucial happens when the suns eclipse, and though suns eclipsing themselves does not create total darkness, as here, we can guess that there will be psychological ramifications attached to it.

I’ve just made a behavioral study on birds (aka. I’ve fed bread to pigeons and crows) and I’d like to conserve the results for posterity:

Pigeons can and will fight each other for even the smallest crumb of bread

When a pigeon picked up a bread crumb and other pigeons are nearby it will spread its wings to ensure the other pigeons can’t get close enough to steal the crumb™

The other , bread stealing pigeons might also spread their wings to make sure that no pigeon can steal the breadcrumb before them

They will steal it straight from another pigeons beak

Pigeons have no manners

They WILL fly at you and hover around your head once they realized you’re the one throwing the crumbs

They have no concept of personal space.

Crows on the other hand are civilized.

They will try to get to the crumb first but when another crow has reached the crumb before them they will accept this and leave them be

However if a pigeon reaches the crumb first they WILL go absolutely feral and peck the pigeon until it surrenders the crumb

Pigeons are reasonably scared of crows and won’t try to steal crumbs from their very pointy stabby beaks

Crows will wait for you to throw the crumbs at an appropriate distance because they do have manners

Unlike pigeons they will also watch you and look right into your eyes, expectantly

If a crow looks at you , waiting, and you throw it a crumb it will try to catch it just like a dog would

Pigeons however don’t notice shit until it lies in front of their face or they see another pigeon found something

Crows understand pointing, pigeons don’t

If the crows are satisfied they will fly away

Pigeons are never satisfied and therefore will bother you until the very end (aka. Until you don’t have any bread left)

They always hunger.

In conclusion:

Feeding crows is more fun than feeding pigeons because crows know the rules of society and pigeons don’t.

(Next Time on “birdhavioral studies” : “why seagulls fear neither god nor devil” )

Prometheus and Pandora shepherd Saturn’s F ring into shape

Image credit: Morphics Zero

TOP 10 PREHISTORIC OCEAN PREDATORS

10. ANOMALOCARIS (~ 525 Ma) This one metre long invertebrate surely deserves to be included on the list, being one of the first complex oceanic predators to ever have existed. Anomalocaris stalked the Cambrian oceans, viewing the world with a deadly new evolutionary innovation - eyes. Complex eyes allowed this creature to storm its way to the top of the food chain, and with powerful appendages covered in spines it had no trouble devouring prey with tough carapaces. Whilst Anomalocaris is dwarfed by the other contenders on this list, it was still over 10 times larger than any other animal of its time.

9. KRONOSAURUS (125-99 Ma) Kronosaurus, a Cretaceous mosasaur, is named after the Greek titan, Cronus. Its name is well deserved as this ancient beast was a remarkably powerful being. Kronosaurus could reach up to 10 metres long and had a mouth full of sharp, conical teeth. Unlike most other mosasaurs its tail was relatively short, however, evidence shows that Kronosaurus has immensely powerful fins and a pectoral girdle making it an impressive swimmer and hunter.

8. HELICOPRION (290-250 Ma) Helicoprion has astounded scientists since its discovery over 100 years ago. It is iconic for its bizarre spiral of teeth, there are still debates on where exactly these teeth where on the shark with proposals stating they were inside the mouth, on the tip of the tail, the dorsal fin or hanging under the jaw. The most commonly accepted location of the teeth is inside the lower jaw enabling Helicoprion to cleanly slice its prey into pieces.

7. XIPHACTINUS (~110-70 Ma) Xiphactinus was an extraordinary fish that lived during the Cretaceous. It was an esteemed predator that could reach an incredible 6 metres in length and specimens are renowned for their stunning preservation. One such example was 4 metres long and found with another exceptionally well preserved fish just short of 2 metres inside it implying that this particular Xiphactinus individual died shortly after its last feast. Xiphactinus had immensely sharp, slim teeth and an unmistakable underbite which was a possible aid when snaring creatures from below.

6. TYLOSAURUS (86-75 Ma) Tylosaurus is considered a mosasaur and was a vivacious predator all be it smaller than its relative Mosasaurus. Tylosaurus could reach up to 15 metres in length and was one of the apex predators of its day. Fossilised stomach contents of Tylosaurus contain fish, sharks, turtles and other marine reptiles. Despite having an impressive set of teeth, the frontal areas of the jaws exhibit a large reduction in tooth size as well as a more heavily reinforced snout in comparison to other mosasaurs suggesting that Tylosaurus may have rammed into victims with immense force damaging prey internally.

5. MOSASAURUS (70-66 Ma) The mosasaurs ruled the Cretaceous oceans and Mosasaurus was no exception. It could reach up to 17 metres long, longer than most other mosasaurs. Mosasaurus had a strong jaw packed with numerous conical teeth, bite marks of which have been found in huge prehistoric turtles and ammonites suggesting that Mosasaurus was a formidable hunter capable of catching large prey. Mosasaurus was a profound swimmer with strong paddle-like limbs and a huge tail capable of rapidly accelerating the animal when required.

4. DUNKLEOSTEUS (382-358 Ma) Dunkleosteus terrorised the oceans around 370 million years ago and was part of a dynasty known as the placoderm fish (meaning armoured). Dunkleosteus could reach a whopping 6-10 metres in length and probably weighed over a ton. The skull was made up of huge, solid bony plates giving unrivalled protection allowing them to dominate the oceans. Placoderm fish were some of the first organisms to have a mobile jaw, as can be seen in Dunkleosteus’ impressive shearing plates which were used to slice cleanly through prey. Despite an revolutionary jaw, Dunkleosteus could not chew and several fossilised regurgitated remains of its meals have been found that the giant fish simply could not stomach.  

3. DAKOSAURUS (157-137 Ma) Dakosaurus was the largest of a group of marine reptiles that were distant relatives of crocodiles. Dakosaurus could reach up to 5 metres long and had a streamlined body with large paddle-like fins and a long muscular tail implying that is was a very efficient swimmer. The diet of Dakosaurus consisted mostly of fish. The teeth of Dakosaurus are lateromedially compressed and serrated which is a similar morphology to modern killer whales indicating that Dakosaurus was an apex predator of the Jurassic oceans. Skull fenestrae provides evidence that Dakosaurus had very large adductor muscles (which are responsible for the jaw closing) and so it was certainly capable of a forceful bite.

2. LIOPLEURODON (160-155 Ma) Liopleurodon stormed the Jurassic oceans, its huge 7 metre long frame effortlessly cruised through the water. The skull itself could reach a massive 1.5 metres long with a jaw that was packed with teeth up to 10cm long and was capable of an immense bone-crushing force. Liopleurodon was a remarkable hunter with the ability to swim with its nostrils open and so could use its powerful sense of smell to track prey from afar, much like sharks do. Liopleurodon most likely had good camouflage such as a lighter underside and a darker topside so it would blend in with the water to prey above and below.  

1. MEGALODON (~16-2.6 Ma) Megalodon rightfully deserves the top position of the greatest prehistoric ocean predators, ruling the seas for an incredible 14 million years. Megalodon has been estimated to reach up to 18 metres in length and weighing over 40 tonnes. Megalodon is known for its huge 6 inch teeth which were serrated on both sides for an efficient slicing action. Fossils of Megalodon’s prey have also been found, the shark appeared to have adapted its hunting tactics for different sized prey; for smaller prey they would just use their bone crushing bite to pulverise internal organs, but for larger prey they would bite or rip flippers off of creatures to immobilise them and then go in for the kill. The exact bite force of Megalodon has been estimated at around 110,000 N which was more than enough to shatter even the most robust bones. The hunting methods of Megalodon will unfortunately remain a mystery but it was been hypothesised that they swam at great depths and used short bursts of speed to swim up and tear into their preys vulnerable underbelly. Sharks have existed for over 420 million years and still continue to be some of the most successful predators alive, Megalodon is a perfect example of how deadly they can be.

Milky Way’s Central Cluster