mass of the sun

anonymous asked:

hi! I was wondering what is the difference between white dwarfs and neutron stars? Oh and, since neutrons stars are called STARS, does that mean that they produce light? If yes, then how? Aren't they made of 100% neutrons?

Put simply, neutron stars are like white dwarfs on steroids. A white dwarf is the “corpse” of a low mass star, like our own Sun. They are usually about the size of a planet, and are incredibly dense. They are almost entirely composed of carbon and oxygen, and are only supported by “electron degeneracy pressure”, which essentially means that the electrons in atoms refuse to get any closer to each other. Since they have no fuel, they only give off light because they are very hot when they are created. They will eventually cool off, and turn into a brown dwarf.

Neutron stars are similar, but are created by the collapse of a much more massive star than our own. Here, the gravity is so strong, not even electron degeneracy pressure can hold the star under its own weight. So, all the electrons fuse with protons to create neutrons (hence the name), and are now supported by neutron degeneracy pressure. These are often much denser and smaller than white dwarfs, being about the size of a city. Like white dwarfs, though, they have no fuel left to spend, and give off light as a result of thermal radiation. As long as they remain isolated, they will eventually cool down and stop giving off light. Thanks for asking!

this website pisses me off, everyones always like “space is so cool!” not its not, space is bullshit and i hate everything about it, i genuinely just saw the phrase “a black hole with a mass two billion times the mass of the sun” im so pissed off, shut the fuck up, dont patronise me scientists you know i dont know what the fuck that means, my sad little brain cant comprehend the mass of one sun let alone two fucking billion, i cant even count past 10 without getting confused and youre out here talking about the mass of two billion fucking suns, shut the hell up. and dont even get me started about black holes or the expansion of the universe because thats another two seperate rants entierly. oh and apparently theres a planet made of ice except the ice is also on fire??? yeah sure fucking thing, scientists. and this is just the shit i know about. i purposely dont research space because it pisses me off so much, god knows what other fucking bullshit exists out there that ive yet to read a fucking wikipedia article about. i dont think space is real, literally everything about space is so fucking fake, this is just some elaborate fucking practicle joke. two billion times the mass of the sun, fuck you

A Total Solar Eclipse Revealed Solar Storms 100 Years Before Satellites

Just days from now, on Aug. 21, 2017, the Moon will pass between the Sun and Earth, casting its shadow down on Earth and giving all of North America the chance to see a solar eclipse. Remember that it is never safe to look at the partially eclipsed or uneclipsed Sun, so make sure you use a solar filter or indirect viewing method if you plan to watch the eclipse.

Eclipses set the stage for historic science. Past eclipses enabled scientists to study the Sun’s structure, find the first proof of Einstein’s theory of general relativity, and discover the element helium — 30 years before it was found on Earth..

We’re taking advantage of the Aug. 21 eclipse by funding 11 ground-based scientific studies. As our scientists prepare their experiments for next week, we’re looking back to an historic 1860 total solar eclipse, which many think gave humanity our first glimpse of solar storms — called coronal mass ejections — 100 years before scientists first understood what they were.  

Coronal mass ejections, or CMEs, are massive eruptions made up of hot gas, plasma and magnetic fields. Bursting from the Sun’s surface, these giant clouds of solar material speed into space up to a million miles per hour and carry enough energy to power the world for 10,000 years if we could harness it. Sometimes, when they’re directed towards Earth, CMEs can affect Earth’s space environment, creating space weather: including triggering auroras, affecting satellites, and – in extreme cases – even straining power grids.

Scientists observed these eruptions in the 1970s during the beginning of the modern satellite era, when satellites in space were able to capture thousands of images of solar activity that had never been seen before.

But in hindsight, scientists realized their satellite images might not be the first record of these solar storms. Hand-drawn records of an 1860 total solar eclipse bore surprising resemblance to these groundbreaking satellite images.

On July 18, 1860, the Moon’s shadow swept across North America, Spain and North Africa. Because it passed over so much populated land, this eclipse was particularly well-observed, resulting in a wealth of scientific observations.  

Drawings from across the path of the 1860 eclipse show large, white finger-like projections in the Sun’s atmosphere—called the corona—as well as a distinctive, bubble-shaped structure. But the observations weren’t uniform – only about two-thirds of the 1860 eclipse sketches showed this bubble, setting off heated debate about what this feature could have been.

Sketches from the total solar eclipse of July 1860.

One hundred years later, with the onset of space-based satellite imagery, scientists got another piece of the puzzle. Those illustrations from the 1860 eclipse looked very similar to satellite imagery showing CMEs – meaning 1860 may have been humanity’s first glimpse at these solar storms, even though we didn’t understand what we were seeing.

While satellites provide most of the data for CME research, total solar eclipses seen from the ground still play an important role in understanding our star. During an eclipse, observers on the ground are treated to unique views of the innermost corona, the region of the solar atmosphere that triggers CMEs.

This region of the Sun’s atmosphere can’t be measured at any other time, since human-made instruments that create artificial eclipses must block out much of the Sun’s atmosphere—as well as its bright face—in order to produce clear images. Yet scientists think this important region is responsible for accelerating CMEs, as well as heating the entire corona to extraordinarily high temperatures.

When the path of an eclipse falls on land, scientists take advantage of these rare chances to collect unique data. With each new total solar eclipse, there’s the possibility of new information and research—and maybe, the chance to reveal something as astronomical as the first solar storm.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21.

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voltron character as stupid shit my friends and i have said
  • Lance: if i was a fruit i'd be a tomato becuase no body realizes that i'm there, in the fruit category
  • Hunk: let's bake cookies with carbonated milk and sell them to raise money for a chemistry field trip
  • Pidge: ah yes, if you take the molar mass of oxygen divided by the radius of the sun multiplied by avagadro's number, then add the square root of the earth's area and finally multiply it by 0 you would get the amount of fucks i give
  • Shiro: ah yes, whats on the agenda today? death? ah perfect
  • Keith: *teacher calls him obtuse as a joke* i know what that means,youre calling me fat
  • Allura: cut off your Fallopian tubes, BAM NO PERIODS!
  • Coran: why do kids get snack time and nap time, they dont even appreciate it. i say we should give the nap times to highschoolers and give the kids our workload instead.
  • Zarkon: hey help me create this huge epidemic that will wipe uot half the population so we can decrease our population bc its scary
  • Haggar: magic is real, just look at the kids who get straight A's
When Dead Stars Collide!

Gravity has been making waves - literally.  Earlier this month, the Nobel Prize in Physics was awarded for the first direct detection of gravitational waves two years ago. But astronomers just announced another huge advance in the field of gravitational waves - for the first time, we’ve observed light and gravitational waves from the same source.

There was a pair of orbiting neutron stars in a galaxy (called NGC 4993). Neutron stars are the crushed leftover cores of massive stars (stars more than 8 times the mass of our sun) that long ago exploded as supernovas. There are many such pairs of binaries in this galaxy, and in all the galaxies we can see, but something special was about to happen to this particular pair.

Each time these neutron stars orbited, they would lose a teeny bit of gravitational energy to gravitational waves. Gravitational waves are disturbances in space-time - the very fabric of the universe - that travel at the speed of light. The waves are emitted by any mass that is changing speed or direction, like this pair of orbiting neutron stars. However, the gravitational waves are very faint unless the neutron stars are very close and orbiting around each other very fast.

As luck would have it, the teeny energy loss caused the two neutron stars to get a teeny bit closer to each other and orbit a teeny bit faster.  After hundreds of millions of years, all those teeny bits added up, and the neutron stars were *very* close. So close that … BOOM! … they collided. And we witnessed it on Earth on August 17, 2017.  

Credit: National Science Foundation/LIGO/Sonoma State University/A. Simonnet

A couple of very cool things happened in that collision - and we expect they happen in all such neutron star collisions. Just before the neutron stars collided, the gravitational waves were strong enough and at just the right frequency that the National Science Foundation (NSF)’s Laser Interferometer Gravitational-Wave Observatory (LIGO) and European Gravitational Observatory’s Virgo could detect them. Just after the collision, those waves quickly faded out because there are no longer two things orbiting around each other!

LIGO is a ground-based detector waiting for gravitational waves to pass through its facilities on Earth. When it is active, it can detect them from almost anywhere in space.

The other thing that happened was what we call a gamma-ray burst. When they get very close, the neutron stars break apart and create a spectacular, but short, explosion. For a couple of seconds, our Fermi Gamma-ray Telescope saw gamma-rays from that explosion. Fermi’s Gamma-ray Burst Monitor is one of our eyes on the sky, looking out for such bursts of gamma-rays that scientists want to catch as soon as they’re happening.

And those gamma-rays came just 1.7 seconds after the gravitational wave signal. The galaxy this occurred in is 130 million light-years away, so the light and gravitational waves were traveling for 130 million years before we detected them.

After that initial burst of gamma-rays, the debris from the explosion continued to glow, fading as it expanded outward. Our Swift, HubbleChandra and Spitzer telescopes, along with a number of ground-based observers, were poised to look at this afterglow from the explosion in ultraviolet, optical, X-ray and infrared light. Such coordination between satellites is something that we’ve been doing with our international partners for decades, so we catch events like this one as quickly as possible and in as many wavelengths as possible.

Astronomers have thought that neutron star mergers were the cause of one type of gamma-ray burst - a short gamma-ray burst, like the one they observed on August 17. It wasn’t until we could combine the data from our satellites with the information from LIGO/Virgo that we could confirm this directly.

This event begins a new chapter in astronomy. For centuries, light was the only way we could learn about our universe. Now, we’ve opened up a whole new window into the study of neutron stars and black holes. This means we can see things we could not detect before.

The first LIGO detection was of a pair of merging black holes. Mergers like that may be happening as often as once a month across the universe, but they do not produce much light because there’s little to nothing left around the black hole to emit light. In that case, gravitational waves were the only way to detect the merger.

Image Credit: LIGO/Caltech/MIT/Sonoma State (Aurore Simonnet)

The neutron star merger, though, has plenty of material to emit light. By combining different kinds of light with gravitational waves, we are learning how matter behaves in the most extreme environments. We are learning more about how the gravitational wave information fits with what we already know from light - and in the process we’re solving some long-standing mysteries!

Want to know more? Get more information HERE.

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anonymous asked:

Pls tell me interesting facts about stars

Interesting facts about stars:

  • Heavy stars blow up and make heavier elements like gold. So, every bit of gold you’ve ever seen, worn, or touched came from the dying explosion of a star. Other elements made in supernovae include anything on the periodic table heavier than iron
  • Heavy stars blow up when they start fusing iron. Meaning, the iron in your frying pan, car, and your blood killed a star at least 3 times the mass of the sun.
  • Some massive stars that die end up compressing all their mass into a star about 6 miles across, or about the size of a city. This is called a neutron star.
    • To put this in perspective, these stars start out 3 times as big as our sun and all of their mass is crushed into something the size of a city. The space between atoms is squished away, and the protons and electrons combine to form neutrons. 
    • Neutron stars are literally as dense as atomic nuclei
  • Most stars come in pairs
  • The most common stellar type is a red dwarf, which is a small, red, dim, cool star.

Honestly, that’s just the first few that come to mind, space is really crazy.

NGC 6334: The Cats Paw Nebula : Nebulas are perhaps as famous for being identified with familiar shapes as perhaps cats are for getting into trouble. Still, no known cat could have created the vast Cat’s Paw Nebula visible in Scorpius. At 5,500 light years distant, Cat’s Paw is an emission nebula with a red color that originates from an abundance of ionized hydrogen atoms. Alternatively known as the Bear Claw Nebula or NGC 6334, stars nearly ten times the mass of our Sun have been born there in only the past few million years. Pictured here is a deep field image of the Cat’s Paw Nebula in light emitted by hydrogen, oxygen, and sulfur. via NASA

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Five Famous Pulsars from the Past 50 Years

Early astronomers faced an obstacle: their technology. These great minds only had access to telescopes that revealed celestial bodies shining in visible light. Later, with the development of new detectors, scientists opened their eyes to other types of light like radio waves and X-rays. They realized cosmic objects look very different when viewed in these additional wavelengths. Pulsars — rapidly spinning stellar corpses that appear to pulse at us — are a perfect example.

The first pulsar was observed 50 years ago on August 6, 1967, using radio waves, but since then we have studied them in nearly all wavelengths of light, including X-rays and gamma rays.

Typical Pulsar

Most pulsars form when a star — between 8 and 20 times the mass of our sun — runs out of fuel and its core collapses into a super dense and compact object: a neutron star

These neutron stars are about the size of a city and can rotate slowly or quite quickly, spinning anywhere from once every few hours to hundreds of times per second. As they whirl, they emit beams of light that appear to blink at us from space.

First Pulsar

One day five decades ago, a graduate student at the University of Cambridge, England, named Jocelyn Bell was poring over the data from her radio telescope - 120 meters of paper recordings.

Image Credit: Sumit Sijher

She noticed some unusual markings, which she called “scruff,” indicating a mysterious object (simulated above) that flashed without fail every 1.33730 seconds. This was the very first pulsar discovered, known today as PSR B1919+21.

Best Known Pulsar

Before long, we realized pulsars were far more complicated than first meets the eye — they produce many kinds of light, not only radio waves. Take our galaxy’s Crab Nebula, just 6,500 light years away and somewhat of a local celebrity. It formed after a supernova explosion, which crushed the parent star’s core into a neutron star. 

The resulting pulsar, nestled inside the nebula that resulted from the supernova explosion, is among the most well-studied objects in our cosmos. It’s pictured above in X-ray light, but it shines across almost the entire electromagnetic spectrum, from radio waves to gamma rays.

Brightest Gamma-ray Pulsar

Speaking of gamma rays, in 2015 our Fermi Gamma-ray Space Telescope discovered the first pulsar beyond our own galaxy capable of producing such high-energy emissions. 

Located in the Tarantula Nebula 163,000 light-years away, PSR J0540-6919 gleams nearly 20 times brighter in gamma-rays than the pulsar embedded in the Crab Nebula.

Dual Personality Pulsar

No two pulsars are exactly alike, and in 2013 an especially fast-spinning one had an identity crisis. A fleet of orbiting X-ray telescopes, including our Swift and Chandra observatories, caught IGR J18245-2452 as it alternated between generating X-rays and radio waves. 

Scientists suspect these radical changes could be due to the rise and fall of gas streaming onto the pulsar from its companion star.

Transformer Pulsar

This just goes to show that pulsars are easily influenced by their surroundings. That same year, our Fermi Gamma Ray Space Telescope uncovered another pulsar, PSR J1023+0038, in the act of a major transformation — also under the influence of its nearby companion star. 

The radio beacon disappeared and the pulsar brightened fivefold in gamma rays, as if someone had flipped a switch to increase the energy of the system. 

NICER Mission

Our Neutron star Interior Composition Explorer (NICER) mission, launched this past June, will study pulsars like those above using X-ray measurements.

With NICER’s help, scientists will be able to gaze even deeper into the cores of these dense and mysterious entities.

For more information about NICER, visit https://www.nasa.gov/nicer

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Astronomy and Astrophysics: Facts

Here is a list of some curiosities of astronomy and astrophysics. From our solar system to interstellar space.

Ganymede - Ganymede is the largest and most massive moon of Jupiter and in the Solar System. It has a diameter of 5,268 km and is 8% larger than the planet Mercury. Is the only moon known to have a magnetic field.

Supersonic Wind - Neptune, the eighth and farthest planet from the sun, has the strongest winds in the solar system. At high altitudes speeds can exceed 1,100 mph. That is 1.5 times faster than the speed of sound. 

Io - Jupiter’s moon Io is the most volcanically active world in the Solar System, with hundreds of volcanoes, some erupting lava fountains dozens of miles (or kilometers) high. Io is caught in a tug-of-war between Jupiter’s massive gravity and the smaller but precisely timed pulls from two neighboring moons that orbit further from Jupiter - Europa and Ganymede. 

Magnetosphere of Jupiter - The stronger the magnetic field, the larger the magnetosphere. Some 20,000 times stronger than Earth’s magnetic field, Jupiter’s magnetic field creates a magnetosphere so large it begins to avert the solar wind almost 3 million kilometers before it reaches Jupiter. The magnetosphere extends so far past Jupiter it sweeps the solar wind as far as the orbit of Saturn. 

A scary future: Sun - A red giant star is a dying star in the last stages of stellar evolution. In only a few billion years, our own sun will turn into a red giant star, expand and engulf the inner planets, possibly even Earth. 

Supernova - Supernovas can briefly outshine entire galaxies and radiate more energy than our sun will in its entire lifetime. 

OJ 287 - The rotational rate of this massive black hole is one third of the maximum spin rate allowed in General Relativity. This 18 billion-solar-mass black hole powers a quasar called OJ 287 which lies about 3.5 billion light-years away from Earth. 

Olympus Mons - Olympus Mons is a big volcano. It is almost unimaginably huge. It is 550 kilometers (342 miles) across at its base, and the volcanic crater (the technical term is ‘caldera’) at the peak is 80 kilometers (53 miles) long. If you were standing at the edge of the caldera, the volcano is so broad and the slopes are so gradual that the base of the volcano would be beyond the horizon. That’s right, it is a volcano so big that it curves with the surface of the planet. 

Neutron star - A neutron star has a mass of about 1.4 times the mass of the sun, but is not much bigger than a small city, about 15 km in radius. A teaspoon of neutron star material would weigh about 10 million tons. The gravitational field is intense; the escape velocity is about 0.4 times the speed of light. The collapsed star is so dense that electrons and protons do not exist separately, but are fused to form neutrons. The outer layers form a rigid crust surrounded by an atmosphere of a highly energetic electrons and excited atoms. 

Gravitational waves - Gravitational waves are ‘ripples’ in the fabric of space-time caused by some of the most violent and energetic processes in the Universe. Albert Einstein predicted the existence of gravitational waves in 1916 in his general theory of relativity. Einstein’s mathematics showed that massive accelerating objects (such as neutron stars or black holes orbiting each other) would disrupt space-time in such a way that 'waves’ of distorted space would radiate from the source (like the movement of waves away from a stone thrown into a pond). 

Sources: Wikipedia , laspe.colorad, nasa.com, Futurism.com, LIGO & Universetoday.com

psa

Black holes do not “suck,” they pull via gravity, like the earth and the sun. They aren’t vacuum cleaners and “sucking” is the wrong word to use. They pull things in. 

also, if the sun were to suddenly collapse into a black hole, nothing would change since the sun’s mass would equal the black hole’s mass. the earth and all the other planets would continue to orbit, except they’d be orbiting a sun-mass black hole instead. 

Thank you for your time.

M2 9: Wings of a Butterfly Nebula : Are stars better appreciated for their art after they die? Actually, stars usually create their most artistic displays as they die. In the case of low-mass stars like our Sun and M2-9 pictured above, the stars transform themselves from normal stars to white dwarfs by casting off their outer gaseous envelopes. The expended gas frequently forms an impressive display called a planetary nebula that fades gradually over thousands of years. M2-9, a butterfly planetary nebula 2100 light-years away shown in representative colors, has wings that tell a strange but incomplete tale. In the center, two stars orbit inside a gaseous disk 10 times the orbit of Pluto. The expelled envelope of the dying star breaks out from the disk creating the bipolar appearance. Much remains unknown about the physical processes that cause planetary nebulae. via NASA

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Neutron Stars Are Weird!

There, we came right out and said it. They can’t help it; it’s just what happens when you have a star that’s heavier than our sun but as small as a city. Neutron stars give us access to crazy conditions that we can’t study directly on Earth.

Here are five facts about neutron stars that show sometimes they are stranger than science fiction!

1. Neutron stars start their lives with a bang

When a star bigger and more massive than our sun runs out of fuel at the end of its life, its core collapses while the outer layers are blown off in a supernova explosion. What is left behind depends on the mass of the original star. If it’s roughly 7 to 19 times the mass of our sun, we are left with a neutron star. If it started with more than 20 times the mass of our sun, it becomes a black hole.

2. Neutron stars contain the densest material that we can directly observe

While neutron stars’ dark cousins, black holes, might get all the attention, neutron stars are actually the densest material that we can directly observe. Black holes are hidden by their event horizon, so we can’t see what’s going on inside. However, neutron stars don’t have such shielding. To get an idea of how dense they are, one sugar cube of neutron star material would weigh about 1 trillion kilograms (or 1 billion tons) on Earth—about as much as a mountain. That is what happens when you cram a star with up to twice the mass of our sun into a sphere the diameter of a city.

3. Neutron stars can spin as fast as blender blades

Some neutron stars, called pulsars, emit streams of light that we see as flashes because the beams of light sweep in and out of our vision as the star rotates. The fastest known pulsar, named PSR J1748-2446ad, spins 43,000 times every minute. That’s twice as fast as the typical household blender! Over weeks, months or longer, pulsars pulse with more accuracy than an atomic clock, which excites astronomers about the possible applications of measuring the timing of these pulses.

4. Neutron stars are the strongest known magnets

Like many objects in space, including Earth, neutron stars have a magnetic field. While all known neutron stars have magnetic fields billions and trillions of times stronger than Earth’s, a type of neutron star known as a magnetar can have a magnetic field another thousand times stronger. These intense magnetic forces can cause starquakes on the surface of a magnetar, rupturing the star’s crust and producing brilliant flashes of gamma rays so powerful that they have been known to travel thousands of light-years across our Milky Way galaxy, causing measurable changes to Earth’s upper atmosphere.

5. Neutron stars’ pulses were originally thought to be possible alien signals

Beep. Beep. Beep. The discovery of pulsars began with a mystery in 1967 when astronomers picked up very regular radio flashes but couldn’t figure out what was causing them. The early researchers toyed briefly with the idea that it could be a signal from an alien civilization, an explanation that was discarded but lingered in their nickname for the original object—LGM-1, a nod to the “little green men” (it was later renamed PSR B1919+21). Of course, now scientists understand that pulsars are spinning neutron stars sending out light across a broad range of wavelengths that we detect as very regular pulses – but the first detections threw observers for a loop.

The Neutron star Interior Composition Explorer (NICER) payload that is soon heading to the International Space Station will give astronomers more insight into neutron stars—helping us determine what is under the surface. Also, onboard NICER, the Station Explorer for X-ray Timing and Navigation Technology (SEXTANT) experiment will test the use of pulsars as navigation beacons in space.

Want to learn even more about Neutron Stars? Watch this…

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A Starry Night of Iceland : On some nights, the sky is the best show in town. On this night, the sky was not only the best show in town, but a composite image of the sky won an international competition for landscape astrophotography. The featured winning image was taken in 2011 over Jkulsrln, the largest glacial lake in Iceland. The photographer combined six exposures to capture not only two green auroral rings, but their reflections off the serene lake. Visible in the distant background sky is the band of our Milky Way Galaxy and the Andromeda galaxy. A powerful coronal mass ejection from the Sun caused auroras to be seen as far south as Wisconsin, USA. Solar activity over the past week has resulted in auroras just over the past few days. via NASA

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Our sun is dynamic and ever-changing. On Friday, July 14, a solar flare and a coronal mass ejection erupted from the same, large active region. The coils arcing over this active region are particles spiraling along magnetic field lines.

Solar flares are explosions on the sun that send energy, light and high-speed particles into space. Such flares are often associated with solar magnetic storms known as coronal mass ejections. While these are the most common solar events, the sun can also emit streams of very fast protons – known as solar energetic particle (SEP) events – and disturbances in the solar wind known as corotating interaction regions (CIRs).

Learn more HERE.

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The Swirling Core of the Crab Nebula : At the core of the Crab Nebula lies a city-sized, magnetized neutron star spinning 30 times a second. Known as the Crab Pulsar, its actually the rightmost of two bright stars, just below a central swirl in this stunning Hubble snapshot of the nebulas core. Some three light-years across, the spectacular picture frames the glowing gas, cavities and swirling filaments bathed in an eerie blue light. The blue glow is visible radiation given off by electrons spiraling in a strong magnetic field at nearly the speed of light. Like a cosmic dynamo the pulsar powers the emission from the nebula, driving a shock wave through surrounding material and accelerating the spiraling electrons. With more mass than the Sun and the density of an atomic nucleus, the spinning pulsar is the collapsed core of a massive star that exploded. The Crab Nebula is the expanding remnant of the stars outer layers. The supernova explosion was witnessed on planet Earth in the year 1054. via NASA

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