Latest Posts by acosmicgeek - Page 3
What a cool illustration :D
It’s true though
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Art by Emanuele Fais
Tonight’s a New Moon!
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You could say that they’re very ... NOBLE!
hehe
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i hope i translated it correctly
Woah :o
So, basically, like the Mission Space ride at Epcot (that one is my favoriteeeee)?
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Testing and Training on the Boeing Starliner : NASA astronaut Mike Fincke works through a check list inside a mockup of Boeing’s CST-100 Starliner during a simulation at NASA’s Johnson Space Center on Aug. 21, 2019. (via NASA)
Aw, now that’s a smart kitty
Also - what’s the meaning of life and death - good question. Cat please explain lol
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Upvote me so that I can post on r/science too.
Oo
I haven’t done a lot of research on comets. Maybe one day I’ll do an article on one, in the future. They sound so cool xD
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Comet Halley vs Comet SWAN via NASA https://ift.tt/2y0UdFr
The pre-dawn hours of May 3rd were moonless as grains of cosmic dust streaked through southern skies above Reunion Island. Swept up as planet Earth plowed through dusty debris streams left behind periodic Comet 1/P Halley, the annual meteor shower is known as the Eta Aquarids. This inspired exposure captures a bright aquarid meteor flashing left to right over a sea of clouds. The meteor streak points back to the shower’s radiant in the constellation Aquarius, well above the eastern horizon and off the top of the frame. Known for speed Eta Aquarid meteors move fast, entering the atmosphere at about 66 kilometers per second, visible at altitudes of 100 kilometers or so. Then about 6 light-minutes from Earth, the pale greenish coma and long tail of Comet C/2020 F8 SWAN were not to be left out of the celestial scene, posing above the volcanic peaks left of center. Now in the northern sky’s morning twilight near the eastern horizon Comet SWAN has not become as bright as anticipated though. This first time comet made its closest approach to planet Earth only two days ago and reaches perihelion on May 27.
(Published May 14, 2020)
Accurate
Even though it’s possible the apple thing never happened.
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Thinking intensifies
Galileo, what a man
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Reality is often disappointing
Wow, that’s gorgeous :o
That’s gotta be one of the most beautiful nebulae I’ve laid eyes on! And, it looks like a heart too!
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IC 1805: The Heart Nebula : What energizes the Heart Nebula? First, the large emission nebula dubbed IC 1805 looks, in whole, like a human heart. The nebula glows brightly in red light emitted by its most prominent element: hydrogen. The red glow and the larger shape are all powered by a small group of stars near the nebula’s center. In the center of the Heart Nebula are young stars from the open star cluster Melotte 15 that are eroding away several picturesque dust pillars with their energetic light and winds. The open cluster of stars contains a few bright stars nearly 50 times the mass of our Sun, many dim stars only a fraction of the mass of our Sun, and an absent microquasar that was expelled millions of years ago. The Heart Nebula is located about 7,500 light years away toward the constellation of Cassiopeia. Coincidentally, a small meteor was captured in the foreground during imaging and is visible above the dust pillars. At the top right is the companion Fishhead Nebula. via NASA
My favorite YouTube video as of now (I know this doesn’t seem like it’s related to space - but it has a nice discussion about black holes and hawking radiation, which is I love it so much)
Remember kids: be cautious of bouncy castles!
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... why.
There are no aliens - so the only thing we could use this as is like a nuke - but that would destroy the entire Earth xD
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THE LIFE OF A STAR: A STAR IS BORN
All you need to make a star is dust, gravity, and time.
Stars form from nebulae's molecular clouds - which are "clumpy, with regions containing a wide range of densities—from a few tens of molecules (mostly hydrogen) per cubic centimetre to more than one million." Stars are only made in the densest regions - cloud cores - and larger cloud cores create more massive stars. Stars also form in associations in these cores. Cores with higher percentages of mass used only for star formation will have more stars bound together, while lower percentages will have stars drifting apart.
These cloud cores rotate very slowly and its mass is highly concentrated in its center - while also spinning and flattening into a disk (Britannica: Star Formation). This concentration is caused by gravity. As the mass of the clump increases - it is very cold and close to absolute zero, which increases density and causes atoms to bind together into molecules such as CO and H2 - it's gravity increases and at a certain point, it will collapse under it (Uoregon). The pressure, spinning, and compressing create kinetic energy which continues to heat the gas and increase density.
Finally, there's the last ingredient: time. The process of these molecular clouds clumping, spinning, concentrating, and collapsing takes quite a while. From start (the cloud core-forming) to finish (the birth of a main-sequence star) - the average time is at about a cool 10 million years (yikes). Of course, this differs with density and mass, but this is the time for a typical solar-type star (StackExchange).
The next stage in a star's life - after the nebulae - is a protostar.
After one clump separates from the cloud core, it develops its own identity and gravity, and loose gas falls into the center. This releases more kinetic energy and heats the gas, as well as the pressure. This clump will collapse under gravity, grow in density in the center. and trap infrared light inside (causing it to become opaque) (Uoregon).
A protostar looks like a normal star - emitting light - but it's just a baby star. Protostars' cores are not hot enough to undergo nuclear fusion and the light they emit (instead of coming from the release of photons after the fusion of atoms) comes from the heat of the protostar as it contracts under gravity. By the time this is formed, the spinning and gravity have flattened the dust and gas into a protostellar disk. The rotation also generates a magnetic field - which generates a protostellar wind - and sometimes even streams or jets of gas into space (LCO).
This protostar, which is not much bigger than Jupiter, continues to grow by taking in more dust and gas. The light emitted absorbs dust and is remitted over and over again, resulting in a shift to longer wavelengths and causing the protostar to emit infrared light. The growth of the star is halted as jets of material stream out from the poles - the cause of this has been unidentified, although theories suggest that strong magnetic fields and rotation "act as whirling rotary blades to fling out the nearby gas." (Britannica: Star Formation)
The "infall" of stars stops by pressure, and the protostar becomes more stable. Eventually, the temperature grows so hot (a few million kelvins) that thermonuclear fusion begins - usually in the form of deuterium (a heavier form of hydrogen), lithium, beryllium, and boron - which radiates light and energy. This starts the pre-main-sequence star phase - also called T Tauri stars - which includes lots of surface activity in the form of flares, stellar winds, opaque circumstellar disks, and stellar jets. In this phase, the star begins to contract - it can lose almost 50% of its mass - and the more massive the star, the shorter the T Tauri phase (Uoregon).
Eventually, when the star's core becomes hot enough (in some cases, we'll touch on this later), it will begin to fuse hydrogen. This will produce "an outward pressure that balances with the inward pressure caused by gravity, stabilizing the star." (Space.com)
This will either create an average-sized star or a massive star.
Nuclear fusion marks the beginning of the main sequence star. A star is born.
But it isn't always.
Now that we've discussed the transition from nebulae to main-sequence star, we'll be talking about what happens when hydrogen fusion doesn't occur. Those are called Brown Dwarfs.
Brown Dwarfs are those stars that form much too small - less than 0.08 the sun's mass - and as a result, they cannot undergo hydrogen fusion (Space.com).
Brown Dwarfs, are, bigger than planets. They are roughly between the size of Jupiter and our sun. Like protostars, brown dwarfs start by fusing deuterium, and their cores contract and increase in heat as they do so. Brown Dwarfs, however, cannot contract to the size required to heat the core enough to fuse hydrogen. Their cores are dense enough to hold themselves up with pressure. They are much colder compared to main-sequence stars, ranging from 2,800 K to 300 K (the sun is 5,800 K). They are called "Brown Dwarfs" because objects below 2,200 often cold too much and develop minerals in their atmosphere, turning a brown-red color (Britannica: Brown Dwarf).
Once Brown Dwarfs have fused all of their deuterium, they glow infrared, and the force of gravity overcomes internal pressure (the internal force of nuclear fusion used to keep it stable) as it slowly collapses. They eventually cool down and become dark balls of gas - black dwarfs (NRAO).
Now that we've covered how stars form - and what happens in certain cases where they are not - we'll be moving to the actual life of a star. Before we talk about the end of a star's life (arguably - my favorite part) we need to discuss main-sequence, cycles, mass, heat, pressure, structure, and more. This is to understand how a star died the way it did.
Because - when it comes to the menu of star death - stars have a few options to choose from.
First - Chapter 1: An Introduction
Previous - Chapter 3: Star Nurseries
Next - Chapter 5: A Day in the Life
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I felt that
I mean they are pretty connected, so even if you choose one you’ll probably have to deal with the other.
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Can I have both?
Ooo, that’s pretty cool
Also - a nice little teaser - we’ll be covering brown dwarfs in the next chapter of the Life of a Star!
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ASTRONOMERS FIND JUPITER-LIKE CLOUD BANDS ON CLOSEST BROWN DWARF
A team of astronomers has discovered that the closest known brown dwarf, Luhman 16A, shows signs of cloud bands similar to those seen on Jupiter and Saturn. This is the first time scientists have used the technique of polarimetry to determine the properties of atmospheric clouds outside of the solar system, or exoclouds.
Brown dwarfs are objects heavier than planets but lighter than stars, and typically have 13 to 80 times the mass of Jupiter. Luhman 16A is part of a binary system containing a second brown dwarf, Luhman 16B. At a distance of 6.5 light-years, it’s the third closest system to our Sun after Alpha Centauri and Barnard’s Star. Both brown dwarfs weigh about 30 times as much as Jupiter.
Despite the fact that Luhman 16A and 16B have similar masses and temperatures (about 1,900°F, or 1,000°C), and presumably formed at the same time, they show markedly different weather. Luhman 16B shows no sign of stationary cloud bands, instead exhibiting evidence of more irregular, patchy clouds. Luhman 16B therefore has noticeable brightness variations as a result of its cloudy features, unlike Luhman 16A.
“Like Earth and Venus, these objects are twins with very different weather,” said Julien Girard of the Space Telescope Science Institute in Baltimore, Maryland, a member of the discovery team. “It can rain things like silicates or ammonia. It’s pretty awful weather, actually.”
The researchers used an instrument on the Very Large Telescope in Chile to study polarized light from the Luhman 16 system. Polarization is a property of light that represents the direction that the light wave oscillates. Polarized sunglasses block out one direction of polarization to reduce glare and improve contrast.
“Instead of trying to block out that glare, we’re trying to measure it,” explained lead author Max Millar-Blanchaer of the California Institute of Technology (Caltech) in Pasadena, California.
When light is reflected off of particles, such as cloud droplets, it can favor a certain angle of polarization. By measuring the preferred polarization of light from a distant system, astronomers can deduce the presence of clouds without directly resolving either brown dwarf’s cloud structure.
“Even from light-years away, we can use polarization to determine what the light encountered along its path,” added Girard.
“To determine what the light encountered on its way we compared observations against models with different properties: brown dwarf atmospheres with solid cloud decks, striped cloud bands, and even brown dwarfs that are oblate due to their fast rotation. We found that only models of atmospheres with cloud bands could match our observations of Luhman 16A,” explained Theodora Karalidi of the University of Central Florida in Orlando, Florida, a member of the discovery team.
The polarimetry technique isn’t limited to brown dwarfs. It can also be applied to exoplanets orbiting distant stars. The atmospheres of hot, gas giant exoplanets are similar to those of brown dwarfs. Although measuring a polarization signal from exoplanets will be more challenging, due to their relative faintness and proximity to their star, the information gained from brown dwarfs can potentially inform those future studies.
NASA’s upcoming James Webb Space Telescope would be able to study systems like Luhman 16 to look for signs of brightness variations in infrared light that are indicative of cloud features. NASA’s Wide Field Infrared Survey Telescope (WFIRST) will be equipped with a coronagraph instrument that can conduct polarimetry, and may be able to detect giant exoplanets in reflected light and eventual signs of clouds in their atmospheres.
IMAGE….Astronomers have found evidence for a striped pattern of clouds on the brown dwarf called Luhman 16A, as illustrated here in this artist’s concept. The bands of clouds were inferred using a technique called polarimetry, in which polarized light is measured from an astrophysical object much like polarized sunglasses are used to block out glare. This is the first time that polarimetry has been used to measure cloud patterns on a brown dwarf. The red object in the background is Luhman 16B, the partner brown dwarf to Luhman 16A. Together, this pair is the closest brown dwarf system to Earth at 6.5 light-years away. CREDITS: Caltech/R. Hurt (IPAC)
This basically sums it up.
Well, it doesn’t show the other things stars can be after their deaths. But it was a nice video :)
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I love that
After my Life of Stars series I’ve been wanting to do one on galaxies. Maybe I will hmmmmm
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Galaxies: Types and morphology
A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. Galaxies range in size from dwarfs with just a few hundred million (108) stars to giants with one hundred trillion (1014) stars, each orbiting its galaxy’s center of mass.
Galaxies come in three main types: ellipticals, spirals, and irregulars. A slightly more extensive description of galaxy types based on their appearance is given by the Hubble sequence.
Since the Hubble sequence is entirely based upon visual morphological type (shape), it may miss certain important characteristics of galaxies such as star formation rate in starburst galaxies and activity in the cores of active galaxies.
Ellipticals
The Hubble classification system rates elliptical galaxies on the basis of their ellipticity, ranging from E0, being nearly spherical, up to E7, which is highly elongated. These galaxies have an ellipsoidal profile, giving them an elliptical appearance regardless of the viewing angle. Their appearance shows little structure and they typically have relatively little interstellar matter. Consequently, these galaxies also have a low portion of open clusters and a reduced rate of new star formation. Instead they are dominated by generally older, more evolved stars that are orbiting the common center of gravity in random directions.
Spirals
Spiral galaxies resemble spiraling pinwheels. Though the stars and other visible material contained in such a galaxy lie mostly on a plane, the majority of mass in spiral galaxies exists in a roughly spherical halo of dark matter that extends beyond the visible component, as demonstrated by the universal rotation curve concept.
Spiral galaxies consist of a rotating disk of stars and interstellar medium, along with a central bulge of generally older stars. Extending outward from the bulge are relatively bright arms. In the Hubble classification scheme, spiral galaxies are listed as type S, followed by a letter (a, b, or c) that indicates the degree of tightness of the spiral arms and the size of the central bulge.
Barred spiral galaxy
A majority of spiral galaxies, including our own Milky Way galaxy, have a linear, bar-shaped band of stars that extends outward to either side of the core, then merges into the spiral arm structure. In the Hubble classification scheme, these are designated by an SB, followed by a lower-case letter (a, b or c) that indicates the form of the spiral arms (in the same manner as the categorization of normal spiral galaxies).
Ring galaxy
A ring galaxy is a galaxy with a circle-like appearance. Hoag’s Object, discovered by Art Hoag in 1950, is an example of a ring galaxy. The ring contains many massive, relatively young blue stars, which are extremely bright. The central region contains relatively little luminous matter. Some astronomers believe that ring galaxies are formed when a smaller galaxy passes through the center of a larger galaxy. Because most of a galaxy consists of empty space, this “collision” rarely results in any actual collisions between stars.
Lenticular galaxy
A lenticular galaxy (denoted S0) is a type of galaxy intermediate between an elliptical (denoted E) and a spiral galaxy in galaxy morphological classification schemes. They contain large-scale discs but they do not have large-scale spiral arms. Lenticular galaxies are disc galaxies that have used up or lost most of their interstellar matter and therefore have very little ongoing star formation. They may, however, retain significant dust in their disks.
Irregular galaxy
An irregular galaxy is a galaxy that does not have a distinct regular shape, unlike a spiral or an elliptical galaxy. Irregular galaxies do not fall into any of the regular classes of the Hubble sequence, and they are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure.
Dwarf galaxy
Despite the prominence of large elliptical and spiral galaxies, most galaxies in the Universe are dwarf galaxies. These galaxies are relatively small when compared with other galactic formations, being about one hundredth the size of the Milky Way, containing only a few billion stars. Ultra-compact dwarf galaxies have recently been discovered that are only 100 parsecs across.
Interacting
Interactions between galaxies are relatively frequent, and they can play an important role in galactic evolution. Near misses between galaxies result in warping distortions due to tidal interactions, and may cause some exchange of gas and dust. Collisions occur when two galaxies pass directly through each other and have sufficient relative momentum not to merge.
Starburst
Stars are created within galaxies from a reserve of cold gas that forms into giant molecular clouds. Some galaxies have been observed to form stars at an exceptional rate, which is known as a starburst. If they continue to do so, then they would consume their reserve of gas in a time span less than the lifespan of the galaxy. Hence starburst activity usually lasts for only about ten million years, a relatively brief period in the history of a galaxy.
Active galaxy
A portion of the observable galaxies are classified as active galaxies if the galaxy contains an active galactic nucleus (AGN). A significant portion of the total energy output from the galaxy is emitted by the active galactic nucleus, instead of the stars, dust and interstellar medium of the galaxy.
The standard model for an active galactic nucleus is based upon an accretion disc that forms around a supermassive black hole (SMBH) at the core region of the galaxy. The radiation from an active galactic nucleus results from the gravitational energy of matter as it falls toward the black hole from the disc. In about 10% of these galaxies, a diametrically opposed pair of energetic jets ejects particles from the galaxy core at velocities close to the speed of light. The mechanism for producing these jets is not well understood.
The main known types are: Seyfert galaxies, quasars, Blazars, LINERS and Radio galaxy.
source
images: NASA/ESA, Hubble (via wikipedia)
CMB!!!
Aka the cosmic microwave background, which is a huge piece of evidence for the Big Bang Theory of cosmology, a remnant from the early universe.
Also my favorite superhero is Spiderman.
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I am omnipresent
We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard, because that goal will serve to organize and measure the best of our energies and skills, because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one which we intend to win.
John F. Kennedy
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I mean, the song really isn’t accurate.
Also that’s a bit unfair. I’m pretty super that’s a Red Super Giant. Not all stars are that huge xD (even though I’d wouldn’t describe any star as “little”)
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Little star : am I a joke to you?
The rickroll is basically all scientists in a nutshell
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Let’s keep asking questions…
I’m re-watching Crash Course: Astronomy for about the 10 x 10^23 time
Want to join me?
It’s one of my favorites :)
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More nebulae!!!
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M27: Not a Comet : While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things he encountered that were definitely not comets. This is number 27 on his now famous not-a-comet list. In fact, 21st century astronomers would identify it as a planetary nebula, but it’s not a planet either, even though it may appear round and planet-like in a small telescope. Messier 27 (M27) is an excellent example of a gaseous emission nebula created as a sun-like star runs out of nuclear fuel in its core. The nebula forms as the star’s outer layers are expelled into space, with a visible glow generated by atoms excited by the dying star’s intense but invisible ultraviolet light. Known by the popular name of the Dumbbell Nebula, the beautifully symmetric interstellar gas cloud is over 2.5 light-years across and about 1,200 light-years away in the constellation Vulpecula. This impressive color composite highlights details within the well-studied central region and fainter, seldom imaged features in the nebula’s outer halo. It incorporates broad and narrowband images recorded using filters sensitive to emission from hydrogen and oxygen atoms. via NASA
So I actually did the calculations and the surface area of Jupiter could probably fit around 11,474,491,000,000 football fields.
Okay so I googled it and the radius of Jupiter is 43,441 miles. However, I’m going to convert that into meters, which’ll make that radius a cool 69,911,513 m. Next up I’ll plug that into the surface area of a sphere formula (A= 4πr^2) which will get us approximately 6.14 x 10^16 m^2 (or roughly 61,400,000,000,000,000 m^2).
Next, I found the area of one football field to be around 5,351 m^2. Dividing the surface area of Jupiter by the surface area of one football field, we can find out how many football fields will fit onto the surface of Jupiter. And that is 1.1474491 x 10^13. Calculating that, that will be 11,474,491,000,000 football fields (11 trillion or so). Oh boy.
For comparison’s sake, the universe is estimated to have AT MOST 2 trillion galaxies! Which means that Jupiter likely could fit more football fields than the universe has galaxies. Another example, there are an estimated billion trillion stars in the observable universe. Jupiter’s football fields account for half of the stars in our observable universe.
I actually tried to find out how many football fields were in the U.S. for comparison but I still can’t find a statistic.
But also that’s pretty hilarious xD
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No WaY
THE LIFE OF A STAR: STAR NURSERIES
How did this "star stuff" come to exist? The life of stars is a cycle: a star's birth came from a star's death. When it comes to star birth, the star nebulae reigns supreme.
A Nebula (take a look at pictures, they're some of the most beautiful things in the universe) is a giant cloud of dust and gas. This is the region where new stars are formed. Nebulae live in the space in between stars and between galaxies - called interstellar space (or the interstellar medium) - and are often formed by dying stars and supernovas (NASA).
This cloud of particles and gases is mostly made of hydrogen (remember - stars mostly fuse hydrogen!). These appear as patches of light (emission, reflection, or planetary-types) or a dark region against a brighter background (dark-type). This depends on whether "... it reflects light from nearby stars, emits its own light, or re-emits ultraviolet radiation from nearby stars as visible light. If it absorbs light, the nebula appears as a dark patch ..." (The Free Dictionary).
There are four main types of nebulae: emission, reflection, dark, and planetary nebulae.
Emission nebulae are a high-temperature gathering of particles, of which are energized by a nearby ultra-violent-light-emitting star. These particles release radiation as they fall to lower energy states (for more information on electrons moving to energized states and falling back to lower states, read this). This radiation is red because the spectra/wavelength of photons emitted by hydrogen happens to be shifted to the red-end of the visible light spectrum. There are more particles than hydrogen in the nebulae, but hydrogen is the most abundant.
Next up is the reflection nebulae - which reflect the light of nearby stars. As opposed to emission nebulae, reflection are blue, because "the size of the dust grains causes blue light to be reflected more efficiently than red light, so these reflection nebulae frequently appear blue in color ...." The Reddening Law of Nebula describes that the interstellar dust which forms nebulae affects shorter wavelength light more than longer-wavelengths (CalTech).
Then there's the "emo" nebulae: dark nebulae. These are, very simply, nebulae which block light from any nearby sources. The lack of light can cause dark nebulae to be very cold and dark (hence their name), and the heat needed for star formation comes in the form of cosmic rays and gravitational energy as dust gathers. Many stars near dark nebulae emit high levels of infrared light (this type is much more intricate then I've explained, but that summary will do for now. If you're interested in learning more, read this).
Finally, there are planetary nebulae. And these aren't nebulae made of planets. These nebulae are formed when stars (near the ends of their life) throw out a shell of dust. The result is a small, spherical shape, which looks like a planet (hence their name) (METU).
Nebulae themselves are essentially formed by gas and dust particles clumping together by the attractive force of gravity. The clumps increase in density until they form areas where the density is great enough to form massive stars. These massive stars emit ultraviolet radiation, which ionizes surrounding gas and causes photon emissions, allowing us to see nebulae (like we discussed in the types of nebulae). Universe Today said, "Even though the interstellar gas is very dispersed, the amount of matter adds up over the vast distances between the stars. And eventually, and with enough gravitational attraction between clouds, this matter can coalesce and collapse to forms stars and planetary systems."
Britannica notes the structure of nebulae in terms of density and chemical composition: "Various regions exhibit an enormous range of densities and temperatures. Within the Galaxy’s spiral arms about half the mass of the interstellar medium is concentrated in molecular clouds, in which hydrogen occurs in molecular form (H2) and temperatures are as low as 10 kelvins (K). These clouds are inconspicuous optically and are detected principally by their carbon monoxide (CO) emissions in the millimeter wavelength range. Their densities in the regions studied by CO emissions are typically 1,000 H2 molecules per cubic cm. At the other extreme is the gas between the clouds, with a temperature of 10 million K and a density of only 0.001 H+ ion per cubic cm." The composition of nebulae also aligns with what we see with the rest of the universe, mostly being made of hydrogen and the rest being other particles, particularly helium (this matches up with the composition of stars!).
Fun-fact: supernova can create nebulae, but also destroy them. Possibly the most famous nebulae, the "Pillars of Creation," the Eagle Nebula, is hypothesized to have been destroyed by the shockwave of a supernova 6,000 years ago. Since it takes light 7,000 years to travel from that nebulae to the Earth, we won't know for another 1,000 years (Spitzer). If you're wondering how exactly we could know how far nebulae are, check out this article about a new way to measure that distance using the "surface brightness-radius relation", and other distance measurements (such as the parallax measurement).
Now, why did I just explain the intricacies of nebulae in 900 words when this series is supposed to be about stars? Well, when we talk about the birth of a star (and the death sometimes, too), nebulae become important. Take note of what we've discussed in this article: formation, chemical composition, and density. It'll be important in our next chapter (and nuclear fusion, but when is that not important?).
First - Chapter 1: An Introduction
Previous - Chapter 2: Classification
Next - Chapter 4: A Star is Born
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I was researching nebulae for my next article and I wanted to share some images for you guys :)
Nebula are some of the most beautiful things in space. We mostly focused on galaxies and the stars within them, but we forget that in-between galaxies exists the interstellar medium. This is where the nebulae live.
Hope you enjoyed!
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Omg ;D
I love that so much.
Now I really want Magical Girls who represent each stage in a star’s life. Where’s my Magical Girl Neutron Star!?
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concept: team of magical girls who each study a different branch of chemistry at university and their magical powers are based on their branch of study. watch out for physchem, she can do weird quantum shit
Full Moon day!!!
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