Maybe We Shouldn’t Have Given Pluto Unrealistic Expectations Of Reality. 🤷🏻‍♀️

What is a Wormhole?

Wormholes were first theorized in 1916, though that wasn’t what they were called at the time. While reviewing another physicist’s solution to the equations in Albert Einstein’s theory of general relativity, Austrian physicist Ludwig Flamm realized another solution was possible. He described a “white hole,” a theoretical time reversal of a black hole. Entrances to both black and white holes could be connected by a space-time conduit.

In 1935, Einstein and physicist Nathan Rosen used the theory of general relativity to elaborate on the idea, proposing the existence of “bridges” through space-time. These bridges connect two different points in space-time, theoretically creating a shortcut that could reduce travel time and distance. The shortcuts came to be called Einstein-Rosen bridges, or wormholes.

Certain solutions of general relativity allow for the existence of wormholes where the mouth of each is a black hole. However, a naturally occurring black hole, formed by the collapse of a dying star, does not by itself create a wormhole.

Wormholes are consistent with the general theory of relativity, but whether wormholes actually exist remains to be seen.

A wormhole could connect extremely long distances such as a billion light years or more, short distances such as a few meters, different universes, or different points in time

For a simplified notion of a wormhole, space can be visualized as a two-dimensional (2D) surface. In this case, a wormhole would appear as a hole in that surface, lead into a 3D tube (the inside surface of a cylinder), then re-emerge at another location on the 2D surface with a hole similar to the entrance. An actual wormhole would be analogous to this, but with the spatial dimensions raised by one. For example, instead of circular holes on a 2D plane, the entry and exit points could be visualized as spheres in 3D space.

Science fiction is filled with tales of traveling through wormholes. But the reality of such travel is more complicated, and not just because we’ve yet to spot one.

The first problem is size. Primordial wormholes are predicted to exist on microscopic levels, about 10–33 centimeters. However, as the universe expands, it is possible that some may have been stretched to larger sizes.

Another problem comes from stability. The predicted Einstein-Rosen wormholes would be useless for travel because they collapse quickly.

“You would need some very exotic type of matter in order to stabilize a wormhole,” said Hsu, “and it’s not clear whether such matter exists in the universe.”

But more recent research found that a wormhole containing “exotic” matter could stay open and unchanging for longer periods of time.

Exotic matter, which should not be confused with dark matter or antimatter, contains negative energy density and a large negative pressure. Such matter has only been seen in the behavior of certain vacuum states as part of quantum field theory.

If a wormhole contained sufficient exotic matter, whether naturally occurring or artificially added, it could theoretically be used as a method of sending information or travelers through space. Unfortunately, human journeys through the space tunnels may be challenging.

Wormholes may not only connect two separate regions within the universe, they could also connect two different universes. Similarly, some scientists have conjectured that if one mouth of a wormhole is moved in a specific manner, it could allow for time travel.

Although adding exotic matter to a wormhole might stabilize it to the point that human passengers could travel safely through it, there is still the possibility that the addition of “regular” matter would be sufficient to destabilize the portal.

Today’s technology is insufficient to enlarge or stabilize wormholes, even if they could be found. However, scientists continue to explore the concept as a method of space travel with the hope that technology will eventually be able to utilize them.

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R Leporis: A Vampire’s Star via NASA https://ift.tt/2Rt7kU7

Central Cygnus Skyscape via NASA https://ift.tt/2vgpcsn

Omg I’m dying

my favorite thing about the spanish harry potter translation is that instead of calling voldemort “the dark lord,” they call him señor tenebroso, which basically means “mr. spooky”

I hope that someday, you find an amazing girl. The kind of girl who means everything to you and makes you want to spend every moment of your time with her. The kind of girl who keeps you up at night, just thinking about her beautiful smile, and when you finally fall asleep, she`s all you dream about. I hope she`s the first thing to cross your mind when you wake up in the morning. I hope she changes you in a way you could never understand, yet you know it`s for the better. I hope she`s the kind of girl you would die for. The kind of girl who could make you cry, even though you`d never admit it. The kind of girl who makes you want to go out and do something special, something that means everything to the both of you. The kind of girl you can have silly fights with, then kiss and make up and hold her in your arms like you`re falling in love all over again. I hope you make memories with her her you never forget. I hope she`s your world, and what you have with her is nothing less than perfection. and I hope that one day, you lose her. I hope you mess up and as hard as you try to keep her there with you, she slips through the cracks of your broken heart. I hope it destroys you, because you realized you`ve lost the person you once called your everything. I hope you see every moment you spent together spin away down the drain like it was waiting to happen. I hope you stay up at night because she`s on your mind and when you fall asleep, she haunts your dreams. I hope her beautiful smile stays pressed in your mind like a scar that won’t fade away. I hope you realize that you`re a new person because of her, I hope your new self feels incomplete without her and you miss the old you. The one that was okay with being alone, because you’d rather be the heartbreaker than the heartbroken.

Your best source of quotes for the broken hearted (via thelovewhisperer)

Interesting facts about stars

Stars are giant, luminous spheres of plasma. There are billions of them — including our own sun — in the Milky Way Galaxy. And there are billions of galaxies in the universe. So far, we have learned that hundreds also have planets orbiting them.

1. Stars are made of the same stuff

All stars begin from clouds of cold molecular hydrogen that gravitationally collapse. As they cloud collapses, it fragments into many pieces that will go on to form individual stars. The material collects into a ball that continues to collapse under its own gravity until it can ignite nuclear fusion at its core. This initial gas was formed during the Big Bang, and is always about 74% hydrogen and 25% helium. Over time, stars convert some of their hydrogen into helium. That’s why our Sun’s ratio is more like 70% hydrogen and 29% helium. But all stars start out with ¾ hydrogen and ¼ helium, with other trace elements.

2. Most stars are red dwarfs

If you could collect all the stars together and put them in piles, the biggest pile, by far, would be the red dwarfs. These are stars with less than 50% the mass of the Sun. Red dwarfs can even be as small as 7.5% the mass of the Sun. Below that point, the star doesn’t have the gravitational pressure to raise the temperature inside its core to begin nuclear fusion. Those are called brown dwarfs, or failed stars. Red dwarfs burn with less than 1/10,000th the energy of the Sun, and can sip away at their fuel for 10 trillion years before running out of hydrogen.

3. Mass = temperature = color

The color of stars can range from red to white to blue. Red is the coolest color; that’s a star with less than 3,500 Kelvin. Stars like our Sun are yellowish white and average around 6,000 Kelvin. The hottest stars are blue, which corresponds to surface temperatures above 12,000 Kelvin. So the temperature and color of a star are connected. Mass defines the temperature of a star. The more mass you have, the larger the star’s core is going to be, and the more nuclear fusion can be done at its core. This means that more energy reaches the surface of the star and increases its temperature. There’s a tricky exception to this: red giants. A typical red giant star can have the mass of our Sun, and would have been a white star all of its life. But as it nears the end of its life it increases in luminosity by a factor of 1000, and so it seems abnormally bright. But a blue giant star is just big, massive and hot.

4. Most stars come in multiples

It might look like all the stars are out there, all by themselves, but many come in pairs. These are binary stars, where two stars orbit a common center of gravity. And there are other systems out there with 3, 4 and even more stars. Just think of the beautiful sunrises you’d experience waking up on a world with 4 stars around it.

5. The biggest stars would engulf Saturn

Speaking of red giants, or in this case, red supergiants, there are some monster stars out there that really make our Sun look small. A familiar red supergiant is the star Betelgeuse in the constellation Orion. It has about 20 times the mass of the Sun, but it’s 1,000 times larger. But that’s nothing. The largest known star is the monster UY Scuti.  It is a current and leading candidate for being the largest known star by radius and is also one of the most luminous of its kind. It has an estimated radius of 1,708 solar radii (1.188×109 kilometres; 7.94 astronomical units); thus a volume nearly 5 billion times that of the Sun.

6. There are many, many stars

Quick, how many stars are there in the Milky Way. You might be surprised to know that there are 200-400 billion stars in our galaxy. Each one is a separate island in space, perhaps with planets, and some may even have life.

7. The Sun is the closest star

Okay, this one you should know, but it’s pretty amazing to think that our own Sun, located a mere 150 million km away is average example of all the stars in the Universe. Our own Sun is classified as a G2 yellow dwarf star in the main sequence phase of its life. The Sun has been happily converting hydrogen into helium at its core for 4.5 billion years, and will likely continue doing so for another 7+ billion years. When the Sun runs out of fuel, it will become a red giant, bloating up many times its current size. As it expands, the Sun will consume Mercury, Venus and probably even Earth. 

8. The biggest stars die early

Small stars like red dwarfs can live for trillions of years. But hypergiant stars, die early, because they burn their fuel quickly and become supernovae. On average, they live only a few tens of millions of years or less.

9. Failed stars

Brown dwarfs are substellar objects that occupy the mass range between the heaviest gas giant planets and the lightest stars, of approximately 13 to 75–80 Jupiter masses (MJ). Below this range are the sub-brown dwarfs, and above it are the lightest red dwarfs (M9 V). Unlike the stars in the main-sequence, brown dwarfs are not massive enough to sustain nuclear fusion of ordinary hydrogen (1H) to helium in their cores.

10. Sirius: The Brightest Star in the Night Sky

Sirius is a star system and the brightest star in the Earth’s night sky. With a visual apparent magnitude of −1.46, it is almost twice as bright as Canopus, the next brightest star. The system has the Bayer designation Alpha Canis Majoris (α CMa). What the naked eye perceives as a single star is a binary star system, consisting of a white main-sequence star of spectral type A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, called Sirius B. 

To know more click the links: white dwarf, supernova, +stars, pulsars

sources: wikipedia and universetoday.com

image credits: NASA/JPL, Morgan Keenan, ESO, Philip Park / CC BY-SA 3.0

StopSmiling: Just to clear the record and get the real story; Was the name of the band really taken from a short story by Virginia Woolf?

Isaac Brock: It was required reading in some class I was taking at the time. It was from a Virginia Woolf book where she referred to people who were working the grind as “modest mouse-like people.” I wanted to originally name the band Modest Mouse-like People, but that seemed a little long. I regretted the name for some time because it sounds so cutesy. I got really sick of seeing posters with Mighty Mouse on them. I don’t even remember which story [“A Mark on the Wall”]. I just remember that part.

These 5 Women Deserved, And Were Unjustly Denied, A Nobel Prize In Physics

“The fact of the matter is that there is no concrete evidence that women are in any way inherently inferior to men when it comes to work in any of the sciences or any of their sub-fields. But there is overwhelming evidence for misogyny, sexism, and institutional bias that hinders their careers and fails to recognize them for their outstanding achievements. When you think of the Nobel Laureates in Physics and wonder why there are so few women, make sure you remember Cecilia Payne, Chien-Shiung Wu, Vera Rubin, Jocelyn Bell-Burnell, and Lise Meitner. The Nobel committee may have forgotten or overlooked their contributions until it was too late, but that doesn’t mean we have to. In all the sciences, we want the best, brightest, most capable, and hardest workers this world has to offer. Looking back on history with accurate eyes only serves to demonstrate how valuable, and yet undervalued, women in science have been.”

In most intellectual lines of work, if you claimed that a certain type of person wasn’t mentally capable of doing as good a job as another, you’d be rightfully called a bigot. Yet somehow, in a myriad of the sciences (such as physics), there are those who simultaneously claim that “women are inferior to men” alongside the claim that it isn’t sexist or bigoted to say so.

But what there is a long history of, in physics, is women being denied their due credit for discoveries and advances that they were an integral part of. Even in the aftermath of last week’s events, when physicist Donna Strickland became just the third woman ever to be awarded a Nobel Prize, many have claimed that she isn’t worthy, for reasons that have never been applied to men.

Well, meet five women you might not be aware of who certainly earned a Nobel Prize, even if they were never awarded one. We cannot rewrite history, but we can right the legacy of its wrongs in our public consciousness.

Orion Launch Abort System Attitude Control Motor Hot-Fire Test via NASA https://ift.tt/2Wk4fYE