Starry Greetings!

🖤🖤🖤

“There are people who are always in love with the sky, no matter the weather. One day you will find someone who’ll love you the same way.”

Just let Earth enjoy the theory of general relativity, Mars.

P.S. Today (in 1905) the theory of special relativity was revealed!

Melotte 15, Inside the Heart

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)

Starry Greetings!

Seems like Planet X wanted to finish off Halloween with one… last…story…

https://cosmosmagazine.com/physics/vacuum-decay-ultimate-catastrophe

https://www.youtube.com/watch?v=ijFm6DxNVyI

http://io9.gizmodo.com/we-might-be-destroying-the-universe-just-by-looking-at-1514652112

This mosaic image from the NASA/ESA/ASI Cassini-Huygens spacecraft is centered at 9 degrees north latitude, 254 degrees west longitude. The image was acquired at a distance of about 57,800 km from Rhea.

Image credit: NASA/JPL

OSIRIS-REx arrived at asteroid Bennu this week! It will stay in orbit to do a complete survey of the asteroid. But even cooler, it will get so close to the surface it will touch Bennu briefly and use a puff of hydrogen to dislodge surface material, that it will then collect. After that, OSIRIS-REx heads back to Earth to deliver the sample!

Here is a really cool video on how this little orbiter got to Bennu and detailing its mission.

https://youtu.be/NYGHbl_esgw

NGC 3921, Spirit Galaxy

some memes I made to express my current frustrations with academia feel free to add your own

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