Observations from both NASA’s James Webb and Hubble space telescopes created this colorful image of galaxy cluster MACS0416. The colors of different galaxies indicate distances, with bluer galaxies being closer and redder galaxies being more distant or dusty. Some galaxies appear as streaks due to gravitational lensing — a warping effect caused by large masses gravitationally bending the space that light travels through.
While Taylor's Eras Tour explores decades of music, our universe’s eras set the stage for life to exist today. By unraveling cosmic history, scientists can investigate how it happened, from the universe’s origin and evolution to its possible fate.
This infographic outlines the history of the universe.
Scientists aren’t sure what exactly existed at the very beginning of the universe, but they think there wasn’t any normal matter or physics. Things probably didn’t behave like we expect them to today.
Artist's interpretation of the beginning of the universe, with representations of the early cosmos and its expansion.
When the universe debuted, it almost immediately became unstable. Space expanded faster than the speed of light during a very brief period known as inflation. Scientists are still exploring what drove this exponential expansion.
When inflation ended, the universe continued to expand, but much slower. All the energy that previously drove the rapid expansion went into light and matter — normal stuff! Small subatomic particles — protons, neutrons, and electrons — now floated around, though the universe was too hot for them to combine and form atoms.
The particles gravitated together, especially in clumpy spots. The push and pull between gravity and the particles’ inability to stick together created oscillations, or sound waves.
Artist's interpretation of protons and neutrons colliding to form ionized deuterium — a hydrogen isotope with one proton and one neutron — and ionized helium — two protons and two neutrons.
After about three minutes, the universe had expanded and cooled enough for protons and neutrons to stick together. This created the very first elements: hydrogen, helium, and very small amounts of lithium and beryllium.
But it was still too hot for electrons to combine with the protons and neutrons. These free electrons floated around in a hot foggy soup that scattered light and made the universe appear dark.
This animated artist’s concept begins by showing ionized atoms (red blobs), free electrons (green blobs), and photons of light (blue flashes). The ionized atoms scattered light until neutral atoms (shown as brown blobs) formed, clearing the way for light to travel farther through space.
As the universe expanded and cooled further, electrons joined atoms and made them neutral. With the electron plasma out of the way, some light could travel much farther.
An image of the cosmic microwave background (CMB) across the entire sky, taken by ESA's (European Space Agency) Planck space telescope. The CMB is the oldest light we can observe in the universe. Frozen sound waves are visible as miniscule fluctuations in temperature, shown through blue (colder) and red (warmer) coloring.
As neutral atoms formed, the sound waves created by the push and pull between subatomic particles stopped. The waves froze, leaving ripples that were slightly denser than their surroundings. The excess matter attracted even more matter, both normal and “dark.” Dark matter has gravitational influence on its surroundings but is invisible and does not interact with light.
This animation illustrates the absorption of photons — light particles — by neutral hydrogen atoms.
Other than the cosmic microwave background, there wasn't much light during this era since stars hadn’t formed yet. And what light there was usually didn't make it very far since neutral hydrogen atoms are really good at absorbing light. This kicked off an era known as the cosmic dark ages.
This animation illustrates the beginning of star formation as gas begins to clump due to gravity. These protostars heat up as material compresses inside them and throw off material at high speeds, creating shockwaves shown here as expanding rings of light.
Over time, denser areas pulled in more and more matter, in some places becoming so heavy it triggered a collapse. When the matter fell inward, it became hot enough for nuclear fusion to start, marking the birth of the first stars!
A simulation of dark matter forming structure due to gravity.
As the universe expanded, the frozen sound waves created earlier — which now included stars, gas, dust, and more elements produced by stars — stretched and continued attracting more mass. Pulling material together eventually formed the first galaxies, galaxy clusters, and wide-scale, web-like structure.
In this animation, ultraviolet light from stars ionizes hydrogen atoms by breaking off their electrons. Regions already ionized are blue and translucent, areas undergoing ionization are red and white, and regions of neutral gas are dark and opaque.
The first stars were massive and hot, meaning they burned their fuel supplies quickly and lived short lives. However, they gave off energetic ultraviolet light that helped break apart the neutral hydrogen around the stars and allowed light to travel farther.
Animation showing a graph of the universe’s expansion over time. While cosmic expansion slowed following the end of inflation, it began picking up the pace around 5 billion years ago. Scientists still aren't sure why.
By studying the universe’s expansion rate over time, scientists made the shocking discovery that it’s speeding up. They had thought eventually gravity should cause the matter to attract itself and slow down expansion. Some mysterious pressure, dubbed dark energy, seems to be accelerating cosmic expansion. About 10 billion years into the universe’s story, dark energy – whatever it may be – became dominant over matter.
An image of Earth rising in the Moon’s sky. Nicknamed “Earthrise,” Apollo 8 astronauts saw this sight during the first crewed mission to the Moon.
We owe our universe today to each of its unique stages. However, scientists still have many questions about these eras.
Our upcoming Nancy Grace Roman Space Telescope will look back in time to explore cosmic mysteries like dark energy and dark matter – two poorly understood aspects of the universe that govern its evolution and ultimate fate.
Make sure to follow us on Tumblr for your regular dose of space!
Black holes are some of the most bizarre and fascinating objects in the cosmos. Astronomers want to study lots of them, but there’s one big problem – black holes are invisible! Since they don’t emit any light, it’s pretty tough to find them lurking in the inky void of space. Fortunately there are a few different ways we can “see” black holes indirectly by watching how they affect their surroundings.
If you’ve spent some time stargazing, you know what a calm, peaceful place our universe can be. But did you know that a monster is hiding right in the heart of our Milky Way galaxy? Astronomers noticed stars zipping superfast around something we can’t see at the center of the galaxy, about 10 million miles per hour! The stars must be circling a supermassive black hole. No other object would have strong enough gravity to keep them from flying off into space.
Two astrophysicists won half of the Nobel Prize in Physics last year for revealing this dark secret. The black hole is truly monstrous, weighing about four million times as much as our Sun! And it seems our home galaxy is no exception – our Hubble Space Telescope has revealed that the hubs of most galaxies contain supermassive black holes.
Technology has advanced enough that we’ve been able to spot one of these supermassive black holes in a nearby galaxy. In 2019, astronomers took the first-ever picture of a black hole in a galaxy called M87, which is about 55 million light-years away. They used an international network of radio telescopes called the Event Horizon Telescope.
In the image, we can see some light from hot gas surrounding a dark shape. While we still can’t see the black hole itself, we can see the “shadow” it casts on the bright backdrop.
Black holes can come in a smaller variety, too. When a massive star runs out of the fuel it uses to shine, it collapses in on itself. These lightweight or “stellar-mass” black holes are only about 5-20 times as massive as the Sun. They’re scattered throughout the galaxy in the same places where we find stars, since that’s how they began their lives. Some of them started out with a companion star, and so far that’s been our best clue to find them.
Some black holes steal material from their companion star. As the material falls onto the black hole, it gets superhot and lights up in X-rays. The first confirmed black hole astronomers discovered, called Cygnus X-1, was found this way.
If a star comes too close to a supermassive black hole, the effect is even more dramatic! Instead of just siphoning material from the star like a smaller black hole would do, a supermassive black hole will completely tear the star apart into a stream of gas. This is called a tidal disruption event.
But what if two companion stars both turn into black holes? They may eventually collide with each other to form a larger black hole, sending ripples through space-time – the fabric of the cosmos!
These ripples, called gravitational waves, travel across space at the speed of light. The waves that reach us are extremely weak because space-time is really stiff.
Three scientists received the 2017 Nobel Prize in Physics for using LIGO to observe gravitational waves that were sent out from colliding stellar-mass black holes. Though gravitational waves are hard to detect, they offer a way to find black holes without having to see any light.
We’re teaming up with the European Space Agency for a mission called LISA, which stands for Laser Interferometer Space Antenna. When it launches in the 2030s, it will detect gravitational waves from merging supermassive black holes – a likely sign of colliding galaxies!
So we have a few ways to find black holes by seeing stuff that’s close to them. But astronomers think there could be 100 million black holes roaming the galaxy solo. Fortunately, our Nancy Grace Roman Space Telescope will provide a way to “see” these isolated black holes, too.
Roman will find solitary black holes when they pass in front of more distant stars from our vantage point. The black hole’s gravity will warp the starlight in ways that reveal its presence. In some cases we can figure out a black hole’s mass and distance this way, and even estimate how fast it’s moving through the galaxy.
For more about black holes, check out these Tumblr posts!
⚫ Gobble Up These Black (Hole) Friday Deals!
⚫ Hubble’s 5 Weirdest Black Hole Discoveries
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
Dr. Yolanda Shea is a climate scientist at NASA's Langley Research Center. She’s the project scientist for the CLARREO Pathfinder (CPF) mission, which is an instrument that will launch to the International Space Station to measure sunlight reflected from Earth. It will help us understand how much heat is being trapped by our planet’s atmosphere. Her mission is designed to help us get a clearer picture than we currently have of the Earth’s system and how it is changing
Yolanda took time from studying our home planet to answer questions about her life and career! Get to know this Earth scientist:
Starting in early middle school I became interested in the explanations behind the weather maps and satellite images shown on TV. I liked how the meteorologists talked about the temperature, moisture, and winds at different heights in the atmosphere, and then put that together to form the story of our weather forecasts. This made me want to learn more about Earth science, so I went to college to explore this interest more.
The summer after my junior year of college, I had an internship during which my first assignment was to work with a program that estimated ocean currents from satellite measurements. I was fascinated in the fact that scientists had discovered a way to map ocean currents from space!
Although I had learned about Earth remote sensing in my classes, this was my first taste of working with, and understanding the details of, how we could learn more about different aspects of the physical world from satellite measurements.
This led to my learning about other ways we can learn about Earth from space, and that includes rigorous climate monitoring, which is the area I work in now.
Before I start my workday, I like to take a few minutes to eat breakfast, knit (I’m loving sock knitting right now!), and listen to a podcast or audio book. Each workday really looks different for me, but regardless, most days are a combination of quieter moments that I can use for individual work and more interactive times when I’m interfacing with colleagues and talking about project or science issues. Both types of work are fun in different ways, but I’m glad I have a mixture because all researchers need that combination of deep thinking to wrap our minds around complex problems and also time to tackle those problems with others and work on solving them together.
I’ve always loved sunsets. I find them peaceful and beautiful, and I love how each one is unique. They are also a beautiful reminder of the versatility of reflected light, which I study. Sitting for a moment to appreciate the beauty and calm I feel during a sunset helps me feel connected to Earth.
CLARREO Pathfinder (CPF) includes an instrument that will take measurements from the International Space Station and will measure reflected sunlight from Earth. One of its goals is to demonstrate that it can take measurements with high enough accuracy so that, if we have such measurements over long periods of time, like several decades, we could detect changes in Earth’s climate system. The CPF instrument will do this with higher accuracy than previous satellite instruments we’ve designed, and these measurements can be used to improve the accuracy of other satellite instruments.
The longer I work in climate science and learn from the data about how humans have impacted our planet, the more I appreciate the fragility of our one and only home, and the more I want to take care of it.
It’s ok to not have everything figured out at every step of your career journey. Work hard, do your best, and enjoy the journey as it unfolds. You’ll inevitably have some surprises along the way, and regardless of whether they are welcome or not, you’re guaranteed to learn something.
I see jigsaw puzzles as a good illustration of how different members of a science community play a diverse set of roles to work through different problems. Each member is often working on their own image within the greater puzzle, and although it might take them years of work to see their part of the picture come together, each image in the greater puzzle is essential to completing the whole thing. During my career, I’ll work on a section of the puzzle, and I hope to connect my section to others nearby, but we may not finish the whole puzzle. That’s ok, however, because we’ll hand over the work that we’ve accomplished to the next generation of scientists, and they will keep working to bring the picture to light. This is how I try to think about my role in climate science – I hope to contribute to the field in some way; the best thing about what I have done and what I will do, is that someone else will be able to build on my work and keep helping humanity come to a better understanding of our Earth system.
Time and project management skills – I think students tend to learn these skills more organically from their parents and teachers, but in my experience I stumbled along and learned these skills through trial and error. To successfully balance all the different projects that I support now, I have to be organized and disciplined, and I need to have clear plans mapped out, so I have some idea of what’s coming and where my attention needs to be focused.
Another course not specifically related to my field is personal financial management. I was interested in personal finance, and that helped me to seek out information (mainly through various blogs) about how to be responsible with my home finances. There is a lot of information out there, but making sure that students have a solid foundation and know what questions to ask early on will set them to for success (and hopefully fewer mistakes) later on.
I think an interesting part of being an atmospheric scientist and a known sky-watcher is that I get to notice beautiful moments in the sky. I remember being on a trip with friends and I looked up (as I usually do), and I was gifted with a gorgeous sundog and halo arc. It was such a beautiful moment, and because I noticed it, my friends got to enjoy it too.
I absolutely loved being on the PBS Kids TV Show, SciGirls for their episode SkyGirls! This featured a NASA program called Students’ Clouds Observations On-Line (S’COOL). It was a citizen science program where students from around the globe could take observations of clouds from the ground that coincided with satellite overpasses, and the intention was to help scientists validate (or check) the accuracy of the code they use to detect clouds from satellite measurements. I grew up watching educational programming from PBS, so it was an honor to be a science mentor on a TV show that I knew would reach children across the nation who might be interested in different STEM fields. In this photo, the three young women I worked with on the show and I are talking about the different types of clouds.
To stay up to date on Yolanda's mission and everything going on in NASA Earth science, be sure to follow NASA Earth on Twitter and Facebook.
🌎 If you're looking for Earth Day plans, we have live events, Q&As, scavenger hunts and more going on through April 24. Get the details and register for our events HERE.
Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.
sillygirlcarmen Friday Feels “12:22″ 15 minute mix
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Here are all of the Routledge Grammar PDFs that I currently have. I’ll be updating whenever I find more. Let me know if there’s one in particular you want me to look for^^
Last Update: 2017/04/24
Fixed Intermediate Japanese: A Grammar and Workbook link
Added books for Czech, English, French, French Creoles, Persian, Ukranian
Added more books in Cantonese, Danish, Greek, Polish, Spanish, Swedish
Arabic
Arabic: An Essential Grammar Basic Arabic: A Grammar and Workbook Modern Written Arabic: A Comprehensive Grammar
Cantonese
Basic Cantonese: A Grammar and Workbook Cantonese: A Comprehensive Grammar Intermediate Cantonese: A Grammar and Workbook
Czech
Czech: An Essential Grammar
Danish
Danish: A Comprehensive Grammar Danish: An Essential Grammar
Dutch
Basic Dutch: A Grammar and Workbook Dutch: A Comprehensive Grammar Dutch: An Essential Grammar Intermediate Dutch: A Grammar and Workbook
English
English: An Essential Grammar
Finnish
Finnish: An Essential Grammar
French
Modern French Grammar Workbook
French Creoles
French Creoles: A Comprehensive and Comparative Grammar
German
Basic German: A Grammar and Workbook German: An Essential Grammar Intermediate German: A Grammar and Workbook
Greek
Greek: A Comprehensive Grammar Greek: An Essential Grammar of the Modern Language
Hindi
Hindi: An Essential Grammar
Hebrew
Modern Hebrew: An Essential Grammar
Hungarian
Hungarian: An Essential Grammar
Indonesian
Indonesian: A Comprehensive Grammar
Irish
Basic Irish: A Grammar and Workbook Intermediate Irish: A Grammar and Workbook
Italian
Basic Italian: A Grammar and Workbook
Japanese
Basic Japanese: A Grammar and Workbook Intermediate Japanese: A Grammar and Workbook Japanese: A Comprehensive Grammar
Korean
Basic Korean: A Grammar and Workbook Intermediate Korean: A Grammar and Workbook Korean: A Comprehensive Grammar
Latin
Intensive Basic Latin: A Grammar and Workbook Intensive Intermediate Latin: A Grammar and Workbook
Latvian
Latvian: An Essential Grammar
Mandarin Chinese
Basic Chinese: A Grammar and Workbook Intermediate Chinese: A Grammar and Workbook Chinese: A Comprehensive Grammar Chinese: An Essential Grammar
Norwegian
Norwegian: An Essential Grammar
Persian
Basic Persian: A Grammar and Workbook Intermediate Persian: A Grammar and Workbook
Polish
Basic Polish: A Grammar and Workbook Intermediate Polish: A Grammar and Workbook Polish: A Comprehensive Grammar Polish: An Essential Grammar
Portuguese
Portuguese: An Essential Grammar
Romanian
Romanian: An Essential Grammar
Russian
Basic Russian: A Grammar and Workbook Intermediate Russian: A Grammar and Workbook
Serbian
Serbian: An Essential Grammar
Spanish
Basic Spanish: A Grammar and Workbook Intermediate Spanish: A Grammar and Workbook Spanish: An Essential Grammar
Swahili
Swahili Grammar and Workbook
Swedish
Swedish: A Comprehensive Grammar Swedish: An Essential Grammar
Thai
Thai: An Essential Grammar
Turkish
Turkish: A Comprehensive Grammar
Ukrainian
Ukrainian: A Comprehensive Grammar
Urdu
Urdu: An Essential Grammar
Welsh
Modern Welsh: A Comprehensive Grammar
Yiddish
Basic Yiddish: A Grammar and Textbook
Hope this helps everyone out a bit! Happy studying^^
-koreanbreeze
Need study tips? Are you struggling to keep up in class? When you study you don't feel you learn much or anything at all? Getting better grades? Being more prepared than others?
Well. Me too.
So I did these things.
1- SING OUT LOUND! No, Wait! My brother does that. It's Read Out Loud
Be YOUR OWN TEACHER. Why? Good question, perhaps one of the reason can be MY TEACHER LEAVES THINGS OUT.
- Speaking the content out loud helps you to understand it better. Reciting out the words in YOUR OWN WORDS helps a lot. You learn aspects and even learn it far better than when you read a book. - When you speak the lesson or chapter out loud you are processing it as you speak. Think of it like you are giving a speech. Don't you want your speech to be as effective as possible? And how do you make it so effective? By getting authentic information of course!
Make flash notes. The best time to make them is as soon as a new chapter starts. If you are an Edexcel or Cambridge student, I'm sure you will understand just how important the specification is. Even the books has topics at the start of every chapter.
Use each point to make relevant notes on the specifications, this way you can easily know which main points of the topic if stated. Making these flash notes also help you revise and learn as you make them.
Let me know if you wish to know how to best make Flash Notes.
I will make sure to use an example and help you make them as well as link sites to help you better.
Hold it! Stop! Don't hit that back button just yet. This is annoying. So annoying but so desperately needed. You can't get good at Math with doing only one question a day. You need to practice, practice and practice. Study the concept, the method, relevant keywords. Know it so well you can dream of them and write them in your sleep. YOU NEED IT.
Math - those one-page questions need to be practiced at least 3-4 times until you learn it well enough. It seems like a lot of effort, and at times too much to handle and Math is like that but from a person with experience, doing just one question a day can take you up the ladder of improvement. Physics - questions need a to be revised and checked, especially those that voice out the same question. The question maybe same but they may have a different method of getting the answer. Chemistry - REVISE THE EQUATIONS. Think of the equations as the key aspect to breathing. One single thing wrong you lose a mark. AND EVERY MARK COUNTS. Biology - KEY TERMS. Key terms are so important, you have no idea. You cannot go in a Biology exam without those terms. At times the teachers won't even tell you those terms, So, those terms are so important you have no idea.
If you want to understand this better, do let me know. I will do my best to help you understand it better.
Once while doing a paper I was quite confident I would pass, until I got my paper back. Not only was my score low, but it was low due to certain answers not accepted by the paper. How come? They were the same points my teacher had told me about. Everything she taught, then why the low grade? Simple, because she never mentioned the answers that will be accepted in the paper. Some of the answers were never taught in class. Often times teachers do not mention certain points that are relevant to the papers and so students lose marks.
By attempting the papers, you understand what the examiner is looking for and how to best attempt the questions.
Tip: Pay attention to the reject part of the marking scheme. They help you understand the paper pattern and how best to assess the paper.
When you see that one question with at least 6-7 or 10-12 marks. NOTE THEM DOWN. Why? Simple they aid you when you need them most. Best example I have for you if the most recent one I did.
When studying for Chemistry Unit 5, those questions with even 5 marks that seem really important and you have not done in class before, have them in a note book. This lets you know what can and will come in the paper and how you must asset them.
Say that question where you must find the sides of the shape in Math. Trigonometry questions, find base from plane, those find the “X” question and many more. If you cannot solve them or have trouble solving them and are taking a long time. NOTE THEM DOWN.
Have it in a notebook, with question and answer. Make it so when you come to revise later you can understand and figure out a way to gain those marks more easily.
I hope all this helps.
The Secretary-General's son Gabriel Lougou Unicef.org 🇺🇳🇨🇫🇩🇰.
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