The cosmic microwave background (CMB) is electromagnetic radiation as a remnant from an early stage of the universe in Big Bang cosmology. In older literature, the CMB is also variously known as cosmic microwave background radiation (CMBR) or “relic radiation”. The CMB is a faint cosmic background radiation filling all space that is an important source of data on the early universe because it is the oldest electromagnetic radiation in the universe, dating to the epoch of recombination.
With a traditional optical telescope, the space between stars and galaxies (the background) is completely dark. However, a sufficiently sensitive radio telescope shows a faint background noise, or glow, almost isotropic, that is not associated with any star, galaxy, or other object. This glow is strongest in the microwave region of the radio spectrum. The accidental discovery of the CMB in 1964 by American radio astronomers Arno Penzias and Robert Wilson was the culmination of work initiated in the 1940s, and earned the discoverers the 1978 Nobel Prize in Physics.
The discovery of CMB is landmark evidence of the Big Bang origin of the universe. When the universe was young, before the formation of stars and planets, it was denser, much hotter, and filled with a uniform glow from a white-hot fog of hydrogen plasma. As the universe expanded, both the plasma and the radiation filling it grew cooler. When the universe cooled enough, protons and electrons combined to form neutral hydrogen atoms. Unlike the uncombined protons and electrons, these newly conceived atoms could not absorb the thermal radiation, and so the universe became transparent instead of being an opaque fog. Cosmologists refer to the time period when neutral atoms first formed as the recombination epoch, and the event shortly afterwards when photons started to travel freely through space rather than constantly being scattered by electrons and protons in plasma is referred to as photon decoupling.
Basically, cosmic microwave background radiation is the fossil of light, resulting from a time when the Universe was hot and dense, only 380,000 years after the Big Bang.
Cosmic microwave background radiation is an electromagnetic radiation that fills the entire universe, whose spectrum is that of a blackbody at a temperature of 2.725 kelvin.
Cosmic microwave background radiation, along with the spacing from galaxies and the abundance of light elements, is one of the strongest observational evidences of the Big Bang model, which describes the evolution of the universe. Penzias and Wilson received the Nobel Prize in Physics in 1978 for this discovery
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images credit: Image credit: Institute of Astronomy / National Tsing Hua University/ NASA/ESA Hubble, wikipedia
Created using still images taken by the Cassini spacecraft during it’s flyby of Jupiter and while at Saturn. Shown is Io and Europa over Jupiter’s Great Red Spot.
NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill
“I am wondering how there isn’t a center of the universe and how the cosmic background radiation is [equally] far away everywhere we look. It seems to me that when the universe expands… there should be a place where it started expanding.”
Ah, the old center of the Universe question. If the Big Bang happened a long time ago, and we see galaxies moving away from us faster and faster the farther away they are, then where did the Big Bang happen? Where did the expansion start?
It seems like such a simple question, but it turns out this is the wrong question to be asking. The way space and the expanding Universe works is very different from the picture most of us have in our heads, which is much more like an explosion than like an expansion. Yet there’s a very large suite of evidence that points us away from an explosion.
Instead of asking *where* the Big Bang occurred, we should be asking *when* the Big Bang occurred. It makes a lot more sense when you think about it in those terms. Come and find out why.
The Aral Sea was once the fourth-largest lake in the world. Fed primarily by snowmelt and precipitation flowing down from faraway mountains, it was a temperate oasis in an arid region. But in the 1960s, the Soviet Union diverted two major rivers to irrigate farmland, cutting off the inland sea from its source. As the Aral Sea dried up, fisheries collapsed, as did the communities that depended on them. The remaining water supply became increasingly salty and polluted with runoff from agricultural plots. Loss of the Aral Sea’s water influenced regional climate, making the winters even colder and the summers much hotter.
While seasonal rains still bring water to the Aral Sea, the lake is roughly one-tenth of its original size. These satellite images show how the Aral Sea and its surrounding landscape has changed over the past few decades.
For more details about these images, read the full stories here: https://go.nasa.gov/2PqJ1ot
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The role plastic products play in the daily lives of people all over the world is interminable. We could throw statistics at you all day long (e.g. Upwards of 300 MILLION tons of plastic are consumed each year), but the impact of these numbers border on inconceivable.
For those living on the coasts, a mere walk on the beach can give anyone insight into how staggering our addiction to plastic has become as bottles, cans, bags, lids and straws (just to name a few) are ever-present. In other areas that insight is more poignant as the remains of animal carcasses can frequently be observed; the plastic debris that many of them ingested or became entangled in still visible long after their death. Sadly, an overwhelming amount of plastic pollution isn’t even visible to the human eye, with much of the pollution occurring out at sea or on a microscopic level.
The short-lived use of millions of tons of plastic is, quite simply, unsustainable and dangerous. We have only begun to see the far-reaching consequences of plastic pollution and how it affects all living things. According to a study from Plymouth University, plastic pollution affects at least 700 marine species, while some estimates suggest that at least 100 million marine mammals are killed each year from plastic pollution. Here are some of the marine species most deeply impacted by plastic pollution.
Sea Turtles
Seals and Sea Lions
Seabirds
Fish
Whales and Dolphins
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More than ever, the fate of the ocean is in our hands. To be good stewards and leave a thriving ocean for future generations, we need to make changes big and small wherever we are.
Every purchase supports Ocean Conservation. We give a portion of our profits to Organizations that bravely fight for Marine Conservation.
Deep Space Missions
On this day 50 years ago, human beings embarked on a journey to set foot on another world for the very first time.
At 9:32 a.m. EDT, millions watched as Apollo astronauts Neil Armstrong, Buzz Aldrin and Michael Collins lifted off from Launch Pad 39A at the Kennedy Space Center in Cape Canaveral, Florida, flying high on the most powerful rocket ever built: the mighty Saturn V.
As we prepare to return humans to the lunar surface with our Artemis program, we’re planning to make history again with a similarly unprecedented rocket, the Space Launch System (SLS). The SLS will be our first exploration-class vehicle since the Saturn V took American astronauts to the Moon a decade ago. With its superior lift capability, the SLS will expand our reach into the solar system, allowing astronauts aboard our Orion spacecraft to explore multiple, deep-space destinations including near-Earth asteroids, the Moon and ultimately Mars.
So, how does the Saturn V measure up half a century later? Let’s take a look.
Every human who has ever stepped foot on the Moon made it there on a Saturn V rocket. The Saturn rockets were the driving force behind our Apollo program that was designed to land humans on the Moon and return them safely back to Earth.
Developed at our Marshall Space Flight Center in the 1960s, the Saturn V rocket (V for the Roman numeral “5”) launched for the first time uncrewed during the Apollo 4 mission on November 9, 1967. One year later, it lifted off for its first crewed mission during Apollo 8. On this mission, astronauts orbited the Moon but did not land. Then, on July 16, 1969, the Apollo 11 mission was the first Saturn V flight to land astronauts on the Moon. In total, this powerful rocket completed 13 successful missions, landing humans on the lunar surface six times before lifting off for the last time in 1973.
Just as the Saturn V was the rocket of the Apollo generation, the Space Launch System will be the driving force behind a new era of spaceflight: the Artemis generation.
During our Artemis missions, SLS will take humanity farther than ever before. It is the vehicle that will return our astronauts to the Moon by 2024, transporting the first woman and the next man to a destination never before explored – the lunar South Pole. Over time, the rocket will evolve into increasingly more powerful configurations to provide the foundation for human exploration beyond Earth’s orbit to deep space destinations, including Mars.
SLS will take flight for the first time during Artemis 1 where it will travel 280,000 miles from Earth – farther into deep space than any spacecraft built for humans has ever ventured.
The Saturn V was big.
In fact, the Vehicle Assembly Building at Kennedy Space Center is one of the largest buildings in the world by volume and was built specifically for assembling the massive rocket. At a height of 363 feet, the Saturn V rocket was about the size of a 36-story building and 60 feet taller than the Statue of Liberty!
Measured at just 41 feet shy of the Saturn V, the initial SLS rocket will stand at a height of 322 feet. Because this rocket will evolve into heavier lift capacities to facilitate crew and cargo missions beyond Earth’s orbit, its size will evolve as well. When the SLS reaches its maximum lift capability, it will stand at a height of 384 feet, making it the tallest rocket in the world.
For the 1960s, the Saturn V rocket was a beast – to say the least.
Fully fueled for liftoff, the Saturn V weighed 6.2 million pounds and generated 7.6 million pounds of thrust at launch. That is more power than 85 Hoover Dams! This thrust came from five F-1 engines that made up the rocket’s first stage. With this lift capability, the Saturn V had the ability to send 130 tons (about 10 school buses) into low-Earth orbit and about 50 tons (about 4 school buses) to the Moon.
Photo of SLS rocket booster test
Unlike the Saturn V, our SLS rocket will evolve over time into increasingly more powerful versions of itself to accommodate missions to the Moon and then beyond to Mars.
The first SLS vehicle, called Block 1, will weigh 5.75 million pounds and produce 8.8 million pounds of thrust at time of launch. That’s 15 percent more than the Saturn V produced during liftoff! It will also send more than 26 tons beyond the Moon. Powered by a pair of five-segment boosters and four RS-25 engines, the rocket will reach the period of greatest atmospheric force within 90 seconds!
Following Block 1, the SLS will evolve five more times to reach its final stage, Block 2 Cargo. At this stage, the rocket will provide 11.9 million pounds of thrust and will be the workhorse vehicle for sending cargo to the Moon, Mars and other deep space destinations. SLS Block 2 will be designed to lift more than 45 tons to deep space. With its unprecedented power and capabilities, SLS is the only rocket that can send our Orion spacecraft, astronauts and large cargo to the Moon on a single mission.
The Saturn V was designed as a multi-stage system rocket, with three core stages. When one system ran out of fuel, it separated from the spacecraft and the next stage took over. The first stage, which was the most powerful, lifted the rocket off of Earth’s surface to an altitude of 68 kilometers (42 miles). This took only 2 minutes and 47 seconds! The first stage separated, allowing the second stage to fire and carry the rest of the stack almost into orbit. The third stage placed the Apollo spacecraft and service module into Earth orbit and pushed it toward the Moon. After the first two stages separated, they fell into the ocean for recovery. The third stage either stayed in space or crashed into the Moon.
Much like the Saturn V, our Space Launch System is also a multi-stage rocket. Its three stages (the solid rocket boosters, core stage and upper stage) will each take turns thrusting the spacecraft on its trajectory and separating after each individual stage has exhausted its fuel. In later, more powerful versions of the SLS, the third stage will carry both the Orion crew module and a deep space habitat module.
Just as the Saturn V and Apollo era signified a new age of exploration and technological advancements, the Space Launch System and Artemis missions will bring the United States into a new age of space travel and scientific discovery.
Join us in celebrating the 50th anniversary of the Apollo 11 Moon landing and hear about our future plans to go forward to the Moon and on to Mars by tuning in to a special two-hour live NASA Television broadcast at 1 p.m. ET on Friday, July 19. Watch the program at www.nasa.gov/live.
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http://www.sci-news.com/astronomy/chandra-extremely-long-cosmic-jet-early-universe-09436.html
When Neil Armstrong took his first steps on the Moon 50 years ago, he famously said “that’s one small step for a man, one giant leap for mankind.” He was referring to the historic milestone of exploring beyond our own planet — but there’s also another way to think about that giant leap: the massive effort to develop technologies to safely reach, walk on the Moon and return home led to countless innovations that have improved life on Earth.
Armstrong took one small step on the lunar surface, but the Moon landing led to a giant leap forward in innovations for humanity.
Here are five examples of technology developed for the Apollo program that we’re still using today:
As soon as we started planning to send astronauts into space, we faced the problem of what to feed them — and how to ensure the food was safe to eat. Can you imagine getting food poisoning on a spacecraft, hundreds of thousands of miles from home?
We teamed up with a familiar name in food production: the Pillsbury Company. The company soon realized that existing quality control methods were lacking. There was no way to be certain, without extensive testing that destroyed the sample, that the food was free of bacteria and toxins.
Pillsbury revamped its entire food-safety process, creating what became the Hazard Analysis and Critical Control Point system. Its aim was to prevent food safety problems from occurring, rather than catch them after the fact. They managed this by analyzing and controlling every link in the chain, from the raw materials to the processing equipment to the people handling the food.
Today, this is one of the space program’s most far-reaching spinoffs. Beyond keeping the astronaut food supply safe, the Hazard Analysis and Critical Point system has also been adopted around the world — and likely reduced the risk of bacteria and toxins in your local grocery store.
The Apollo spacecraft was revolutionary for many reasons. Did you know it was the first vehicle to be controlled by a digital computer? Instead of pushrods and cables that pilots manually adjusted to manipulate the spacecraft, Apollo’s computer sent signals to actuators at the flick of a switch.
Besides being physically lighter and less cumbersome, the switch to a digital control system enabled storing large quantities of data and programming maneuvers with complex software.
Before Apollo, there were no digital computers to control airplanes either. Working together with the Navy and Draper Laboratory, we adapted the Apollo digital flight computer to work on airplanes. Today, whatever airline you might be flying, the pilot is controlling it digitally, based on the technology first developed for the flight to the Moon.
A shock absorber descended from Apollo-era dampers and computers saves lives by stabilizing buildings during earthquakes.
Apollo’s Saturn V rockets had to stay connected to the fueling tubes on the launchpad up to the very last second. That presented a challenge: how to safely move those tubes out of the way once liftoff began. Given how fast they were moving, how could we ensure they wouldn’t bounce back and smash into the vehicle?
We contracted with Taylor Devices, Inc. to develop dampers to cushion the shock, forcing the company to push conventional shock isolation technology to the limit.
Shortly after, we went back to the company for a hydraulics-based high-speed computer. For that challenge, the company came up with fluidic dampers—filled with compressible fluid—that worked even better. We later applied the same technology on the Space Shuttle’s launchpad.
The company has since adapted these fluidic dampers for buildings and bridges to help them survive earthquakes. Today, they are successfully protecting structures in some of the most quake-prone areas of the world, including Tokyo, San Francisco and Taiwan.
We’ve all seen runners draped in silvery “space blankets” at the end of marathons, but did you know the material, called radiant barrier insulation, was actually created for space?
Temperatures outside of Earth’s atmosphere can fluctuate widely, from hundreds of degrees below to hundreds above zero. To better protect our astronauts, during the Apollo program we invented a new kind of effective, lightweight insulation.
We developed a method of coating mylar with a thin layer of vaporized metal particles. The resulting material had the look and weight of thin cellophane packaging, but was extremely reflective—and pound-for-pound, better than anything else available.
Today the material is still used to protect astronauts, as well as sensitive electronics, in nearly all of our missions. But it has also found countless uses on the ground, from space blankets for athletes to energy-saving insulation for buildings. It also protects essential components of MRI machines used in medicine and much, much more.
Image courtesy of the U.S. Marines
Patients in hospitals are hooked up to sensors that send important health data to the nurse’s station and beyond — which means when an alarm goes off, the right people come running to help.
This technology saves lives every day. But before it reached the ICU, it was invented for something even more extraordinary: sending health data from space down to Earth.
When the Apollo astronauts flew to the Moon, they were hooked up to a system of sensors that sent real-time information on their blood pressure, body temperature, heart rate and more to a team on the ground.
The system was developed for us by Spacelabs Healthcare, which quickly adapted it for hospital monitoring. The company now has telemetric monitoring equipment in nearly every hospital around the world, and it is expanding further, so at-risk patients and their doctors can keep track of their health even outside the hospital.
Only a few people have ever walked on the Moon, but the benefits of the Apollo program for the rest of us continue to ripple widely.
In the years since, we have continued to create innovations that have saved lives, helped the environment, and advanced all kinds of technology.
Now we’re going forward to the Moon with the Artemis program and on to Mars — and building ever more cutting-edge technologies to get us there. As with the many spinoffs from the Apollo era, these innovations will transform our lives for generations to come.
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