Our James Webb Space Telescope is an epic mission that will give us a window into the early universe, allowing us to see the time period during which the first stars and galaxies formed. Webb will not only change what we know, but also how we think about the night sky and our place in the cosmos. Want to learn more? Join two of our scientists as they talk about what the James Webb Telescope is, why it is being built and what it will help us learn about the universe…
First, meet Dr. Amber Straughn. She grew up in a small farming town in Arkansas, where her fascination with astronomy began under beautifully dark, rural skies. After finishing a PhD in Physics, she came to NASA Goddard to study galaxies using data from our Hubble Space Telescope. In addition to research, Amber's role with the Webb project’s science team involves working with Communications and Outreach activities. She is looking forward to using data from Webb in her research on galaxy formation and evolution.
We also talked with Dr. John Mather, the Senior Project Scientist for Webb, who leads our science team. He won a Nobel Prize in 2006 for confirming the Big Bang theory with extreme precision via a mission called the Cosmic Background Explorer (COBE) mission. John was the Principal Investigator (PI) of the Far IR Absolute Spectrophotometer (FIRAS) instrument on COBE. He’s an expert on cosmology, and infrared astronomy and instrumentation.
Dr. Amber Straughn: The James Webb Space Telescope at its core is designed to answer some of the biggest questions we have in astronomy today. And these are questions that go beyond just being science questions; they are questions that really get to the heart of who we are as human beings; questions like where do we come from? How did we get here? And, of course, the big one – are we alone?
To answer the biggest questions in astronomy today we really need a very big telescope. And the James Webb Space Telescope is the biggest telescope we’ve ever attempted to send into space. It sets us up with some really big engineering challenges.
Dr. John Mather: One of the wonderful challenges about astronomy is that we have to imagine something so we can go look for it. But nature has a way of being even more creative than we are, so we have always been surprised by what we see in the sky. That’s why building a telescope has always been interesting. Every time we build a better one, we see something we never imagined was out there. That’s been going on for centuries. This is the next step in that great series, of bigger and better and more powerful telescopes that surely will surprise us in some way that I can’t tell you.
It has never been done before, building a big telescope that will unfold in space. We knew we needed something that was bigger than the rocket to achieve the scientific discoveries that we wanted to make. We had to invent a new way to make the mirrors, a way to focus it out in outer space, several new kinds of infrared detectors, and we had to invent the big unfolding umbrella we call the sunshield.
Amber: One of Webb’s goals is to detect the very first stars and galaxies that were born in the very early universe. This is a part of the universe that we haven’t seen at all yet. We don’t know what’s there, so the telescope in a sense is going to open up this brand-new part of the universe, the part of the universe that got everything started.
John: The first stars and galaxies are really the big mystery for us. We don’t know how that happened. We don’t know when it happened. We don’t know what those stars were like. We have a pretty good idea that they were very much larger than the sun and that they would burn out in a tremendous burst of glory in just a few million years.
Amber: We also want to watch how galaxies grow and change over time. We have questions like how galaxies merge, how black holes form and how gas inflows and outflows affect galaxy evolution. But we’re really missing a key piece of the puzzle, which is how galaxies got their start.
John: Astronomy is one of the most observationally based sciences we’ve ever had. Everything we know about the sky has been a surprise. The ancients knew about the stars, but they didn’t know they were far away. They didn’t know they were like the Sun. Eventually we found that our own galaxy is one of hundreds of billions of galaxies and that the Universe is actually very old, but not infinitely old. So that was a big surprise too. Einstein thought, of course the Universe must have an infinite age, without a starting point. Well, he was wrong! Our intuition has just been wrong almost all the time. We’re pretty confident that we don’t know what we’re going to find.
Amber: As an astronomer one of the most exciting things about working on a telescope like this is the prospect of what it will tell us that we haven’t even thought of yet. We have all these really detailed science questions that we’ll ask, that we know to ask, and that we’ll answer. And in a sense that is what science is all about… in answering the questions we come up with more questions. There’s this almost infinite supply of questions, of things that we have to learn. So that’s why we build telescopes to get to this fundamental part of who we are as human beings. We’re explorers, and we want to learn about what our Universe is like.
Webb will be the world's premier space science observatory. It will solve mysteries in our solar system, look beyond to distant worlds around other stars and probe the mysterious structures and origins of our universe – including our place in it. Webb is an international project we’re leading with our partners, ESA (European Space Agency) and the Canadian Space Agency.
To learn more about our James Webb Space Telescope, visit the website, or follow the mission on Facebook, Twitter and Instagram.
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As our planet warms, Earth’s ocean and atmosphere are changing.
Climate change has a lot of impact on the ocean, from sea level rise to marine heat waves to a loss of biodiversity. Meanwhile, greenhouse gases like carbon dioxide continue to warm our atmosphere.
NASA’s upcoming satellite, PACE, is soon to be on the case!
Set to launch on Feb. 6, 2024, the Plankton, Aerosol, Cloud, ocean Ecosystem (PACE) mission will help us better understand the complex systems driving the global changes that come with a warming climate.
While a single phytoplankton typically can’t be seen with the naked eye, communities of trillions of phytoplankton, called blooms, can be seen from space. Blooms often take on a greenish tinge due to the pigments that phytoplankton (similar to plants on land) use to make energy through photosynthesis.
In a 2023 study, scientists found that portions of the ocean had turned greener because there were more chlorophyll-carrying phytoplankton. PACE has a hyperspectral sensor, the Ocean Color Instrument (OCI), that will be able to discern subtle shifts in hue. This will allow scientists to monitor changes in phytoplankton communities and ocean health overall due to climate change.
With PACE, scientists will be able to tell what phytoplankton communities are present – from space! Before, this could only be done by analyzing a sample of seawater.
Telling “who’s who” in a phytoplankton bloom is key because different phytoplankton play vastly different roles in aquatic ecosystems. They can fuel the food chain and draw down carbon dioxide from the atmosphere to photosynthesize. Some phytoplankton populations capture carbon as they die and sink to the deep ocean; others release the gas back into the atmosphere as they decay near the surface.
Studying these teeny tiny critters from space will help scientists learn how and where phytoplankton are affected by climate change, and how changes in these communities may affect other creatures and ocean ecosystems.
The PACE mission will offer important insights on airborne particles of sea salt, smoke, human-made pollutants, and dust – collectively called aerosols – by observing how they interact with light.
With two instruments called polarimeters, SPEXone and HARP2, PACE will allow scientists to measure the size, composition, and abundance of these microscopic particles in our atmosphere. This information is crucial to figuring out how climate and air quality are changing.
PACE data will help scientists answer key climate questions, like how aerosols affect cloud formation or how ice clouds and liquid clouds differ.
It will also enable scientists to examine one of the trickiest components of climate change to model: how clouds and aerosols interact. Once PACE is operational, scientists can replace the estimates currently used to fill data gaps in climate models with measurements from the new satellite.
With a view of the whole planet every two days, PACE will track both microscopic organisms in the ocean and microscopic particles in the atmosphere. PACE’s unique view will help us learn more about the ways climate change is impacting our planet’s ocean and atmosphere.
Stay up to date on the NASA PACE blog, and make sure to follow us on Tumblr for your regular dose of sPACE!
Even the most ambitious plans start with a drawing. Visualizing a distant destination or an ambitious dream is the first step to getting there. For decades, artists working on NASA projects have produced beautiful images that stimulated the imaginations of the people working to make them a reality.
Some of them offered visualizations of spacecraft that had not yet been built; others imagined what it might look like to stand on planets that had not yet been explored. This week, we look at 10 pieces of conceptual art for our missions before they were launched–along with actual photos taken when those missions arrived at their destinations.
1. Apollo at the Moon
In 1968, an artist with our contractor North American Rockwell illustrated a phase of the Apollo lunar missions, showing the Command and Service Modules over the surface of the Moon. In 1971, an astronaut aboard the Lunar Module during Apollo 15 captured a similar scene in person with a camera.
2. Ready for Landing
This artist’s concept depicts an Apollo Lunar Module firing its descent engine above the lunar surface. At right, a photo from Apollo 12 in 1969 showing the Lunar Module Intrepid, taken by Command Module Pilot Richard Gordon.
3. Man and Machine on the Moon
Carlos Lopez, an artist with Hughes Aircraft Company, created a preview of a Surveyor spacecraft landing for our Jet Propulsion Laboratory in the early 1960s. The robotic Surveyor missions soft landed on the Moon, collecting data and images of the surface in order to ensure a safe arrival for Apollo astronauts a few years later. In the image at right, Apollo 12 astronaut Alan Bean examines the Surveyor 3 spacecraft during his second excursion on the Moon in November 1969.
4. O Pioneer!
In missions that lived up to their names, we sent the Pioneer 10 and 11 spacecraft to perform the first up-close exploration of the outer solar system. At left, an artist’s imagining of Pioneer passing Jupiter. At right, Pioneer 11’s real view of the king of planets taken in 1974.
5. The Grand Tour
An even more ambitious pair of robotic deep space adventurers followed the Pioneers. Voyager 1 and 2 both visited Jupiter and Saturn. Voyager 2 went on to Uranus and Neptune. Even the most visionary artists couldn’t imagine the exotic and beautiful vistas that the Voyager spacecraft witnessed. These images were taken between 1979 and 1989.
6. Journey to a Giant
Our Cassini spacecraft carried a passenger to the Saturn system: the European Space Agency’s Huygens probe. Huygens was designed to land on Saturn’s planet-sized moon Titan. At left is an artist’s view of Cassini sending the Huygens probe on its way toward Titan, and at right are some actual images of the giant moon from Cassini’s cameras.
7. Titan Unveiled
On Jan. 14, 2005, the Huygens probe descended through Titan’s thick haze and revealed what Titan’s surface looks like for the first time in history. Before the landing, an artist imagined the landscape (left). During the descent, Huygens’ imagers captured the actual view at four different altitudes (center)—look for the channels formed by rivers of liquid hyrdocarbons. Finally, the probe came to rest on a pebble-strewn plain (right).
8. Hazy Skies over Pluto
David Seal rendered this imaginary view from the surface of Pluto, and in the sky above, an early version of the spacecraft that came to be known as our New Horizons. At the time, Pluto was already suspected of having a thin atmosphere. That turned out be true, as seen in this dramatic backlit view of Pluto’s hazy, mountainous horizon captured by one of New Horizons’ cameras in 2015.
9. Dreams on Mars, Wheels on Mars
Long before it landed in Gale Crater, our Curiosity rover was the subject of several artistic imaginings during the years the mission was in development. Now that Curiosity is actually rolling through the Martian desert, it occasionally stops to take a self-portrait with the camera at the end of its robotic arm, which it uses like a selfie stick.
10. The World, Ceres
No one knew exactly what the dwarf planet Ceres, the largest body in the asteroid belt, looked like until our Dawn mission got there. Dawn saw a heavily cratered world—with a few surprises, such as the famous bright spots in Occator crater.
There’s more to come. Today we have carefully created artist impressions of several unexplored destinations in the solar system, including the asteroids Psyche and Bennu, and an object one billion miles past Pluto that’s now called 2014 MU69.
You can help nickname this object (or objects—there may be two) by submitting your names by Dec. 1. Our New Horizons spacecraft will fly past MU69 on New Year’s Day 2019.
Soon, we’ll once again see how nature compares to our imaginations. It’s almost always stranger and more beautiful than we thought.
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The job of the our Technology Transfer Program is pretty straight-forward – bring NASA technology down to Earth. But, what does that actually mean? We’re glad you asked! We transfer the cool inventions NASA scientists develop for missions and license them to American businesses and entrepreneurs. And that is where the magic happens: those business-savvy licensees then create goods and products using our NASA tech. Once it hits the market, it becomes a “NASA Spinoff.”
If you’re imagining that sounds like a nightmare of paperwork and bureaucracy, think again. Our new automated “ATLAS” system helps you license your tech in no time — online and without any confusing forms or jargon.
So, sit back and browse this list of NASA tech ripe for the picking (well, licensing.) When you find something you like, follow the links below to apply for a license today! You can also browse the rest of our patent portfolio - full of hundreds of available technologies – by visiting technology.nasa.gov.
Ahh, fungus. It’s fun to say and fun to eat—if you are a mushroom fan. But, did you know it can play a crucial role in helping trees grow in contaminated soil? Scientists at our Ames Research Center discovered that a special type of the fungus among us called “Ectomycorrhizal” (or EM for short) can help enhance the growth of trees in areas that have been damaged, such as those from oil spills.
When it comes to aircraft, drag can be, well…a drag. Luckily, innovators at our Armstrong Flight Research Center are experimenting with a new wing design that removes adverse yaw (or unwanted twisting) and dramatically increases aircraft efficiency by reducing drag. Known as the “Preliminary Research Aerodynamic Design to Lower Drag (PRANDTL-D)” wing, this design addresses integrated bending moments and lift to achieve drag reduction.
What do aircraft, batteries, and furniture have in common? They can ALL be improved with our nanomaterials. Nanomaterials are very tiny materials that often have unique optical, electrical and mechanical properties. Innovators at NASA’s Glenn Research Center have developed a suite of materials and methods to optimize the performance of nanomaterials by making them tougher and easier to process. This useful stuff can also help electronics, fuel cells and textiles.
Industrial cleaning is hard work. It can also be expensive when you have to bring in chemicals to get things squeaky. Enter “Green Precision Cleaning,” which uses the nitrogen bubbles in water instead. The bubbles act as a scrubbing agent to clean equipment. Goddard Space Flight Center scientists developed this system for cleaning tubing and piping that significantly reduces cost and carbon consumption. Deionized water (or water that has been treated to remove most of its mineral ions) takes the place of costlier isopropyl alcohol (IPA) and also leaves no waste, which cuts out the pricey process of disposal. The cleaning system quickly and precisely removes all foreign matter from tubing and piping.
When it comes to working in space, smaller is always better. Innovators at our Johnson Space Center have developed a self-contained device for isolating microscopic materials like DNA, RNA, proteins, and cells without using pipettes or centrifuges. Think of this technology like a small briefcase full of what you need to isolate genetic material from organisms and microorganisms for analysis away from the lab. The device is also leak-proof, so users are protected from chemical hazards—which is good news for astronauts and Earth-bound scientists alike.
When it comes to “bringing the boom,” NASA does it better than anyone. But sometimes, we know it’s better to keep the decibels low. That’s why innovators at NASA’s Jet Propulsion Laboratory have developed a new handheld drilling device, suitable for a variety of operations, that is portable, rapid and quiet. Noise from drilling operations often becomes problematic because of the location or time of operations. Nighttime drilling can be particularly bothersome and the use of hearing protection in the high-noise areas may be difficult in some instances due to space restrictions or local hazards. This drill also weighs less than five pounds – talk about portable power.
The ability to detect damage to surfaces can be crucial, especially on a sealed environment that sustains human life or critical equipment. Enter Kennedy Space Center’s damage detection system for flat composite surfaces. The system is made up of layered composite material, with some of those layers containing the detection system imbedded right in. Besides one day potentially keeping humans safe on Mars, this tech can also be used on aircrafts, military shelters, inflatable structures and more.
We all know what a spoonful of sugar is capable of. But, who knew it could help make some materials stronger? Innovators at NASA’s Langley Research Center did! They use dehydrated sucrose to create yarns and woven sheets of carbon nanotubes and graphene.
The resulting materials are lightweight and strong. Sucrose is inexpensive and readily available, making the process cost-effective. Makes you look at the sweet substance a little differently, doesn’t it?
NASA scientists needed to find a way to friction weld that would be gentler on their welding equipment. Meet our next tech, ultrasonic stir welding.
NASA’s Marshall Space Flight Center engineers developed ultrasonic stir welding to join large pieces of very high-strength, high-melting-temperature metals such as titanium and Inconel. The addition of ultrasonic energy reduces damaging forces to the stir rod (or the piece of the unit that vibrates so fast, it joins the welding material together), extending its life. The technology also leaves behind a smoother, higher-quality weld.
It’s important to know that the fuel pumping into rockets has remained fully liquid or if a harmful chemical is leaking out of its container. But each of those things, and the many other places sensors are routinely used, tends to require a specially designed, one-use device.
That can result in time-consuming and costly cycles of design, test and build, since there is no real standardized sensor that can be adapted and used more widely.
To meet this need, the PiezoElectric Gravimeter (PEG) was developed to provide a sensing system and method that can serve as the foundation for a wide variety of sensing applications.
See anything your business could use? Did anything inspire you to start your own company? If so, head to our website at technology.nasa.gov to check them out.
When you’ve found what you need, click, “Apply Now!” Our licensing system, ATLAS, will guide you through the rest.
If the items on this round-up didn’t grab you, that’s ok, too. We have hundreds of other technologies available and ready to license on our website.
And if you want to learn more about the technologies already being used all around you, visit spinoff.nasa.gov.
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Our Space Launch System rocket is on the move this summer — literally. With the help of big and small businesses in all 50 states, various pieces of hardware are making their way to Louisiana for manufacturing, to Alabama for testing, and to Florida for final assembly. All of that work brings us closer to the launch of Artemis 1, SLS and Orion’s first mission to the Moon.
The SLS rocket will feature the largest core stage we have ever built before. It’s so large, in fact, that we had to modify and refurbish our barge Pegasus to accommodate the massive load. Pegasus was originally designed to transport the giant external tanks of the space shuttles on the 900-mile journey from our rocket factory, Michoud Assembly Facility, in New Orleans to Kennedy Space Center in Florida. Now, our barge ferries test articles from Michoud along the river to Huntsville, Alabama, for testing at Marshall Space Flight Center. Just a week ago, the last of four structural test articles — the liquid oxygen tank — was loaded onto Pegasus to be delivered at Marshall for testing. Once testing is completed and the flight hardware is cleared for launch, Pegasus will again go to work — this time transporting the flight hardware along the Gulf Coast from New Orleans to Cape Canaveral.
The massive, five-segment solid rocket boosters each weigh 1.6 million pounds. That’s the size of four blue whales! The only way to move the components for the powerful boosters on SLS from Promontory, Utah, to the Booster Fabrication Facility and Vehicle Assembly Building at Kennedy is by railway. That’s why you’ll find railway tracks leading from these assembly buildings and facilities to and from the launch pad, too. Altogether, we have about 38-mile industrial short track on Kennedy alone. Using a small fleet of specialized cars and hoppers and existing railways across the US, we can move the large, bulky equipment from the Southwest to Florida’s Space Coast. With all the motor segments complete in January, the last booster motor segment (pictured above) was moved to storage in Utah. Soon, trains will deliver all 10 segments to Kennedy to be stacked with the booster forward and aft skirts and prepared for flight.
A regular passenger airplane doesn’t have the capacity to carry the specialized hardware for SLS and our Orion spacecraft. Equipped with a unique hinged nose that can open more than 200 degrees, our Super Guppy airplane is specially designed to carry the hulking hardware, like the Orion stage adapter, to the Cape. That hinged nose means cargo is actually loaded from the front, not the back, of the airplane. The Orion stage adapter, delivered to Kennedy in 2018, joins to the rocket’s interim cryogenic propulsion stage, which will give our spacecraft the push it needs to go to the Moon on Artemis 1. It fit perfectly inside the Guppy’s cargo compartment, which is 25 feet tall and 25 feet wide and 111 feet long.
In the end, all roads lead to Kennedy, and the star of the transportation show is really the “crawler.” Rolling along at a delicate 1 MPH when it’s loaded with the mobile launcher, our two crawler-transporters are vital in bringing the fully assembled rocket to the launchpad for each Artemis mission. Each the size of a baseball field and powered by locomotive and large power generator engines, one crawler-transporter is able to carry 18 million pounds on the nine-mile journey to the launchpad. As of June 27, 2019, the mobile launcher atop crawler-transporter 2 made a successful final test roll to the launchpad, clearing the transporter and mobile launcher ready to carry SLS and Orion to the launchpad for Artemis 1.
It takes a lot of team work to launch Artemis 1. We are partnering with Boeing, Northrop Grumman and Aerojet Rocketdyne to produce the complex structures of the rocket. Every one of our centers and more than 1,200 companies across the United States support the development of the rocket that will launch Artemis 1 to the Moon and, ultimately, to Mars. From supplying key tools to accelerate the development of the core stage to aiding the transportation of the rocket closer to the launchpad, companies like Futuramic in Michigan and Major Tool & Machine in Indiana, are playing a vital role in returning American astronauts to the Moon. This time, to stay. To stay up to date with the latest SLS progress, click here.
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Does the object in this image look like a mirror? Maybe not, but that’s exactly what it is! To be more precise, it’s a set of mirrors that will be used on an X-ray telescope. But why does it look nothing like the mirrors you’re familiar with? To answer that, let’s first take a step back. Let’s talk telescopes.
The basic function of a telescope is to gather and focus light to amplify the light’s source. Astronomers have used telescopes for centuries, and there are a few different designs. Today, most telescopes use curved mirrors that magnify and focus light from distant objects onto your eye, a camera, or some other instrument. The mirrors can be made from a variety of materials, including glass or metal.
Space telescopes like the James Webb and Hubble Space Telescopes use large mirrors to focus light from some of the most distant objects in the sky. However, the mirrors must be tailored for the type and range of light the telescope is going to capture—and X-rays are especially hard to catch.
X-rays tend to zip through most things. This is because X-rays have much smaller wavelengths than most other types of light. In fact, X-rays can be smaller than a single atom of almost every element. When an X-ray encounters some surfaces, it can pass right between the atoms!
Doctors use this property of X-rays to take pictures of what’s inside you. They use a beam of X-rays that mostly passes through skin and muscle but is largely blocked by denser materials, like bone. The shadow of what was blocked shows up on the film.
This tendency to pass through things includes most mirrors. If you shoot a beam of X-rays into a standard telescope, most of the light would go right through or be absorbed. The X-rays wouldn’t be focused by the mirror, and we wouldn’t be able to study them.
X-rays can bounce off a specially designed mirror, one turned on its side so that the incoming X-rays arrive almost parallel to the surface and glance off it. At this shallow angle, the space between atoms in the mirror's surface shrinks so much that X-rays can't sneak through. The light bounces off the mirror like a stone skipping on water. This type of mirror is called a grazing incidence mirror.
Telescope mirrors curve so that all of the incoming light comes to the same place. Mirrors for most telescopes are based on the same 3D shape — a paraboloid. You might remember the parabola from your math classes as the cup-shaped curve. A paraboloid is a 3D version of that, spinning it around the axis, a little like the nose cone of a rocket. This turns out to be a great shape for focusing light at a point.
Mirrors for visible and infrared light and dishes for radio light use the “cup” portion of that paraboloid. For X-ray astronomy, we cut it a little differently to use the wall. Same shape, different piece. The mirrors for visible, infrared, ultraviolet, and radio telescopes look like a gently-curving cup. The X-ray mirror looks like a cylinder with very slightly angled walls.
The image below shows how different the mirrors look. On the left is one of the Chandra X-ray Observatory’s cylindrical mirrors. On the right you can see the gently curved round primary mirror for the Stratospheric Observatory for Infrared Astronomy telescope.
If we use just one grazing incidence mirror in an X-ray telescope, there would be a big hole, as shown above (left). We’d miss a lot of X-rays! Instead, our mirror makers fill in that cylinder with layers and layers of mirrors, like an onion. Then we can collect more of the X-rays that enter the telescope, giving us more light to study.
Nested mirrors like this have been used in many X-ray telescopes. Above is a close-up of the mirrors for an upcoming observatory called the X-ray Imaging and Spectroscopy Mission (XRISM, pronounced “crism”), which is a Japan Aerospace Exploration Agency (JAXA)-led international collaboration between JAXA, NASA, and the European Space Agency (ESA).
The XRISM mirror assembly uses thin, gold-coated mirrors to make them super reflective to X-rays. Each of the two assemblies has 1,624 of these layers packed in them. And each layer is so smooth that the roughest spots rise no more than one millionth of a millimeter.
Why go to all this trouble to collect this elusive light? X-rays are a great way to study the hottest and most energetic areas of the universe! For example, at the centers of certain galaxies, there are black holes that heat up gas, producing all kinds of light. The X-rays can show us light emitted by material just before it falls in.
Stay tuned to NASA Universe on Twitter and Facebook to keep up with the latest on XRISM and other X-ray observatories.
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On March 14, we will join people across the U.S. as they celebrate an icon of nerd culture: the number pi.
So well known and beloved is pi, also written π or 3.14, that it has a national holiday named in its honor. And it’s not just for mathematicians and rocket scientists. National Pi Day is widely celebrated among students, teachers and science fans, too. Read on to find out what makes pi so special, how it’s used to explore space and how you can join the celebration with resources from our collection.
Pi, also written π, is the Swiss Army knife of numbers. No matter how big or small a circle – from the size of our universe all the way down to an atom or smaller – the ratio of a circle’s circumference (the distance around it) to its diameter (the distance across it) is always equal to pi. Most commonly, pi is used to answer questions about anything circular or spherical, so it comes in handy especially when you’re dealing with space exploration.
For simplicity, pi is often rounded to 3.14, but its digits go on forever and don’t appear to have any repeating patterns. While people have made it a challenge to memorize record-breaking digits of pi or create computer programs to calculate them, you really don’t need that many digits for most calculations – even at NASA. Here’s one of our engineers on how many decimals of pi you need.
Pi pops up in everything from rocket-science-level math to the stuff you learn in elementary school, so it’s gained a sort of cult following. On March 14 (or 3/14 in U.S. date format) in 1988, a physicist at the San Francisco Exploratorium held what is thought to be the first official Pi Day celebration, which smartly included the consumption of fruit pies. Math teachers quickly realized the potential benefits of teaching students about pi while they ate pie, and it all caught on so much that in 2009, the U.S. Congress officially declared March 14 National Pi Day. Here’s how to turn your celebration into a teachable moment.
Space is full of circular and spherical features, and to explore them, engineers at NASA build spacecraft that make elliptical orbits and guzzle fuel from cylindrical fuel tanks, and measure distances on circular wheels. Beyond measurements and space travel, pi is used to find out what planets are made of and how deep alien oceans are, and to study newly discovered worlds. In other words, pi goes a long way at NASA.
No Pi Day is complete without a little problem solving. Even the math-averse will find something to love about this illustrated math challenge that features real questions scientists and engineers must answer to explore and study space – like how to determine the size of a distant planet you can’t actually see. Four new problems are added to the challenge each year and answers are released the day after Pi Day.
For teachers, the question is not whether to celebrate Pi Day, but how to celebrate it. (And how much pie is too much? Answer: The limit does not exist.) Luckily, our Education Office has an online catalog for teachers with all 20 of its “Pi in the Sky” math challenge questions for grades 4-12. Each lesson includes a description of the real-world science and engineering behind the problem, an illustrated handout and answer key, and a list of applicable Common Core Math and Next Generation Science Standards.
In a way, we celebrate Pi Day every day by using pi to explore space. But in our free time, we’ve been known to make and eat space-themed pies, too! Share your own nerdy celebrations with us here.
The fascination with pi, as well its popularity and accessibility have made it a go-to math reference in books, movies and television. Ellie, the protagonist in Carl Sagan’s book “Contact,” finds a hidden message from aliens in the digits of pi. In the original “Star Trek” series, Spock commanded an alien entity that had taken over the computer to compute pi to the last digit – an impossible task given that the digits of pi are infinite. And writers of “The Simpsons,” a show known for referencing math, created an episode in which Apu claims to know pi to 40,000 digits and proves it by stating that the 40,000th digit is 1.
Calculating record digits of pi has been a pastime of mathematicians for millennia. Until the 1900s, these calculations were done by hand and reached records in the 500s. Once computers came onto the scene, that number jumped into the thousands, millions and now trillions. Scientist and pi enthusiast Peter Trueb holds the current record – 22,459,157,718,361 digits – which took his homemade computer 105 days of around-the-clock number crunching to achieve. The record for the other favorite pastime of pi enthusiasts, memorizing digits of pi, stands at 70,030.
As passionate as people are about pi, there are some who believe things would be a whole lot better if we replaced pi with a number called tau, which is equal to 2π or 6.28. Because many formulas call for 2π, tau-enthusiasts say tau would provide a more elegant and efficient way to express those formulas. Every year on Pi Day, a small debate ensues. While we won’t take sides, we will say that pi is more widely used at NASA because it has applications far beyond geometry, where 2π is found most often. Perhaps most important, though, for pi- and pie-lovers alike is there’s no delicious homonym for tau.
Enjoy the full version of this article HERE.
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When it comes to climate change, we play a unique role in observing and understanding changes to the planet. Thanks to NASA’s Earth observations and related research, we know our planet and its climate are changing profoundly. We also know human activities, like releasing carbon dioxide and methane into the atmosphere, are driving this change.
Not only do we make these observations, we help people and groups use this knowledge to benefit society. The work we do at NASA is critical to helping us understand the ways our planet is responding to increased temperatures.
Here are 6 ways that we are involved in climate science and informing decisions:
Just like a doctor checks your vitals when you go in for a visit, here at NASA we are constantly monitoring Earth’s vital signs - carbon dioxide levels, global temperature, Arctic sea ice minimum, the ice sheets and sea level, and more.
We use satellites in space, observations from airplanes and ships, and data collected on the ground to understand our planet and its changing climate. Scientists also use computers to model and understand what's happening now and what might happen in the future.
People who study Earth see that the planet’s climate is getting warmer. Earth's temperature has gone up more than 1 degree Celsius (~2 degrees Fahrenheit) in the last 100 years. This may not seem like much, but small changes in Earth's temperature can have big effects. The current warming trend is of particular significance, because it is predominantly the result of human activity since the mid-20th century and is proceeding at an unprecedented rate.
People drive cars. People heat and cool their houses. People cook food. All those things take energy. Human-produced greenhouse gas emissions are largely responsible for warming our planet. Burning fossil fuels -- which includes coal, oil, and natural gas -- releases greenhouse gases such as carbon dioxide into the atmosphere, where they act like an insulating blanket and trap heat near Earth’s surface.
At NASA, we use satellites and instruments on board the International Space Station to confirm measurements of atmospheric carbon levels. They’ve been increasing much faster than any other time in history.
We also monitor and track global land use. Currently, half the world's population lives in urban areas, and by 2025, the United Nations projects that number will rise to 60%.
With so many people living and moving to metropolitan areas, the scientific world recognizes the need to study and understand the impacts of urban growth both locally and globally.
The International Space Station helps with this effort to monitor Earth. Its position in low-Earth orbit provides variable views and lighting over more than 90% of the inhabited surface of Earth, a useful complement to sensor systems on satellites in higher-altitude polar orbits. This high-resolution imaging of land and sea allows tracking of urban and forest growth, monitoring of hurricanes and volcanic eruptions, documenting of melting glaciers and deforestation, understanding how agriculture may be impacted by water stress, and measuring carbon dioxide in Earth’s atmosphere.
Being able to monitor Earth’s climate from space also allows us to understand what’s driving these changes.
With the CERES instruments, which fly on multiple Earth satellites, our scientists measure the Earth’s planetary energy balance – the amount of energy Earth receives from the Sun and how much it radiates back to space. Over time, less energy being radiated back to space is evidence of an increase in Earth’s greenhouse effect. Human emissions of greenhouse gases are trapping more and more heat.
NASA scientists also use computer models to simulate changes in Earth’s climate as a result of human and natural drivers of temperature change.
These simulations show that human activities such as greenhouse gas emissions, along with natural factors, are necessary to simulate the changes in Earth’s climate that we have observed; natural forces alone can’t do so.
Global climate change has already had observable effects on the environment. Glaciers and ice sheets have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted, and trees are flowering sooner.
The effects of global climate change that scientists predicted are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves.
Climate modelers have predicted that, as the planet warms, Earth will experience more severe heat waves and droughts, larger and more extreme wildfires, and longer and more intense hurricane seasons on average. The events of 2020 are consistent with what models have predicted: extreme climate events are more likely because of greenhouse gas emissions.
Plants are also struggling to keep up with rising carbon dioxide levels. Plants play a key role in mitigating climate change. The more carbon dioxide they absorb during photosynthesis, the less carbon dioxide remains trapped in the atmosphere where it can cause temperatures to rise. But scientists have identified an unsettling trend – 86% of land ecosystems globally are becoming progressively less efficient at absorbing the increasing levels of carbon dioxide from the atmosphere.
Helping organizations to use all the data and knowledge NASA generates is another part of our job. We’ve helped South Dakota fight West Nile Virus, helped managers across the Western U.S. handle water, helped The Nature Conservancy protect land for shorebirds, and others. We also support developing countries as they work to address climate and other challenges through a 15-year partnership with the United States Agency for International Development.
Sustainability involves taking action now to enable a future where the environment and living conditions are protected and enhanced. We work with many government, nonprofit, and business partners to use our data and modeling to inform their decisions and actions. We are also working to advance technologies for more efficient flight, including hybrid-electric propulsion, advanced materials, artificial intelligence, and machine learning.
These advances in research and technology will not only bring about positive changes to the climate and the world in which we live, but they will also drive the economic engine of America and our partners in industry, to remain the world-wide leader in flight development.
We partner with the private sector to facilitate the transfer of our research and NASA-developed technologies. Many innovations originally developed for use in the skies above help make life more sustainable on Earth. For example:
Our Earth-observing satellites help farmers produce more with less water.
Expertise in rocket engineering led to a technique that lessens the environmental impact of burning coal.
A fuel cell that runs equipment at oil wells reduces the need to vent greenhouse gases.
Sea level rise in the two-thirds of Earth covered by water may jeopardize up to two-thirds of NASA's infrastructure built within mere feet of sea level.
Some NASA centers and facilities are located in coastal real estate because the shoreline is a safer, less inhabited surrounding for launching rockets. But now these launch pads, laboratories, airfields, and testing facilities are potentially at risk because of sea level rise. We’ve worked internally at NASA to identify climate risks and support planning at our centers.
Climate change is one of the most complex issues facing us today. It involves many dimensions – science, economics, society, politics, and moral and ethical questions – and is a global problem, felt on local scales, that will be around for decades and centuries to come. With our Eyes on the Earth and wealth of knowledge on the Earth’s climate system and its components, we are one of the world’s experts in climate science.
Visit our Climate site to explore and learn more.
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Our Milky Way galaxy is full of hundreds of billions of worlds just waiting to be found. In 2014, scientists using data from our planet-hunting Kepler space telescope discovered seven planets orbiting Kepler-90, a Sun-like star located 2,500 light-years away. Now, an eighth planet has been identified in this planetary system, making it tied with our own solar system in having the highest number of known planets. Here’s what you need to know:
Kepler-90i is a sizzling hot, rocky planet. It’s the smallest of eight planets in the Kepler-90 system. It orbits so close to its star that a “year” passes in just 14 days.
Average surface temperatures on Kepler-90i are estimated to hover around 800 degrees Fahrenheit, making it an unlikely place for life as we know it.
The Kepler-90 system is set up like our solar system, with the small planets located close to their star and the big planets farther away. This pattern is evidence that the system’s outer gas planets—which are about the size of Saturn and Jupiter—formed in a way similar to our own.
But the orbits are much more compact. The orbits of all eight planets could fit within the distance of Earth’s orbit around our Sun! Sounds crowded, but think of it this way: It would make for some great planet-hopping.
Most planets beyond our solar system are too far away to be imaged directly. The Kepler space telescope searches for these exoplanets—those planets orbiting stars beyond our solar system—by measuring how the brightness of a star changes when a planet transits, or crosses in front of its disk. Generally speaking, for a given star, the greater the dip in brightness, the bigger the planet!
Researchers trained a computer to learn how to identify the faint signal of transiting exoplanets in Kepler’s vast archive of deep-space data. A search for new worlds around 670 known multiple-planet systems using this machine-learning technique yielded not one, but two discoveries: Kepler-90i and Kepler-80g. The latter is part of a six-planet star system located 1,000 light-years away.
Kepler-90 is the first known star system besides our own that has eight planets, but scientists say it won’t be the last. Other planets may lurk around stars surveyed by Kepler. Next, researchers are using machine learning with sophisticated computer algorithms to search for more planets around 150,000 stars in the Kepler database.
Kepler is the most successful planet-hunting spacecraft to date, with more than 2,500 confirmed exoplanets and many more awaiting verification. Future space missions, like the Transiting Exoplanet Survey Satellite (TESS), the James Webb Space Telescope and Wide-Field Infrared Survey Telescope (WFIRST) will continue the search for new worlds and even tell us which ones might offer promising homes for extraterrestrial life.
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*All images of exoplanets are artist illustrations.
When we talk about exploration in far-flung places, you might think of space telescopes taking images of planets outside our solar system, or astronauts floating on the International Space Station.
But did you know our researchers travel to some of Earth's most inaccessible and dangerous places, too?
Two scientists working with the ICESat-2 mission just finished a trek from the South Pole to latitude 88 south, a journey of about 450 miles. They had to travel during the Antarctic summer - the region's warmest time, with near-constant sunshine - but the trek was still over solid ice and snow.
The trip lasted 14 days, and was an important part of a process known as calibration and validation. ICESat-2 will launch this fall, and the team was taking extremely precise elevation measurements that will be used to validate those taken by the satellite.
Sometimes our research in Earth's remote regions helps us understand even farther-flung locations…like other planets.
Geologic features on Mars look very similar to islands and landforms created by volcanoes here on our home planet.
As hot jets of magma make their way to Earth's surface, they create new rocks and land - a process that may have taken place on Mars and the Moon.
In 2015, our researchers walked on newly cooled lava on the Holuhraun volcano in Iceland to take measurements of the landscape, in order to understand similar processes on other rocky bodies in our solar system.
There may not be flowing lava in the mangrove forests in Gabon, but our researchers have to brave mosquitoes and tree roots that reach up to 15-foot high as they study carbon storage in the vegetation there.
The scientists take some measurements from airplanes, but they also have to gather data from the ground in one our of planet's most pristine rainforests, climbing over and around roots that can grow taller than people. They use these measurements to create a 3-D map of the ecosystem, which helps them understand how much carbon in stored in the plants.
You can follow our treks to Earth’s most extreme locales on our Earth Expeditions blog.
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Tomorrow, Feb. 18, 2021, our most advanced rover named Perseverance will attempt a precision landing in Mars' Jezero Crater. Her mission is to search for signs of ancient life in the planet's geology and test technology that will pave the way for future human missions to the Moon and Mars. Excited yet? Get this:
Perseverance is ferrying 25 cameras to the Red Planet — the most ever flown in the history of deep-space exploration — so get ready to see Mars like never before! For more mission quick facts, click here.
Date: Feb. 18
Time: Live coverage starts at 2:15 p.m. EST (19:15 UTC)
Want to join the #CountdownToMars? We created a virtual Mars photo booth, have sounds of Mars to listen to and more for all you Earthlings to channel your inner Martian. Check out ways to participate HERE.
If you want to follow Perseverance's journey on the Red Planet, be sure to follow her on Facebook and Twitter.
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