Mars is hard. Forty years ago this week, our Viking mission found a place in history when it became the first U.S. mission to land a spacecraft safely on the surface of Mars and return images of the surface. This is astonishing considering that many of the spacecraft destined for Mars failed before completing their missions and some failed before their observations could begin.
Here’s a few things to know about the Viking missions that ushered in a new era of Mars explorations 40 years ago:
1. Multi Mission
The Viking mission consisted of four spacecraft – two orbiters and two landers. All four made significant science discoveries.
2. Last Minute Switch
The spacecraft eventually named Viking 2 was supposed to launch first, but a battery problem prompted us to send the second spacecraft first. Batteries recharged, Viking 2 was then sent to rendezvous with the Red Planet.
3. Not Quite the First
Viking 1 was the first to send back science from the surface of Mars, but the honor of the first Mars landing goes to the Soviet Union’s Mars 3. The Soviet spacecraft landed on Mars in December 1970, but sent back only 20 seconds of video data before going silent.
4. Viking 1 Quick Stats
Viking 1 was launched Aug. 20 1975, and arrived at Mars on June 19, 1976. On July 20, 1976, the Viking 1 lander separated from the orbiter and touched down at Chryse Planitia.
5. Viking 2 Quick Stats
Viking 2 was launched Sept. 9, 1975, and entered Mars orbit Aug. 7, 1976. The Viking 2 lander touched down at Utopia Planitia on Sept. 3, 1976.
Discover the full list of 10 things to know about our solar system this week HERE.
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Earth is a dynamic and stormy planet with everything from brief, rumbling thunderstorms to enormous, raging hurricanes, which are some of the most powerful and destructive storms on our world. But other planets also have storm clouds, lightning — even rain, of sorts. Let’s take a tour of some of the unusual storms in our solar system and beyond.
Tune in May 22 at 3 p.m. for more solar system forecasting with NASA Chief Scientist Jim Green during the latest installment of NASA Science Live: https://www.nasa.gov/nasasciencelive.
Mercury, the planet nearest the Sun, is scorching hot, with daytime temperatures of more than 800 degrees Fahrenheit (about 450 degrees Celsius). It also has weak gravity — only about 38% of Earth's — making it hard for Mercury to hold on to an atmosphere.
Its barely there atmosphere means Mercury doesn’t have dramatic storms, but it does have a strange "weather" pattern of sorts: it’s blasted with micrometeoroids, or tiny dust particles, usually in the morning. It also has magnetic “tornadoes” — twisted bundles of magnetic fields that connect the planet’s magnetic field to space.
Venus is often called Earth's twin because the two planets are similar in size and structure. But Venus is the hottest planet in our solar system, roasting at more than 800 degrees Fahrenheit (430 degrees Celsius) under a suffocating blanket of sulfuric acid clouds and a crushing atmosphere. Add to that the fact that Venus has lightning, maybe even more than Earth.
In visible light, Venus appears bright yellowish-white because of its clouds. Earlier this year, Japanese researchers found a giant streak-like structure in the clouds based on observations by the Akatsuki spacecraft orbiting Venus.
Earth has lots of storms, including thunderstorms, blizzards and tornadoes. Tornadoes can pack winds over 300 miles per hour (480 kilometers per hour) and can cause intense localized damage.
But no storms match hurricanes in size and scale of devastation. Hurricanes, also called typhoons or cyclones, can last for days and have strong winds extending outward for 675 miles (1,100 kilometers). They can annihilate coastal areas and cause damage far inland.
Mars is infamous for intense dust storms, including some that grow to encircle the planet. In 2018, a global dust storm blanketed NASA's record-setting Opportunity rover, ending the mission after 15 years on the surface.
Mars has a thin atmosphere of mostly carbon dioxide. To the human eye, the sky would appear hazy and reddish or butterscotch colored because of all the dust suspended in the air.
It’s one of the best-known storms in the solar system: Jupiter’s Great Red Spot. It’s raged for at least 300 years and was once big enough to swallow Earth with room to spare. But it’s been shrinking for a century and a half. Nobody knows for sure, but it's possible the Great Red Spot could eventually disappear.
Saturn has one of the most extraordinary atmospheric features in the solar system: a hexagon-shaped cloud pattern at its north pole. The hexagon is a six-sided jet stream with 200-mile-per-hour winds (about 322 kilometers per hour). Each side is a bit wider than Earth and multiple Earths could fit inside. In the middle of the hexagon is what looks like a cosmic belly button, but it’s actually a huge vortex that looks like a hurricane.
Storm chasers would have a field day on Saturn. Part of the southern hemisphere was dubbed "Storm Alley" by scientists on NASA's Cassini mission because of the frequent storm activity the spacecraft observed there.
Earth isn’t the only world in our solar system with bodies of liquid on its surface. Saturn’s moon Titan has rivers, lakes and large seas. It’s the only other world with a cycle of liquids like Earth’s water cycle, with rain falling from clouds, flowing across the surface, filling lakes and seas and evaporating back into the sky. But on Titan, the rain, rivers and seas are made of methane instead of water.
Data from the Cassini spacecraft also revealed what appear to be giant dust storms in Titan’s equatorial regions, making Titan the third solar system body, in addition to Earth and Mars, where dust storms have been observed.
Scientists were trying to solve a puzzle about clouds on the ice giant planet: What were they made of? When Voyager 2 flew by in 1986, it spotted few clouds. (This was due in part to the thick haze that envelops the planet, as well as Voyager's cameras not being designed to peer through the haze in infrared light.) But in 2018, NASA’s Hubble Space Telescope snapped an image showing a vast, bright, stormy cloud cap across the north pole of Uranus.
Neptune is our solar system's windiest world. Winds whip clouds of frozen methane across the ice giant planet at speeds of more than 1,200 miles per hour (2,000 kilometers per hour) — about nine times faster than winds on Earth.
Neptune also has huge storm systems. In 1989, NASA’s Voyager 2 spotted two giant storms on Neptune as the spacecraft zipped by the planet. Scientists named the storms “The Great Dark Spot” and “Dark Spot 2.”
Scientists using NASA’s Hubble Space Telescope made a global map of the glow from a turbulent planet outside our solar system. The observations show the exoplanet, called WASP-43b, is a world of extremes. It has winds that howl at the speed of sound, from a 3,000-degree-Fahrenheit (1,600-degree-Celsius) day side, to a pitch-black night side where temperatures plunge below 1,000 degrees Fahrenheit (500 degrees Celsius).
Discovered in 2011, WASP-43b is located 260 light-years away. The planet is too distant to be photographed, but astronomers detected it by observing dips in the light of its parent star as the planet passes in front of it.
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Which do you think you'll miss more after your first trip? Space when you're back on Earth or Earth when you're up in Space?
I think that I will miss space when I’m back on Earth. One astronaut when she returned said that gravity sucks, so I’m looking forward to finding out what that’s like.
Dr. Erika Podest is a scientist with the Carbon Cycle and Ecosystems Group in our Jet Propulsion Laboratory’s Earth Science Division and Visiting Associate Researcher in the Joint Institute for Regional Earth System Science and Engineering (JIFRESSE) at UCLA. Her research entails using satellite images to study Earth’s ecosystems specifically related to wetlands and boreal forests and how they are being affected by climate change.
Erika took time from studying our home planet to answer questions about her life and career! Get to know our Earth Scientist:
I am inspired by the beauty of nature, its perfection and by the peace it brings me. My motivation is to make a positive impact on our planet by better understanding it and caring for it.
I was born and raised in Panama, which is a country with an exuberant nature. Since I can remember, I was always surrounded by nature because my father was an adventurer who loved the outdoors and always took me with him to go exploring or simply to enjoy a nice relaxing day outside. This led me to develop a deep sense of appreciation, respect, and curiosity for nature, which sparked my interest to learn about it and pursue a career in Earth Science.
Early in my college years I was training for my private pilot’s license and during my solo flights I would take pictures of features on the surface from the plane. I was always amazed at the details the pictures showed of the landscape that were not obvious from the ground. This was the first step towards discovering that there was a field for studying Earth from above, called remote sensing and consequently my Masters and Ph.D. were focused in this field.
I don’t think it is a matter of any one technology, discovery or policy. It is a combination of everything. Having an impact on climate change involves every level and direction, from the bottom up at the individual, grassroots and community level to the top down at the policy level. As individuals, I think it is important to educate ourselves about climate change (I suggest climate.nasa.gov). We all have the power to make a positive change by speaking up and making informed decisions about our consumptive habits.
Wetlands provide a vital role in carbon storage. Even though they cover about 5-8% of the Earth’s land surface, studies indicate that they contain a disproportionate amount of our planet’s total soil carbon, about 20-30%. In addition, they are like the arteries and veins of the landscape, acting as water sources and purifiers and helping in flood control. They also protect our shores and harbor large amounts of biodiversity.
Boreal forests are found in the uppermost northern hemisphere (Alaska, most of Canada, Russia, Scandinavia and northern Asia) and account for about 30% of the world’s forest cover. These forests lock up enormous amounts of carbon and help slow the increasing buildup of carbon dioxide in our atmosphere. In their peak growth phase during the northern spring and summer, the worldwide levels of carbon dioxide fall and the worldwide levels of oxygen rise.
It depends on the research trip. For example, one of my more recent ones was to the Peruvian Amazon where we went upriver on a boat for three weeks on a major tributary of the Amazon River called the Ucuyali River. I was with a team of eight researchers and we were studying the wetland ecosystems of the Pacaya-Samiria Natural Reserve, which entailed making vegetation measurements and assessing inundation extent to validate our scientific findings from satellite observations. We camped for most of the trip and a typical day entailed waking up at around 5:00 am with a symphony of sounds that emerged from the forest, including monkeys. We had breakfast and set off from base camp into the forest (~1 hour walk) to work an 8-9 hour day with a short lunch break (we had packed lunches) at noon. At the end of the day I’d be drenched in sweat, sunscreen, insect repellent, and dust and I’d bathe with water from the river, which was as brown as a milk chocolate bar. It was the most refreshing and cleansing feeling! The day would close with dinner followed with a discussion of the measurements to be collected the following day. Lights were out by 7:30 pm (which seemed like midnight) and I’d re-emerge myself into my tent in the dark tropical night surrounded by the sounds of the forest, until the next morning.
That it is important to be patient, humble and thankful.
Great question! I do not have any secrete skills or talents but I do have a couple of hobbies. I play the piano, though I am still a novice. I love windsurfing. It is an amazing feeling to skim over the water at fast speeds (I’m also an adrenaline junkie). Finally, I am fascinated by magic card tricks and whenever I have some free time I like to learn a new trick.
I enjoy constantly learning about our natural world and how it works. I also really enjoy communicating my work to students and to the general public. I find it especially rewarding when I can educate people and motivate students to consider careers in science.
Erika, thank you for your time and everything you do to keep our home planet safe!
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You might have heard, One Direction filmed their ‘Drag Me Down’ music video at NASA’s Johnson Space Center, and we know you’re dying to take a tour of everything they saw. So, here we go…
1) Space Exploration Vehicle (SEV)
Even though Louis is roving around Johnson Space Center in our Space Exploration Vehicle, its intended destination is quite different. The SEV will be used for in-space missions and for surface explorations of planetary bodies, including near-Earth asteroids and Mars!
2) Robonaut
Harry and Robonaut bonded during their visit to Johnson Space Center for the filming of their music video. This robot will help humans work and explore in space. Working side by side with humans, or going where the risks are too great for people, robots will make it so we never get ‘dragged down’!
3) Partial Gravity Simulator & Space Station Mockup Bike
You can find Niall floating around in our Partial Gravity Simulator, aka POGO, in the new music video. This tool is used to provide accurate simulations of reduced gravity. Astronauts use this for training and to learn how to perform tasks in space.
While Niall floats with POGO, Liam is training on the International Space Station Mockup Bike, aka CEVIS. This bike provides aerobic exercise and is used to countermeasure the harmful effects of exposure to microgravity while on the space station.
4) Orion Spacecraft
The Orion spacecraft will be the first of its kind that will carry humans to deep space and to Mars! It will be the safest, most advanced spacecraft ever built, and Harry, Niall, Louis and Liam all got to check it out.
5) T-38 Jets
Flying these T-38 jet trainers are an important part of preparing to be an astronaut. Flying and landing them acts as a real-life simulation for practicing spacecraft operations. They can even fly at supersonic up to Mach 1.6, and can put their pilots through more than seven Gs!
Did Mars once have life? To help answer that question, an international team of scientists created an incredibly powerful miniature chemistry laboratory, set to ride on the next Mars rover.
The instrument, called the Mars Organic Molecule Analyzer Mass Spectrometer (MOMA-MS), will form a key part of the ExoMars Rover, a joint mission between the European Space Agency (ESA) and Roscosmos. A mass spectrometer is crucial to send to Mars because it reveals the elements that can be found there. A Martian mass spectrometer takes a sample, typically of powdered rock, and distinguishes the different elements in the sample based on their mass.
After 8 years of designing, building, and testing, NASA scientists and engineers from NASA’s Goddard Space Flight Center said goodbye to their tiny chemistry lab and shipped it to Italy in a big pink box. Building a tiny instrument capable of conducting chemical analysis is difficult in any setting, but designing one that has to launch on a huge rocket, fly through the vacuum of space, and then operate on a planet with entirely different pressure and temperature systems? That’s herculean. And once on Mars, MOMA has a very important job to do. NASA Goddard Center Director Chris Scolese said, “This is the first intended life-detecting instrument that we have sent to Mars since Viking.”
The MOMA instrument will be capable of detecting a wide variety of organic molecules. Organic compounds are commonly associated with life, although they can be created by non-biological processes as well. Organic molecules contain carbon and hydrogen, and can include oxygen, nitrogen, and other elements.
To find these molecules on Mars, the MOMA team had to take instruments that would normally occupy a couple of workbenches in a chemistry lab and shrink them down to roughly the size of a toaster oven so they would be practical to install on a rover.
MOMA-MS, the mass spectrometer on the ExoMars rover, will build on the accomplishments from the Sample Analysis at Mars (SAM), an instrument suite on the Curiosity rover that includes a mass spectrometer. SAM collects and analyzes samples from just below the surface of Mars while ExoMars will be the first to explore deep beneath the surface, with a drill capable of taking samples from as deep as two meters (over six feet). This is important because Mars’s thin atmosphere and spotty magnetic field offer little protection from space radiation, which can gradually destroy organic molecules exposed on the surface. However, Martian sediment is an effective shield, and the team expects to find greater abundances of organic molecules in samples from beneath the surface.
On completion of the instrument, MOMA Project Scientist Will Brinckerhoff praised his colleagues, telling them, “You have had the right balance of skepticism, optimism, and ambition. Seeing this come together has made me want to do my best.”
In addition to the launch of the ESA and Roscosmos ExoMars Rover, in 2020, NASA plans to launch the Mars 2020 Rover, to search for signs of past microbial life. We are all looking forward to seeing what these two missions will find when they arrive on our neighboring planet.
Learn more about MOMA HERE.
Learn more about ExoMars HERE.
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uhmm, can you tell me what exactly a black hole is? or what iy does? thanks, just really confused and curious on how it actually works.
During nearly two decades in space, Cassini has been a source of inspiration to many. Has Cassini inspired you? Upload your artwork, photos, poems or songs to the social media platform of your choice, such as Instagram, YouTube, Facebook, Twitter or others. Tag it #CassiniInspires. Or, send it directly to: cassinimission@jpl.nasa.gov. We'll highlight some of the creations on this page. See examples and details at: saturn.jpl.nasa.gov/mission/cassiniinspires/
Our Dawn mission has found evidence for organic material on Ceres, a dwarf planet and the largest body in the main asteroid belt between Mars and Jupiter. Learn more: solarsystem.nasa.gov/news/2017/02/17/dawn-discovers-evidence-for-organic-material-on-ceres
A new device called the vortex coronagraph was recently installed inside NIRC2 (Near Infrared Camera 2) at the W.M. Keck Observatory in Hawaii and has delivered its first images, showing a ring of planet-forming dust around a star, and separately, a cool, star-like body, called a brown dwarf, lying near its companion star.
A puzzling sensor reading transformed our Cassini Saturn mission and created a new target in the search for habitable worlds beyond Earth, when on Feb. 17, 2005, Cassini made the first-ever close pass over Saturn’s moon. Since our two Voyager spacecraft made their distant flybys of Enceladus about 20 years prior, scientists had anticipated the little moon would be an interesting place to visit. Enceladus is bright white -- the most reflective object in the solar system, in fact -- and it orbits in the middle of a faint ring of dust-sized ice particles known as Saturn’s E ring. Scientists speculated ice dust was being kicked off its surface somehow. But they presumed it would be, essentially, a dead, airless ball of ice.
What Cassini saw didn't look like a frozen, airless body. Instead, it looked something like a comet that was actively emitting gas. The magnetometer detected that Saturn’s magnetic field, which envelops Enceladus, was perturbed above the moon's south pole in a way that didn't make sense for an inactive world. Could it be that the moon was actively replenishing gases it was breathing into space? Watch the video.
Our planet's southernmost active volcano reaches 12,448 feet (3,794 meters) above Ross Island in Antarctica. It's a good stand-in for a frozen alien world, the kind we want to send robots to someday. Learn more: solarsystem.nasa.gov/news/2017/02/13/descent-into-a-frozen-underworld
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Welcome to our 6th annual annual Black Hole Friday! Check out these black hole deals from the past year as you prepare to head out for a shopping spree or hunker down at home to avoid the crowds.
First things first, black holes have one basic rule: They are so incredibly dense that to escape their surface you’d have to travel faster than light. But light speed is the cosmic speed limit . . . so nothing can escape a black hole’s surface!
Some black holes form when a very large star dies in a supernova explosion and collapses into a superdense object. This is even more jam-packed than the crowds at your local mall — imagine an object 10 times more massive than the Sun squeezed into a sphere with the diameter of New York City!
Some of these collapsing stars also signal their destruction with a huge burst of gamma rays. Our Fermi Gamma-ray Space Telescope and Neil Gehrels Swift Observatory continuously seek out the signals of these gamma ray bursts — black hole birth announcements that come to us from across the universe.
There are loads of stellar mass black holes, which are just a few 10s of times the Sun’s mass, in our home galaxy alone — maybe even hundreds of millions of them! Our Neutron Star Interior Composition Explorer, or NICER for short, experiment on the International Space Station has been studying some of those relatively nearby black holes.
Near one black hole called GRS 1915+105, NICER found disk winds — fast streams of gas created by heat or pressure. Scientists are still figuring out some puzzles about these types of wind. Where do they come from, for example? And do they change the way material falls into the black hole? Every new example of these disk winds helps astronomers get closer to answering those questions.
But stellar mass black holes aren’t the only ones out there. At the center of nearly every large galaxy lies a supermassive black hole — one with the mass of millions or billions of Suns smooshed into a region no bigger than our solar system.
There’s still some debate about how these monsters form, but astronomers agree that they certainly can collide and combine when their host galaxies collide and combine. Those black holes will have a lot of gas and dust around them. As that material is pulled into the black hole it will heat up due to friction and other forces, causing it to emit light. A group of scientists wondered what light it would produce and created this mesmerizing visualization showing that most of the light produced around these two black holes is UV or X-ray light. We can’t see those wavelengths with our own eyes, but many telescopes can. Models like this could help scientists know what to look for to spot a merger.
It also turns out that these supermassive black holes are the source of some of the brightest objects in the gamma ray sky! In a type of galaxy called active galactic nuclei (also called “AGN” for short) the central black hole is surrounded by a disk of gas and dust that’s constantly falling into the black hole.
But not only that, some of those AGN have jets of energetic particles that are shooting out from near the black hole at nearly the speed of light! Scientists are studying these jets to try to understand how black holes — which pull everything in with their huge amounts of gravity — provide the energy needed to propel the particles in these jets. If that jet is pointed directly at us, it can appear super-bright in gamma rays and we call it a blazar. These blazars make up more than half of the sources our Fermi space telescope sees.
Sometimes scientists get a two-for-one kind of deal when they’re looking for black holes. Our colleagues at the IceCube Neutrino Observatory actually caught a particle from a blazar 4 billion light-years away. IceCube lies a mile under the ice in Antarctica and uses the ice itself to detect neutrinos, tiny speedy particles that weigh almost nothing and rarely interact with anything. When IceCube caught a super-high-energy neutrino and traced its origin to a specific area of the sky, they turned to the astronomical community to pinpoint the source.
Our Fermi spacecraft scans the entire sky about every three hours and for months it had observed a blazar producing more gamma rays than usual. Flaring is a common characteristic in blazars, so this didn’t attract special attention. But when the alert from IceCube came through, scientists realized the neutrino and the gamma rays came from the same patch of sky! This method of using two or more kinds of signals to learn about one event or object is called multimessenger astronomy, and it’s helping us learn a lot about the universe.
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Halloween is just around the corner. Need some chilling décor? We’ve got you – and your walls – covered with three new Galaxy of Horrors posters that showcase some of the most terrifying topics in the universe.
In the depths of the universe, the cores of two collapsed stars violently merge to release a burst of the deadliest and most powerful form of light, known as gamma rays. These beams of doom are unleashed upon their unfortunate surroundings, shining a billion trillion times brighter than the Sun for up to 30 terrifying seconds. No spaceship will shield you from their blinding destruction!
The chillingly haunted galaxy called MACS 2129-1 mysteriously stopped making stars only a few billion years after the Big Bang. It became a cosmic cemetery, illuminated by the red glow of decaying stars. Dare to enter and you might encounter the frightening corpses of exoplanets or the final death throes of once-mighty stars.
Something strange and mysterious creeps throughout the cosmos. Scientists call it dark matter. It is scattered in an intricate web that forms the skeleton of our universe. Dark matter is invisible, only revealing its presence by pushing and pulling on objects we can see. NASA’s Roman Space Telescope will investigate its secrets. What will it find?
Download the full set in English and Spanish here.
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This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole’s event horizon, beyond which no light can escape the massive object’s gravitational grip. The black hole’s powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as it skims by the black hole. You might wonder — if this Tumblr post is about invisible things, what’s with all the pictures? Even though we can’t see these things with our eyes or even our telescopes, we can still learn about them by studying how they affect their surroundings. Then, we can use what we know to make visualizations that represent our understanding.
When you think of the invisible, you might first picture something fantastical like a magic Ring or Wonder Woman’s airplane, but invisible things surround us every day. Read on to learn about seven of our favorite invisible things in the universe!
This animation illustrates what happens when an unlucky star strays too close to a monster black hole. Gravitational forces create intense tides that break the star apart into a stream of gas. The trailing part of the stream escapes the system, while the leading part swings back around, surrounding the black hole with a disk of debris. A powerful jet can also form. This cataclysmic phenomenon is called a tidal disruption event.
You know ‘em, and we love ‘em. Black holes are balls of matter packed so tight that their gravity allows nothing — not even light — to escape. Most black holes form when heavy stars collapse under their own weight, crushing their mass to a theoretical singular point of infinite density.
Although they don’t reflect or emit light, we know black holes exist because they influence the environment around them — like tugging on star orbits. Black holes distort space-time, warping the path light travels through, so scientists can also identify black holes by noticing tiny changes in star brightness or position.
A simulation of dark matter forming large-scale structure due to gravity.
What do you call something that doesn’t interact with light, has a gravitational pull, and outnumbers all the visible stuff in the universe by five times? Scientists went with “dark matter,” and they think it's the backbone of our universe’s large-scale structure. We don’t know what dark matter is — we just know it's nothing we already understand.
We know about dark matter because of its gravitational effects on galaxies and galaxy clusters — observations of how they move tell us there must be something there that we can’t see. Like black holes, we can also see light bend as dark matter’s mass warps space-time.
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.
No one knows what dark energy is either — just that it’s pushing our universe to expand faster and faster. Some potential theories include an ever-present energy, a defect in the universe’s fabric, or a flaw in our understanding of gravity.
Scientists previously thought that all the universe’s mass would gravitationally attract, slowing its expansion over time. But when they noticed distant galaxies moving away from us faster than expected, researchers knew something was beating gravity on cosmic scales. After further investigation, scientists found traces of dark energy’s influence everywhere — from large-scale structure to the background radiation that permeates the universe.
Two black holes orbit each other and generate space-time ripples called gravitational waves in this animation.
Like the ripples in a pond, the most extreme events in the universe — such as black hole mergers — send waves through the fabric of space-time. All moving masses can create gravitational waves, but they are usually so small and weak that we can only detect those caused by massive collisions. Even then they only cause infinitesimal changes in space-time by the time they reach us. Scientists use lasers, like the ground-based LIGO (Laser Interferometer Gravitational-Wave Observatory) to detect this precise change. They also watch pulsar timing, like cosmic clocks, to catch tiny timing differences caused by gravitational waves.
This animation shows gamma rays (magenta), the most energetic form of light, and elusive particles called neutrinos (gray) formed in the jet of an active galaxy far, far away. The emission traveled for about 4 billion years before reaching Earth. On Sept. 22, 2017, the IceCube Neutrino Observatory at the South Pole detected the arrival of a single high-energy neutrino. NASA’s Fermi Gamma-ray Space Telescope showed that the source was a black-hole-powered galaxy named TXS 0506+056, which at the time of the detection was producing the strongest gamma-ray activity Fermi had seen from it in a decade of observations.
This animation shows gamma rays (magenta), the most energetic form of light, and elusive particles called neutrinos (gray) formed in the jet of an active galaxy far, far away. The emission traveled for about 4 billion years before reaching Earth. On Sept. 22, 2017, the IceCube Neutrino Observatory at the South Pole detected the arrival of a single high-energy neutrino. NASA’s Fermi Gamma-ray Space Telescope showed that the source was a black-hole-powered galaxy named TXS 0506+056, which at the time of the detection was producing the strongest gamma-ray activity Fermi had seen from it in a decade of observations.
Because only gravity and the weak force affect neutrinos, they don’t easily interact with other matter — hundreds of trillions of these tiny, uncharged particles pass through you every second! Neutrinos come from unstable atom decay all around us, from nuclear reactions in the Sun to exploding stars, black holes, and even bananas.
Scientists theoretically predicted neutrinos, but we know they actually exist because, like black holes, they sometimes influence their surroundings. The National Science Foundation’s IceCube Neutrino Observatory detects when neutrinos interact with other subatomic particles in ice via the weak force.
This animation illustrates cosmic ray particles striking Earth's atmosphere and creating showers of particles.
Every day, trillions of cosmic rays pelt Earth’s atmosphere, careening in at nearly light-speed — mostly from outside our solar system. Magnetic fields knock these tiny charged particles around space until we can hardly tell where they came from, but we think high energy events like supernovae can accelerate them. Earth’s atmosphere and magnetic field protect us from cosmic rays, meaning few actually make it to the ground.
Though we don’t see the cosmic rays that make it to the ground, they tamper with equipment, showing up as radiation or as “bright” dots that come and go between pictures on some digital cameras. Cosmic rays can harm astronauts in space, so there are plenty of precautions to protect and monitor them.
The electromagnetic spectrum is the name we use when we talk about different types of light as a group. The parts of the electromagnetic spectrum, arranged from highest to lowest energy are: gamma rays, X-rays, ultraviolet light, visible light, infrared light, microwaves, and radio waves. All the parts of the electromagnetic spectrum are the same thing — radiation. Radiation is made up of a stream of photons — particles without mass that move in a wave pattern all at the same speed, the speed of light. Each photon contains a certain amount of energy.
The light that we see is a small slice of the electromagnetic spectrum, which spans many wavelengths. We frequently use different wavelengths of light — from radios to airport security scanners and telescopes.
Visible light makes it possible for many of us to perceive the universe every day, but this range of light is just 0.0035 percent of the entire spectrum. With this in mind, it seems that we live in a universe that’s more invisible than not! NASA missions like NASA's Fermi, James Webb, and Nancy Grace Roman space telescopes will continue to uncloak the cosmos and answer some of science’s most mysterious questions.
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