Today, we and the National Science Foundation (NSF) announced the detection of light and a high-energy cosmic particle that both came from near a black hole billions of trillions of miles from Earth. This discovery is a big step forward in the field of multimessenger astronomy.
People learn about different objects through their senses: sight, touch, taste, hearing and smell. Similarly, multimessenger astronomy allows us to study the same astronomical object or event through a variety of “messengers,” which include light of all wavelengths, cosmic ray particles, gravitational waves, and neutrinos — speedy tiny particles that weigh almost nothing and rarely interact with anything. By receiving and combining different pieces of information from these different messengers, we can learn much more about these objects and events than we would from just one.
Much of what we know about the universe comes just from different wavelengths of light. We study the rotations of galaxies through radio waves and visible light, investigate the eating habits of black holes through X-rays and gamma rays, and peer into dusty star-forming regions through infrared light.
The Fermi Gamma-ray Space Telescope, which recently turned 10, studies the universe by detecting gamma rays — the highest-energy form of light. This allows us to investigate some of the most extreme objects in the universe.
Last fall, Fermi was involved in another multimessenger finding — the very first detection of light and gravitational waves from the same source, two merging neutron stars. In that instance, light and gravitational waves were the messengers that gave us a better understanding of the neutron stars and their explosive merger into a black hole.
Fermi has also advanced our understanding of blazars, which are galaxies with supermassive black holes at their centers. Black holes are famous for drawing material into them. But with blazars, some material near the black hole shoots outward in a pair of fast-moving jets. With blazars, one of those jets points directly at us!
Today’s announcement combines another pair of messengers. The IceCube Neutrino Observatory lies a mile under the ice in Antarctica and uses the ice itself to detect neutrinos. When IceCube caught a super-high-energy neutrino and traced its origin to a specific area of the sky, they alerted the astronomical community.
Fermi completes a scan of the entire sky about every three hours, monitoring thousands of blazars among all the bright gamma-ray sources it sees. For months it had observed a blazar producing more gamma rays than usual. Flaring is a common characteristic in blazars, so this did not attract special attention. But when the alert from IceCube came through about a neutrino coming from that same patch of sky, and the Fermi data were analyzed, this flare became a big deal!
IceCube, Fermi, and followup observations all link this neutrino to a blazar called TXS 0506+056. This event connects a neutrino to a supermassive black hole for the very first time.
Why is this such a big deal? And why haven’t we done it before? Detecting a neutrino is hard since it doesn’t interact easily with matter and can travel unaffected great distances through the universe. Neutrinos are passing through you right now and you can’t even feel a thing!
The neat thing about this discovery — and multimessenger astronomy in general — is how much more we can learn by combining observations. This blazar/neutrino connection, for example, tells us that it was protons being accelerated by the blazar’s jet. Our study of blazars, neutrinos, and other objects and events in the universe will continue with many more exciting multimessenger discoveries to come in the future.
Want to know more? Read the story HERE.
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Saturn is sometimes called “The Jewel of the Solar System.” It is a planet that is nothing like our own. Humans have been gazing up at Saturn for a long time. They have been wondering about it for thousands of years.
Here are some fun facts about the Ringed Planet.
Saturn is huge. It is the second largest planet in our Solar System. Jupiter is the only planet that is bigger.
The rings are huge but thin. The main rings could almost go from Earth to the moon. Yet, they are less than a kilometer thick.
Four spacecraft have visited Saturn: Pioneer 11, Voyager 1 and 2, and the Cassini-Huygens mission have all studied the planet.
Saturn has oval-shaped storms similar to Jupiter’s: The region around its north pole has a hexagonal-shaped pattern of clouds. Scientists think this may be a wave pattern in the upper clouds. The planet also has a vortex over its south pole that resembles a hurricane-like storm.
Saturn is made mostly of hydrogen and helium: It exists in layers that get denser farther into the planet. Eventually, deep inside, the hydrogen becomes metallic. At the core lies a hot interior. (click the image for a better resolution).
Saturn has 62 moons: Some of these are large, like Titan, the second largest moon in the Solar System. But most are tiny – just a few km across, and they have no official names. In fact, the last few were discovered by NASA’s Cassini orbiter just a few years ago. More will probably be discovered in the coming years.
Saturn orbits the Sun once every 29.4 Earth years: Its slow movement against the backdrop of stars earned it the nickname of “Lubadsagush” from the ancient Assyrians. The name means “oldest of the old”.
In Saturn there is aurora: Photographic composition made by the Hubble Space Telescope showing the occurrence of aurora in the southern hemisphere of Saturn at intervals of two days.The aurora is visible only in the ultraviolet.
Saturn spins on its axis very fast. A day on Saturn is 10 hours and 14 minutes.
You can see Saturn with your own eyes: Saturn appears as one of the 5 planets visible with the unaided eye. If Saturn is in the sky at night, you can head outside and see it. To see the rings and the ball of the planet itself, you’ll want to peer through a telescope. But you can amaze your friends and family by pointing out that bright star in the sky, and let them know they’re looking at Saturn.
sources: nasa.gov, universetoday.com and solarsystem.nasa.gov
This artist’s illustration shows the region around a supermassive black hole after a star wandered too close and was ripped apart by extreme gravitational forces. Some of the remains of the star are pulled into an X-ray-bright disk where they circle the black hole before passing over the “event horizon,” the boundary beyond which nothing, including light, can escape. The elongated spot depicts a bright region in the disk, which causes a regular variation in the X-ray brightness of the source, allowing the spin rate of the black hole to be estimated. The curved region in the upper left shows where light from the other side of the disk has been curved over the top of the black hole.
This event was first detected by a network of optical telescopes called the All-Sky Automated Survey for Supernovae (ASASSN) in November 2014. Astronomers dubbed the new source ASASSN14-li and traced the bright flash of light to a galaxy about 290 million light years from Earth. They also identified it as a “tidal disruption” event, where one cosmic object is shredded by another through gravity.
Astronomers then used other telescopes including a flotilla of high-energy telescopes in space — NASA’s Chandra X-ray Observatory, ESA’s XMM-Newton and NASA’s Neil Gehrels Swift observatory — to study the X-rays emitted as the remains of a star swirled toward the black hole at the center of the galaxy.
The tidal disruption in ASASSN-14li is intriguing because it allowed astronomers to measure the spin rate of the black hole. A black hole has two fundamental properties: mass and spin. While it has been relatively easy for astronomers to determine the mass of black holes, it has been much more difficult to get accurate measurements of their spins.
This debris from the shredded star gave astronomers an avenue to get a direct measure of the black hole’s spin in ASASSN-14li. They found that the event horizon around this black hole is about 300 times the diameter of the Earth, yet rotates once every two minutes (compared to the 24 hours it takes to complete one rotation). This means that the black hole is spinning at least half as fast as the speed of light.
Scientists have determined spin rates for some stellar-mass black holes (those that typically weigh between 5 and 30 solar masses) in our Milky Way galaxy by observing rapid and regular variations in their X-ray brightness. A few supermassive black holes have shown similar variations, but they were only observed to repeat over a few cycles, rather than the 300,000 cycles seen for ASASSN-14li. With only a few cycles, the association of the variations with the spin of the black hole is not secure.
These results will likely encourage astronomers to observe future tidal disruption events for long durations to look for similar, regular variations in their X-ray brightness. source
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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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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So you think you found an exoplanet – a planet around another star? It’s not as simple as pointing a telescope to the sky and looking for a planet that waves back. Scientists gather many observations and carefully analyze their data before they can be even somewhat sure that they’ve discovered new worlds.
Here are 10 things to know about finding and confirming exoplanets.
This is an illustration of the different elements in our exoplanet program, including ground-based observatories, like the W. M. Keck Observatory, and space-based observatories like Hubble, Spitzer, Kepler, TESS, James Webb Space Telescope, WFIRST and future missions.
The vast majority of planets around other stars have been found through the transit method so far. This technique involves monitoring the amount of light that a star gives off over time, and looking for dips in brightness that may indicate an orbiting planet passing in front of the star.
We have two specialized exoplanet-hunting telescopes scanning the sky for new planets right now – Kepler and the Transiting Exoplanet Survey Satellite (TESS) – and they both work this way. Other methods of finding exoplanets include radial velocity (looking for a “wobble” in a star’s position caused by a planet’s gravity), direct imaging (blocking the light of the star to see the planet) and microlensing (watching for events where a star passes in front of another star, and the gravity of the first star acts as a lens).
Here’s more about finding exoplanets.
To find a planet, scientists need to get data from telescopes, whether those telescopes are in space or on the ground. But telescopes don’t capture photos of planets with nametags. Instead, telescopes designed for the transit method show us how brightly thousands of stars are shining over time. TESS, which launched in April and just began collecting science data, beams its stellar observations back to Earth through our Deep Space Network, and then scientists get to work.
Researchers combing through TESS data are looking for those transit events that could indicate planets around other stars. If the star’s light lessens by the same amount on a regular basis – for example, every 10 days – this may indicate a planet with an orbital period (or “year”) of 10 days. The standard requirement for planet candidates from TESS is at least two transits – that is, two equal dips in brightness from the same star.
Not all dips in a star’s brightness are caused by transiting planets. There may be another object – such as a companion star, a group of asteroids, a cloud of dust or a failed star called a brown dwarf, that makes a regular trip around the target star. There could also be something funky going on with the telescope’s behavior, how it delivered the data, or other “artifacts” in data that just aren’t planets. Scientists must rule out all non-planet options to the best of their ability before moving forward.
Finding the same planet candidate using two different techniques is a strong sign that the planet exists, and is the standard for “confirming” a planet. That’s why a vast network of ground-based telescopes will be looking for the same planet candidates that TESS discovers. It is also possible that TESS will spot a planet candidate already detected by another telescope in the past. With these combined observations, the planet could then be confirmed. The first planet TESS discovered, Pi Mensae c, orbits a star previously observed with the radial-velocity method on the ground. Scientists compared the TESS data and the radial-velocity data from that star to confirm the presence of planet “c.”
Scientists using the radial-velocity detection method see a star’s wobble caused by a planet’s gravity, and can rule out other kinds of objects such as companion stars. Radial-velocity detection also allows scientists to calculate the mass of the planet.
Other space telescopes may also be used to help confirm exoplanets, characterize them and even discover additional planets around the same stars. If the planet is detected by the same method, but by two different telescopes, and has received enough scrutiny that the scientists are more than 99 percent sure it’s a planet, it is said to be “validated” instead of “confirmed.”
After thoroughly analyzing the data, and running tests to make sure that their result still looks like the signature of a planet, scientists write a formal paper describing their findings. Using the transit method, they can also report the size of the planet. The planet’s radius is related to how much light it blocks from the star, as well as the size of the star itself. The scientists then submit the study to a journal.
Scientific journals have a rigorous peer review process. This means scientific experts not involved in the study review it and make sure the findings look sound. The peer-reviewers may have questions or suggestions for the scientists. When everyone agrees on a version of the study, it gets published.
When the study is published, scientists can officially say they have found a new planet. This may still not be the end of the story, however. For example, the TRAPPIST telescope in Chile first thought they had discovered three Earth-size planets in the TRAPPIST-1 system. When our Spitzer Space Telescope and other ground-based telescopes followed up, they found that one of the original reported planets (the original TRAPPIST-1d) did not exist, but they discovered five others –bringing the total up to seven wondrous rocky worlds.
Confirmed planets get added to our official catalog. So far, Kepler has sent back the biggest bounty of confirmed exoplanets of any telescope – more than 2,600 to date. TESS, which just began its planet search, is expected to discover many thousands more. Ground-based follow-up will help determine if these planets are gaseous or rocky, and possibly more about their atmospheres. The forthcoming James Webb Space Telescope will be able to take a deeper look at the atmospheres of the most interesting TESS discoveries.
Scientists sometimes even uncover planets with the help of people like you: exoplanet K2-138 was discovered through citizen scientists in Kepler’s K2 mission data. Based on surveys so far, scientists calculate that almost every star in the Milky Way should have at least one planet. That makes billions more, waiting to be found! Stay up to date with our latest discoveries using this exoplanet counter.
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‘’A God’s Eye View of the Universe’‘
Credit: SpaceRip
This winter, our scientists and engineers traveled to the world’s northernmost civilian town to launch rockets equipped with cutting-edge scientific instruments.
This is the beginning of a 14-month-long campaign to study a particular region of Earth’s magnetic field — which means launching near the poles. What’s it like to launch a science rocket in these extreme conditions?
Our planet is protected by a natural magnetic field that deflects most of the particles that flow out from the Sun — the solar wind — away from our atmosphere. But near the north and south poles, two oddities in Earth’s magnetic field funnel these solar particles directly into our atmosphere. These regions are the polar cusps, and it turns out they’re the ideal spot for studying how our atmosphere interacts with space.
The scientists of the Grand Challenge Initiative — Cusp are using sounding rockets to do their research. Sounding rockets are suborbital rockets that launch to a few hundred miles in altitude, spending a few minutes in space before falling back to Earth. That means sounding rockets can carry sensitive instruments above our atmosphere to study the Sun, other stars and even distant galaxies.
They also fly directly through some of the most interesting regions of Earth’s atmosphere, and that’s what scientists are taking advantage of for their Grand Challenge experiments.
One of the ideal rocket ranges for cusp science is in Ny-Ålesund, Svalbard, off the coast of Norway and within the Arctic circle. Because of its far northward position, each morning Svalbard passes directly under Earth’s magnetic cusp.
But launching in this extreme, remote environment puts another set of challenges on the mission teams. These launches need to happen during the winter, when Svalbard experiences 24/7 darkness because of Earth’s axial tilt. The launch teams can go months without seeing the Sun.
Like for all rocket launches, the science teams have to wait for the right weather conditions to launch. Because they’re studying upper atmospheric processes, some of these teams also have to wait for other science conditions, like active auroras. Auroras are created when charged particles collide with Earth’s atmosphere — often triggered by solar storms or changes in the solar wind — and they’re related to many of the upper-atmospheric processes that scientists want to study near the magnetic cusp.
But even before launch, the extreme conditions make launching rockets a tricky business — it’s so cold that the rockets must be encased in styrofoam before launch to protect them from the low temperatures and potential precipitation.
When all is finally ready, an alarm sounds throughout the town of Ny-Ålesund to alert residents to the impending launch. And then it’s up, up and away! This photo shows the launch of the twin VISIONS-2 sounding rockets on Dec. 7, 2018 from Ny-Ålesund.
These rockets are designed to break up during flight — so after launch comes clean-up. The launch teams track where debris lands so that they can retrieve the pieces later.
The next launch of the Grand Challenge Initiative is AZURE, launching from Andøya Space Center in Norway in April 2019.
For even more about what it’s like to launch science rockets in extreme conditions, check out one scientist’s notes from the field: https://go.nasa.gov/2QzyjR4
For updates on the Grand Challenge Initiative and other sounding rocket flights, visit nasa.gov/soundingrockets or follow along with NASA Wallops and NASA heliophysics on Twitter and Facebook.
@NASA_Wallops | NASA’s Wallops Flight Facility | @NASASun | NASA Sun Science
“I’d like somebody to finally acknowledge and admit that showing balls on a bed sheet doesn’t cut it as a picture of reality.”
Okay, I admit it: visualizing General Relativity as balls on a bedsheet doesn’t make a whole lot of sense. For one, if this is what gravity is supposed to be, what pulls the balls “down” onto the bedsheet? For another, if space is three dimensional, why are we talking about a 2D “fabric” of space? And for another, why do these lines curve away from the mass, rather than towards it?
It’s true: this visualization of General Relativity is highly flawed. But, believe it or not, all visualizations of General Relativity inherently have similar flaws. The reason is that space itself is not an observable thing! In Einstein’s theory, General Relativity provides the link between the matter and energy in the Universe, which determines the geometric curvature of spacetime, and how the rest of the matter and energy in the Universe moves in response to that. In this Universe, we can only measure matter and energy, not space itself. We can visualize it how we like, but all visualizations are inherently flawed.
Come get the story of how to make as much sense as possible out of the Universe we actually have.
Maybe it’s time to turn your attention back to yourself and to your own self-care. Although we often brush it aside, self-care is not optional if you want to be happy and healthy.