Asteroid Bennu, The Storyteller

The Sun is not silent. The low, pulsing hum of our star's heartbeat allows scientists to peer inside, revealing huge rivers of solar material flowing around before their eyes — er, ears.

Data from ESA (European Space Agency) and NASA’s Solar and Heliospheric Observatory (SOHO), sonified by the Stanford Experimental Physics Lab, captures the Sun’s natural vibrations and reveals what can’t be seen with the naked eye.

In this audiogram, our heliophysicist Alex Young explains how this simple sound connects us with the Sun and all the other stars in the universe.

This piece features low frequency sounds of the Sun. For the best listening experience, listen to this story with headphones. 🎧 

Read more: https://go.nasa.gov/2LMW42o

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

For Earth Day, we’re inviting you to take a moment to celebrate our wonderful water world, Earth. As far as we know, our Blue Marble is the only place in the universe with life, and that life depends on water. Snap a photo of yourself outside and tag it #GlobalSelfie – bonus points if your selfie features your favorite body of water! http://go.nasa.gov/3xFt0H0

Make sure to follow us on Tumblr for your regular dose of space!

9 Ocean Facts You Likely Don’t Know, but Should

Earth is a place dominated by water, mainly oceans. It’s also a place our researchers study to understand life. Trillions of gallons of water flow freely across the surface of our blue-green planet. Ocean’s vibrant ecosystems impact our lives in many ways. 

In celebration of World Oceans Day, here are a few things you might not know about these complex waterways.

1. Why is the ocean blue? 

The way light is absorbed and scattered throughout the ocean determines which colors it takes on. Red, orange, yellow,and green light are absorbed quickly beneath the surface, leaving blue light to be scattered and reflected back. This causes us to see various blue and violet hues.

2. Want a good fishing spot? 

Follow the phytoplankton! These small plant-like organisms are the beginning of the food web for most of the ocean. As phytoplankton grow and multiply, they are eaten by zooplankton, small fish and other animals. Larger animals then eat the smaller ones. The fishing industry identifies good spots by using ocean color images to locate areas rich in phytoplankton. Phytoplankton, as revealed by ocean color, frequently show scientists where ocean currents provide nutrients for plant growth.

3. The ocean is many colors. 

When we look at the ocean from space, we see many different shades of blue. Using instruments that are more sensitive than the human eye, we can measure carefully the fantastic array of colors of the ocean. Different colors may reveal the presence and amount of phytoplankton, sediments and dissolved organic matter.

4. The ocean can be a dark place. 

About 70 percent of the planet is ocean, with an average depth of more than 12,400 feet. Given that light doesn’t penetrate much deeper than 330 feet below the water’s surface (in the clearest water), most of our planet is in a perpetual state of darkness. Although dark, this part of the ocean still supports many forms of life, some of which are fed by sinking phytoplankton. 

5. We study all aspects of ocean life. 

Instruments on satellites in space, hundreds of kilometers above us, can measure many things about the sea: surface winds, sea surface temperature, water color, wave height, and height of the ocean surface.

6. In a gallon of average sea water, there is about 1/2 cup of salt. 

The amount of salt varies depending on location. The Atlantic Ocean is saltier than the Pacific Ocean, for instance. Most of the salt in the ocean is the same kind of salt we put on our food: sodium chloride.

7. A single drop of sea water is teeming with life.  

It will most likely have millions (yes, millions!) of bacteria and viruses, thousands of phytoplankton cells, and even some fish eggs, baby crabs, and small worms. 

8. Where does Earth store freshwater? 

Just 3.5 percent of Earth’s water is fresh—that is, with few salts in it. You can find Earth’s freshwater in our lakes, rivers, and streams, but don’t forget groundwater and glaciers. Over 68 percent of Earth’s freshwater is locked up in ice and glaciers. And another 30 percent is in groundwater. 

9. Phytoplankton are the “lungs of the ocean”.

Just like forests are considered the “lungs of the earth”, phytoplankton is known for providing the same service in the ocean! They consume carbon dioxide, dissolved in the sunlit portion of the ocean, and produce about half of the world’s oxygen. 

Want to learn more about how we study the ocean? Follow @NASAEarth on twitter.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.  

Protecting our Home Planet 🌎

Did you ever wonder how we spots asteroids that may be getting too close to Earth for comfort? Wonder no more. Our Planetary Defense Coordination Office does just that. Thanks to a variety of ground and space based telescopes, we’re able to detect potentially hazardous objects so we can prepare for the unlikely threat against our planet. 

What is a near-Earth object?

Near-Earth objects (NEOs) are asteroids and comets that orbit the Sun, but their orbits bring them into Earth’s neighborhood – within 30 million miles of Earth’s orbit.

These objects are relatively unchanged remnant debris from the solar system’s formation some 4.6 billion years ago. Most of the rocky asteroids originally formed in the warmer inner solar system between the orbits of Mars and Jupiter, while comets, composed mostly of water ice with embedded dust particles, formed in the cold outer solar system.

Who searches for near-Earth objects?

Our Near-Earth Object (NEO) Observations Program finds, tracks and monitors near-Earth asteroids and comets. Astronomers supported by the program use telescopes to follow up the discoveries to make additional measurements, as do many observatories all over the world. The Center for Near-Earth Object Studies, based at our Jet Propulsion Laboratory, also uses these data to calculate high-precision orbits for all known near-Earth objects and predict future close approaches by them to Earth, as well as the potential for any future impacts.

How do we calculate the orbit of a near-Earth object?

Scientists determine the orbit of an asteroid by comparing measurements of its position as it moves across the sky to the predictions of a computer model of its orbit around the Sun. The more observations that are used and the longer the period over which those observations are made, the more accurate the calculated orbit and the predictions that can be made from it.

How many near-Earth objects have been discovered so far?

At the start of 2019, the number of discovered NEOs totaled more than 19,000, and it has since surpassed 20,000. An average of 30 new discoveries are added each week. More than 95 percent of these objects were discovered by NASA-funded surveys since 1998, when we initially established its NEO Observations Program and began tracking and cataloguing them.

Currently the risk of an asteroid striking Earth is exceedingly low, but we are constantly monitoring our cosmic neighborhood. Have more questions? Visit our Planetary Defense page to explore how we keep track of near-Earth objects. 

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

NASA Technology in Your Life

How does NASA technology benefit life on Earth? It probably has an impact in more ways than you think! Since 1976, our Spinoff program has profiled nearly 2,000 space technologies that have transformed into commercial products and services. In celebration of Spinoff’s 40th year of publication, we’ve assembled a collection of spinoffs that have had the greatest impact on Earth. 

Take a look and see how many you utilize on a regular basis:

Digital Image Sensors

Whether you take pictures and videos with a DSLR camera or a cell phone, or even capture action on the go with a device like a GoPro Hero, you’re using NASA technology. The CMOS active pixel sensor in most digital image- capturing devices was invented when we needed to miniaturize cameras for interplanetary missions. This technology is also widely used in medical imaging and dental X-ray devices.

Enriched Baby Formula

While developing life support for Mars missions, NASA-funded researchers discovered a natural source for an omega-3 fatty acid previously found primarily in breast milk that plays a key role in infant development. The ingredient has since been added to more than 90% of infant formula on the market and is helping babies worldwide develop healthy brains, eyes and hearts.

NASTRAN Software

NASTRAN is a software developed by our engineers that performs structural analysis in the 1960s. Still popular today, it’s been used to help design everything from airplanes and cars to nuclear reactors and even Disney’s Space Mountain roller coaster.

Food Safety Standards

Looking to ensure the absolute safety of prepackaged foods for spaceflight, we partnered with the Pillsbury Company to create a new, systematic approach to quality control. Now known as Hazard Analysis and Critical Control Points (HACCP), the method has become an industry standard that benefits consumers worldwide by keeping food free from a wide range of potential chemical, physical and biological hazards.

Neutral Body Posture Specifications

What form does the human body naturally assume when all physical influences, including the pull of gravity, stop affecting it? We conducted research to find out using Skylab, America’s first space station, and later published specifications for what it called neutral body posture. The study has informed seat designs in everything from airplanes and office chairs to several models of Nissan automobiles.

Advanced Water Filtration

We recently discovered unexpected sources of water on the moon and Mars, but even so, space remains a desert for human explorers, and every drop must be recycled and reused. A nano filter devised to purify water in orbit is currently at work on Earth, in devices that supply water to remote villages as well as in a water bottle that lets hikers and adventurers stay hydrated using streams and lakes.

Swimsuit Designs

Wind-tunnel testing at our Langley Research Center played a key role in the development of Speedo’s LZR Racer swimsuit, proving which materials and seams best reduced drag as a swimmer cuts through the water. The swimsuit made a splash during its Olympic debut in 2008, as nearly every medal winner and world-record breaker wore the suit.

Air Purifier

When plants grow, they release a gas called ethylene that accelerates decay, hastening the wilting of flowers and the ripening of fruits and vegetables. Air circulation on Earth keeps the fumes from building up, but in the hermetically sealed environment of a spacecraft, ethylene poses a real challenge to the would-be space farmers. We funded the development of an ethylene scrubber for the International Space Station that has subsequently proved capable of purifying air on Earth from all kinds of pathogens and particulates. Grocery stores use it to keep produce fresh longer. It’s also been marketed for home use and has even been embraced by winemakers, who employ the scrubber to keep aging wine in barrels free from mold, mildew and musty odors.

Scratch-Resistant, UV-Reflective Lenses

Some of the earliest research into effective scratch-resistant coatings for prescription and sunglass lenses drew from work done at Ames Research Center on coatings for astronaut helmet visors and plastic membranes used in water purification systems. In the 1980s, we developed sunlight-filtering lenses to provide eye protection and enhance colors, and these lenses have found their way into sunglasses, ski goggles and safety masks for welders.

Dustbuster

An Apollo-era partnership with Black & Decker to build battery-operated tools for moon exploration and sample collection led to the development of a line of consumer, medical and industrial hand-held cordless tools. This includes the popular Dustbuster cordless vacuum.

To see even more of our spinoff technologies, visit: http://www.nasa.gov/offices/oct/40-years-of-nasa-spinoff

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Pi Guides the Way

It may be irrational but pi plays an important role in the everyday work of scientists at NASA. 

What Is Pi ?

Pi is the ratio of a circle’s circumference to its diameter. It is also an irrational number, meaning its decimal representation never ends and it never repeats. Pi has been calculated to more than one trillion digits, 

Why March 14?

March 14 marks the yearly celebration of the mathematical constant pi. More than just a number for mathematicians, pi has all sorts of applications in the real world, including on our missions. And as a holiday that encourages more than a little creativity – whether it’s making pi-themed pies or reciting from memory as many of the never-ending decimals of pi as possible (the record is 70,030 digits).

While 3.14 is often a precise enough approximation, hence the celebration occurring on March 14, or 3/14 (when written in standard U.S.  month/day format), the first known celebration occurred in 1988, and in 2009, the U.S. House of Representatives passed a resolution designating March 14 as Pi Day and encouraging teachers and students to celebrate the day with activities that teach students about pi.

5 Ways We Use Pi at NASA

Below are some ways scientists and engineers used pi.

Keeping Spacecraft Chugging Along

Propulsion engineers use pi to determine the volume and surface area of propellant tanks. It’s how they size tanks and determine liquid propellant volume to keep spacecraft going and making new discoveries. 

Getting New Perspectives on Saturn

A technique called pi transfer uses the gravity of Titan’s moon, Titan, to alter the orbit of the Cassini spacecraft so it can obtain different perspectives of the ringed planet.

Learning the Composition of Asteroids

Using pi and the asteroid’s mass, scientists can calculate the density of an asteroid and learn what it’s made of--ice, iron, rock, etc.

Measuring Craters

knowing the circumference, diameter and surface area of a crater can tell scientists a lot about the asteroid or meteor that may have carved it out.

Determining the Size of Exoplanets

Exoplanets are planets that orbit suns other than our own and scientists use pi to search for them. The first step is determining how much the light curve of a planet’s sun dims when a suspected planets passes in front of it.

Want to learn more about Pi? Visit us on Pinterest at: https://www.pinterest.com/nasa/pi-day/

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

How to Safely Watch the Aug. 21 Solar Eclipse

On Aug. 21, 2017, a solar eclipse will be visible in North America. Throughout the continent, the Moon will cover part – or all – of the Sun’s super-bright face for part of the day.

Since it’s never safe to look at the partially eclipsed or uneclipsed Sun, everyone who plans to watch the eclipse needs a plan to watch it safely. One of the easiest ways to watch an eclipse is solar viewing glasses – but there are a few things to check to make sure your glasses are safe:

 Glasses should have an ISO 12312-2 certification

They should also have the manufacturer’s name and address, and you can check if the manufacturer has been verified by the American Astronomical Society

Make sure they have no scratches or damage

To use solar viewing glasses, make sure you put them on before looking up at the Sun, and look away before you remove them. Proper solar viewing glasses are extremely dark, and the landscape around you will be totally black when you put them on – all you should see is the Sun (and maybe some types of extremely bright lights if you have them nearby).

Never use solar viewing glasses while looking through a telescope, binoculars, camera viewfinder, or any other optical device. The concentrated solar rays will damage the filter and enter your eyes, causing serious injury. But you can use solar viewing glasses on top of your regular eyeglasses, if you use them!

If you don’t have solar viewing glasses, there are still ways to watch, like making your own pinhole projector. You can make a handheld box projector with just a few simple supplies – or simply hold any object with a small hole (like a piece of cardstock with a pinhole, or even a colander) above a piece of paper on the ground to project tiny images of the Sun.

Of course, you can also watch the entire eclipse online with us. Tune into nasa.gov/eclipselive starting at noon ET on Aug. 21! 

For people in the path of totality, there will be a few brief moments when it is safe to look directly at the eclipse. Only once the Moon has completely covered the Sun and there is no light shining through is it safe to look at the eclipse. Make sure you put your eclipse glasses back on or return to indirect viewing before the first flash of sunlight appears around the Moon’s edge.

You can look up the length of the total eclipse in your area to help you set a time for the appropriate length of time. Remember – this only applies to people within the path of totality.

Everyone else will need to use eclipse glasses or indirect viewing throughout the entire eclipse!

Photographing the Eclipse

Whether you’re an amateur photographer or a selfie master, try out these tips for photographing the eclipse.  

#1 — Safety first: Make sure you have the required solar filter to protect your camera.

#2 — Any camera is a good camera, whether it’s a high-end DSLR or a camera phone – a good eye and vision for the image you want to create is most important.

#3 — Look up, down, and all around. As the Moon slips in front of the Sun, the landscape will be bathed in long shadows, creating eerie lighting across the landscape. Light filtering through the overlapping leaves of trees, which creates natural pinholes, will also project mini eclipse replicas on the ground. Everywhere you can point your camera can yield exceptional imagery, so be sure to compose some wide-angle photos that can capture your eclipse experience.

#4 — Practice: Be sure you know the capabilities of your camera before Eclipse Day. Most cameras, and even many camera phones, have adjustable exposures, which can help you darken or lighten your image during the tricky eclipse lighting. Make sure you know how to manually focus the camera for crisp shots.

#5 —Upload your eclipse images to NASA’s Eclipse Flickr Gallery and relive the eclipse through other peoples’ images.

Learn all about the Aug. 21 eclipse at eclipse2017.nasa.gov, and follow @NASASun on Twitter and NASA Sun Science on Facebook for more. Watch the eclipse through the eyes of NASA at nasa.gov/eclipselive starting at 12 PM ET on Aug. 21.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Spooky Sounds from Across the Solar System

Soaring to the depths of our universe, gallant spacecraft roam the cosmos, snapping images of celestial wonders. Some spacecraft have instruments capable of capturing radio emissions. When scientists convert these to sound waves, the results are eerie to hear.

In time for Halloween, we've put together a compilation of elusive "sounds" of howling planets and whistling helium that is sure to make your skin crawl.

Listen to a few here and visit our Soundcloud for more spooky sounds. 

Cassini Ring Crossing

This eerie audio represents data collected by our Cassini spacecraft, as it crossed through the gap between Saturn and its rings on April 26, 2017, during the first dive of the mission's Grand Finale. The instrument is able to record ring particles striking the spacecraft in its data. In the data from this dive, there is virtually no detectable peak in pops and cracks that represent ring particles striking the spacecraft. The lack of discernible pops and cracks indicates the region is largely free of small particles. 

Voyager Tsunami Waves in Interstellar Space 

Listen to this howling audio from our Voyager 1 spacecraft. Voyager 1 has experienced three "tsunami waves" in interstellar space. This kind of wave occurs as a result of a coronal mass ejection erupting from the Sun. The most recent tsunami wave that Voyager experienced began in February 2014, and may still be going. Listen to how these waves cause surrounding ionized matter to ring like a bell.

Voyager Sounds of Interstellar Space

Our Voyager 1 spacecraft captured these high-pitched, spooky sounds of interstellar space from October to November 2012 and April to May 2013.

The soundtrack reproduces the amplitude and frequency of the plasma waves as "heard" by Voyager 1. The waves detected by the instrument antennas can be simply amplified and played through a speaker. These frequencies are within the range heard by human ears.

When scientists extrapolated this line even further back in time (not shown), they deduced that Voyager 1 first encountered interstellar plasma in August 2012.

Plasma Sounds at Jupiter

Ominous sounds of plasma! Our Juno spacecraft has observed plasma wave signals from Jupiter’s ionosphere. The results in this video show an increasing plasma density as Juno descended into Jupiter’s ionosphere during its close pass by Jupiter on February 2, 2017.  

Roar of Jupiter

Juno's Waves instrument recorded this supernatural sounding encounter with the bow shock over the course of about two hours on June 24, 2016. "Bow shock" is where the supersonic solar wind is heated and slowed by Jupiter's magnetosphere. It is analogous to a sonic boom on Earth. The next day, June 25, 2016, the Waves instrument witnessed the crossing of the magnetopause. "Trapped continuum radiation" refers to waves trapped in a low-density cavity in Jupiter's magnetosphere.

Visit the NASA Soundcloud for more spooky space sounds: https://soundcloud.com/nasa/sets/spookyspacesounds

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.

Astronaut in the house!

Air Force Colonel and NASA Astronaut Nick Hague is back from his seven month stay aboard the space station and ready to answer your questions in today's Tumblr Answer Time!

Let's get started.

Five Famous Pulsars from the Past 50 Years

Early astronomers faced an obstacle: their technology. These great minds only had access to telescopes that revealed celestial bodies shining in visible light. Later, with the development of new detectors, scientists opened their eyes to other types of light like radio waves and X-rays. They realized cosmic objects look very different when viewed in these additional wavelengths. Pulsars — rapidly spinning stellar corpses that appear to pulse at us — are a perfect example.

The first pulsar was observed 50 years ago on August 6, 1967, using radio waves, but since then we have studied them in nearly all wavelengths of light, including X-rays and gamma rays.

Typical Pulsar

Most pulsars form when a star — between 8 and 20 times the mass of our sun — runs out of fuel and its core collapses into a super dense and compact object: a neutron star. 

These neutron stars are about the size of a city and can rotate slowly or quite quickly, spinning anywhere from once every few hours to hundreds of times per second. As they whirl, they emit beams of light that appear to blink at us from space.

First Pulsar

One day five decades ago, a graduate student at the University of Cambridge, England, named Jocelyn Bell was poring over the data from her radio telescope - 120 meters of paper recordings.

Image Credit: Sumit Sijher

She noticed some unusual markings, which she called “scruff,” indicating a mysterious object (simulated above) that flashed without fail every 1.33730 seconds. This was the very first pulsar discovered, known today as PSR B1919+21.

Best Known Pulsar

Before long, we realized pulsars were far more complicated than first meets the eye — they produce many kinds of light, not only radio waves. Take our galaxy’s Crab Nebula, just 6,500 light years away and somewhat of a local celebrity. It formed after a supernova explosion, which crushed the parent star's core into a neutron star. 

The resulting pulsar, nestled inside the nebula that resulted from the supernova explosion, is among the most well-studied objects in our cosmos. It’s pictured above in X-ray light, but it shines across almost the entire electromagnetic spectrum, from radio waves to gamma rays.

Brightest Gamma-ray Pulsar

Speaking of gamma rays, in 2015 our Fermi Gamma-ray Space Telescope discovered the first pulsar beyond our own galaxy capable of producing such high-energy emissions. 

Located in the Tarantula Nebula 163,000 light-years away, PSR J0540-6919 gleams nearly 20 times brighter in gamma-rays than the pulsar embedded in the Crab Nebula.

Dual Personality Pulsar

No two pulsars are exactly alike, and in 2013 an especially fast-spinning one had an identity crisis. A fleet of orbiting X-ray telescopes, including our Swift and Chandra observatories, caught IGR J18245-2452 as it alternated between generating X-rays and radio waves. 

Scientists suspect these radical changes could be due to the rise and fall of gas streaming onto the pulsar from its companion star.

Transformer Pulsar

This just goes to show that pulsars are easily influenced by their surroundings. That same year, our Fermi Gamma Ray Space Telescope uncovered another pulsar, PSR J1023+0038, in the act of a major transformation — also under the influence of its nearby companion star. 

The radio beacon disappeared and the pulsar brightened fivefold in gamma rays, as if someone had flipped a switch to increase the energy of the system. 

NICER Mission

Our Neutron star Interior Composition Explorer (NICER) mission, launched this past June, will study pulsars like those above using X-ray measurements.

With NICER’s help, scientists will be able to gaze even deeper into the cores of these dense and mysterious entities.

For more information about NICER, visit https://www.nasa.gov/nicer

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com