Spread Your Cosmic Wings 🦋

Magnetospheres: How Do They Work?

The sun, Earth, and many other planets are surrounded by giant magnetic bubbles.

Space may seem empty, but it’s actually a dynamic place, dominated by invisible forces, including those created by magnetic fields.  Magnetospheres – the areas around planets and stars dominated by their magnetic fields – are found throughout our solar system. They deflect high-energy, charged particles called cosmic rays that are mostly spewed out by the sun, but can also come from interstellar space. Along with atmospheres, they help protect the planets’ surfaces from this harmful radiation.

It’s possible that Earth’s protective magnetosphere was essential for the development of conditions friendly to life, so finding magnetospheres around other planets is a big step toward determining if they could support life.

But not all magnetospheres are created equal – even in our own backyard, not all planets in our solar system have a magnetic field, and the ones we have observed are all surprisingly different.

Earth’s magnetosphere is created by the constantly moving molten metal inside Earth. This invisible “force field” around our planet has an ice cream cone-like shape, with a rounded front and a long, trailing tail that faces away from the sun. The magnetosphere is shaped that way because of the constant pressure from the solar wind and magnetic fields on the sun-facing side.

Earth’s magnetosphere deflects most charged particles away from our planet – but some do become trapped in the magnetic field and create auroras when they rain down into the atmosphere.

We have several missions that study Earth’s magnetosphere – including the Magnetospheric Multiscale mission, Van Allen Probes, and Time History of Events and Macroscale Interactions during Substorms (also known as THEMIS) – along with a host of other satellites that study other aspects of the sun-Earth connection.

Mercury, with a substantial iron-rich core, has a magnetic field that is only about 1% as strong as Earth’s. It is thought that the planet’s magnetosphere is stifled by the intense solar wind, limiting its strength, although even without this effect, it still would not be as strong as Earth’s. The MESSENGER satellite orbited Mercury from 2011 to 2015, helping us understand our tiny terrestrial neighbor.

After the sun, Jupiter has by far the biggest magnetosphere in our solar system – it stretches about 12 million miles from east to west, almost 15 times the width of the sun. (Earth’s, on the other hand, could easily fit inside the sun.) Jupiter does not have a molten metal core like Earth; instead, its magnetic field is created by a core of compressed liquid metallic hydrogen.

One of Jupiter’s moons, Io, has intense volcanic activity that spews particles into Jupiter’s magnetosphere. These particles create intense radiation belts and the large auroras around Jupiter’s poles.

Ganymede, Jupiter’s largest moon, also has its own magnetic field and magnetosphere – making it the only moon with one. Its weak field, nestled in Jupiter’s enormous shell, scarcely ruffles the planet’s magnetic field.

Our Juno mission orbits inside the Jovian magnetosphere sending back observations so we can better understand this region. Previous observations have been received from Pioneers 10 and 11, Voyagers 1 and 2, Ulysses, Galileo and Cassini in their flybys and orbits around Jupiter.

Saturn’s moon Enceladus transforms the shape of its magnetosphere. Active geysers on the moon’s south pole eject oxygen and water molecules into the space around the planet. These particles, much like Io’s volcanic emissions at Jupiter, generate the auroras around the planet’s poles. Our Cassini mission studies Saturn’s magnetic field and auroras, as well as its moon Enceladus.

Uranus’ magnetosphere wasn't discovered until 1986 when data from Voyager 2’s flyby revealed weak, variable radio emissions. Uranus’ magnetic field and rotation axis are out of alignment by 59 degrees, unlike Earth’s, whose magnetic field and rotation axis differ by only 11 degrees. On top of that, the magnetic field axis does not go through the center of the planet, so the strength of the magnetic field varies dramatically across the surface. This misalignment also means that Uranus’ magnetotail – the part of the magnetosphere that trails away from the sun – is twisted into a long corkscrew.

Neptune’s magnetosphere is also tilted from its rotation axis, but only by 47. Just like on Uranus, Neptune’s magnetic field strength varies across the planet. This also means that auroras can be seen away from the planet’s poles – not just at high latitudes, like on Earth, Jupiter and Saturn.

Does Every Planet Have a Magnetosphere?

Neither Venus nor Mars have global magnetic fields, although the interaction of the solar wind with their atmospheres does produce what scientists call an “induced magnetosphere.” Around these planets, the atmosphere deflects the solar wind particles, causing the solar wind’s magnetic field to wrap around the planet in a shape similar to Earth’s magnetosphere.

What About Beyond Our Solar System?

Outside of our solar system, auroras, which indicate the presence of a magnetosphere, have been spotted on brown dwarfs – objects that are bigger than planets but smaller than stars.

There’s also evidence to suggest that some giant exoplanets have magnetospheres. As scientists now believe that Earth’s protective magnetosphere was essential for the development of conditions friendly to life, finding magnetospheres around exoplanets is a big step in finding habitable worlds.  

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Hello again👋

Welcome back to week number four of Mindful Monday, 2023. It’s great to see all y’all 🧘

If you’re into the cosmos and mindfulness, we think you’re gonna LOVE this. This week, we invite you to bask in the glow of a Uranian sunset as you turn on, tune in, and space out to relaxing music and stunning ultra-high-definition visuals of our cosmic neighborhood. 🌄

Sounds good, right? Of course, it does. Mysterious, even. You can watch even more Space Out episodes on NASA+, a new no-cost, ad-free streaming service.

Why not give it a try? Because just a few minutes this Monday morning can make all the difference to your entire week, as @nasa helps to bring mindfulness from the stars and straight to you. 

🧘WATCH: Space Out with NASA: Uranian Sunset. 12/18 at 1pm EST🧘

YouTube

Space Out with NASA: Uranian Sunset

Bask in the glow of a Uranian sunset as you turn on, tune in, and space out to relaxing music and stunning ultra-high-definition visuals of

Say hello to spiral galaxy NGC 1097 👋

About 45 million light-years away, in another corner of the cosmos, lies spiral galaxy NGC 1097. Though this Hubble Space Telescope image zooms in toward the core, the galaxy’s vast spiral arms span over 100,000 light-years as they silently sweep through space. At the heart of this galaxy lurks a black hole that is about 100 million times as massive as the Sun.

The supermassive black hole is voraciously eating up surrounding matter, which forms a doughnut-shaped ring around it. Matter that's pulled into the black hole releases powerful radiation, making the star-filled center of the galaxy even brighter. Hubble’s observations have led to the discovery that while the material that is drawn toward NGC 1097’s black hole may be doomed to die, new stars are bursting into life in the ring around it.

This sparkling spiral galaxy is especially interesting to both professional scientists and amateur astronomers. It is a popular target for supernova hunters ever since the galaxy experienced three supernovas in relatively rapid succession — just over a decade, between 1992 and 2003. Scientists are intrigued by the galaxy’s satellites — smaller “dwarf” galaxies that orbit NGC 1097 like moons. Studying this set of galaxies could reveal new information about how galaxies interact with each other and co-evolve.

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Take Your GIF Game to Cosmic Levels & React Like a NASA Astronaut!

We partnered with GIPHY to help take your GIF game to cosmic levelssss. As the Artemis generation who will witness a whole new era of space travel, we wanted make sure you could express yourself... like an astronaut!

So, if you want to show some love...

... or you’re pumped we’re half way to Friday ... 

We’ve got you covered.

Don’t miss our whole collection of astronaut reactions! 

Want to use them on your device? 

Type ‘NASAReaction’ in your device’s GIPHY keyboard... 

.... and choose your favorite! 

You can access our full collection of official NASA astronaut GIFs by visiting: https://giphy.com/nasa/reaction-pack

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This Week @ NASA

Astronauts conduct a spacewalk on the International Space Station to prepare it for future activities. Peggy Whitson became the new women’s record holder for number of spacewalks and more!

International Space Station

Work continued aboard the International Space Station. Spacewalkers Shane Kimbrough and Peggy Whitson used the station’s robotic arm to move the Pressurized Mating Adapter-3 on March 24 to move a module to accommodate U.S. commercial spacecraft carrying astronauts on future missions. They continued this work on March 30. Another spacewalk to complete the work is slated for April.

James Webb Space Telescope

Engineers at our Goddard Space Flight Center Center complete vibration and acoustic tesing on the James Webb Space Telescope, which was subjected to earsplitting noice and shaken 50-100 times per second to simulate the rigors of launch.

MAVEN

Data from our MAVEN, our Mars Atmosphere and Volatile EvolutioN, and published in the journal Science, concludes that solar wind and radiation are responsible for stripping Mars of its atmosphere and turning it into the frigid desert world it is today.

Most of the gas ever in the Red Planet’s atmosphere has been lost to space. The MAVEN team focused on the gas argon, estimating that 65% of it has been stripped from the planet. In 2015, the science team determined that atmospheric gas continues to be lost to space.

STEM Education

We participated in a Women’s History Month celebration and the Smithsonian Air and Space Museum. The program feature NASA astronauts and engineers. The were also projects to get girls interested in sciene, technology, engineering and math, or STEM, education. There was also a screening of the film ‘Hidden Figures,’ which relates the story of African-American female mathematicians who were instrumental in the agency’s efforts to launch humans to space.

NASA App on Fire TV

We’ve released our latest free NASA app on a whole new platform--Amazon Fire TV! The app is already available for Apple TV, iOS, and Android.Viewers can stream NASA TV, access 16,000+, download video and more!

Download the app: www.nasa.gov/nasaapp

What the full episode of This Week @ NASA:

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What are Perseid Meteors, and why should you be excited for them this year? Let us tell you!

The Perseid meteor shower is caused by debris from Comet Swift-Tuttle as it swings through the inner solar system and ejects a trail of dust and gravel along its orbit. When the Earth passes through the debris, specs of comet-stuff hit the atmosphere at 140,000 mph and disintegrate in flashes of light. Meteors from this comet are called Perseids because they seem to fly out of the constellation Perseus.

Last year, this meteor shower peaked during a bright “supermoon”, so visibility was reduced. Luckily, forecasters say the show could be especially awesome this year because the Moon is nearly new when the shower peaks on Aug. 12-13.

The best place to view the event is away from city lights around midnight. Under a clear, dark sky forecasters predict meteor rates as high as 100 per hour on peak night. So, get outside, look up and enjoy the show!

If your area has poor visibility on the peak night, we’ve got you covered! We’ll be hosting a live broadcast about the meteor shower from 10 p.m. EDT Wednesday, Aug. 12, to 2 a.m. Thursday, Aug. 13. In addition to footage from our live skycam, the program will highlight the science behind the Perseids, as well as our research related to meteors and comets. Tune in on NASA TV or our UStream Channel.

Vision & Microgravity...Can We See the Connection?

What do nutrition and genetics have in common? They could all be linked to vision problems experienced by some astronauts. We see people going up to space with perfect vision, but need glasses when the return home to Earth.

Why Does This Study Matter?

We want to be able to send astronauts to Mars, but losing vision capability along the way is a BIG problem. Discovering the cause and possible treatments or preventions will help us safely send astronauts deeper into space than ever before. 

It’s Like Solving a Mystery

We already have an idea of why vision changes occur, but the real mystery remains...why do some astronauts have these issues, and other’s don’t?

Now, let’s break it down:

Nutrition is more than just what you eat. It includes how those things work inside your body. The biochemistry behind how your muscles make energy, how your brain utilizes glucose and how vitamins help with biochemical functions...it’s all part of nutrition.

Genetics also play a part in the vision changes we’re seeing in space. Data shows that there are differences in blood chemistry between astronauts that had vision issues and those that did not. We found that individuals with vision issues had different blood chemistries even before their flight to space. That means that some astronauts could be predisposed to vision issues in space.

Just in January 2016, scientists discovered this possible link between genetics, nutrition and vision changes in astronauts. It makes it clear that the vision problem is WAY more complex than we initially thought. 

While we still don’t know exactly what is causing the vision issues, we are able to narrow down who to study, and refine our research. This will help find the cause, and hopefully lead to treatment and prevention of these problems.

Fluid Shifts

The weightless environment of space also causes fluid shifts to occur in the body. This normal shift of fluids to the upper body in space causes increased inter-cranial pressure which could be reducing visual capacity in astronauts. We are currently testing how this can be counteracted by returning fluids to the lower body using a “lower body negative pressure” suit, also known as Chibis.

Benefits on Earth

Research in this area has also suggested that there may be similarities between astronaut data and individuals with a clinical syndrome affecting 10-20% of women, known as polycystic ovary syndrome. Studying this group may provide a way to better understand vision and cardiovascular system effects, which could also advance treatment and prevention for both astronauts and humans on Earth with this disease.

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Do you have any protections against asteroids?

Farewell to the Van Allen Probes

After seven years of studying the radiation around Earth, the Van Allen Probes spacecraft have retired.

Originally slated for a two-year mission, these two spacecraft studied Earth's radiation belts — giant, donut-shaped clouds of particles surrounding Earth — for nearly seven years. The mission team used the last of their propellant this year to place the spacecraft into a lower orbit that will eventually decay, allowing the Van Allen Probes to re-enter and burn up in Earth's atmosphere.

Earth's radiation belts exist because energized charged particles from the Sun and other sources in space become trapped in our planet's huge magnetic field, creating vast regions around Earth that teem with radiation. This is one of the harshest environments in space — and the Van Allen Probes survived more than three times longer than planned orbiting through this intense region.

The shape, size and intensity of the radiation belts change, meaning that satellites — like those used for telecommunications and GPS — can be bombarded with a sudden influx of radiation. The Van Allen Probes shed new light on what invisible forces drive these changes — like waves of charged particles and electromagnetic fields driven by the Sun, called space weather. 

Here are a few scientific highlights from the Van Allen Probes — from the early days of the mission to earlier this year:

The Van Allen belts were first discovered in 1958, and for decades, scientists thought there were only two concentric belts. But, days after the Van Allen Probes launched, scientists discovered that during times of intense solar activity, a third belt can form.

The belts are composed of charged particles and electromagnetic fields and can be energized by different types of plasma waves. One type, called electrostatic double layers, appear as short blips of enhanced electric field. During one observing period, Probe B saw 7,000 such blips repeatedly pass over the spacecraft in a single minute!

During big space weather storms, which are ultimately caused by activity on the Sun, ions — electrically charged atoms or molecules — can be pushed deep into Earth’s magnetosphere. These particles carry electromagnetic currents that circle around the planet and can dramatically distort Earth’s magnetic field.

Across space, fluctuating electric and magnetic fields can create what are known as plasma waves. These waves intensify during space weather storms and can accelerate particles to incredible speeds. The Van Allen Probes found that one type of plasma wave known as hiss can contribute greatly to the loss of electrons from the belts.

The Van Allen belts are composed of electrons and ions with a range of energies. In 2015, research from the Van Allen Probes found that, unlike the outer belt, there were no electrons with energies greater than a million electron volts in the inner belt.

Plasma waves known as whistler chorus waves are also common in our near-Earth environment. These waves can travel parallel or at an angle to the local magnetic field. The Van Allen Probes demonstrated the two types of waves cannot be present simultaneously, resulting in greater radiation belt particle scattering in certain areas.

Very low frequency chorus waves, another variety of plasma waves, can pump up the energy of electrons to millions of electronvolts. During storm conditions, the Van Allen Probes found these waves can hugely increase the energy of particles in the belts in just a few hours.  

Scientists often use computer simulation models to understand the physics behind certain phenomena. A model simulating particles in the Van Allen belts helped scientists understand how particles can be lost, replenished and trapped by Earth’s magnetic field.

The Van Allen Probes observed several cases of extremely energetic ions speeding toward Earth. Research found that these ions’ acceleration was connected to their electric charge and not to their mass.

The Sun emits faster and slower gusts of charged particles called the solar wind. Since the Sun rotates, these gusts — the fast wind — reach Earth periodically. Changes in these gusts cause the extent of the region of cold ionized gas around Earth — the plasmasphere — to shrink. Data from the Van Allen Probes showed that such changes in the plasmasphere fluctuated at the same rate as the solar rotation — every 27 days.

Though the mission has ended, scientists will use data from the Van Allen Probes for years to come. See the latest Van Allen Probes science at nasa.gov/vanallen.

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6 Ways Earth Observations Tackle Real-World Problems

This summer, 30 research projects were launched by recent college graduates and early career professionals as part of our DEVELOP program. The aim is to use our satellite observations of Earth to address an environmental or public policy issue. And they have just 10 weeks to do it! On Aug. 10, 2016, the “DEVELOPers” gathered at our Headquarters in Washington, DC to showcase their results. So, how can Earth observations solve real-world problems? Let’s take a look:

1. They help land managers identify the locations of invasive species.

Austin Haney, DEVELOP project co-lead at University of Georgia, has seen first-hand how an invasive species can affect the ecosystem of Lake Thurmond, a large reservoir that straddles the border between Georgia and South Carolina. Birds in the area “behave visibly different,” he said, after they consume a toxic cyanobacteria that lives on Hydrilla verticillata, an invasive aquatic plant. Ingesting the toxin causes a neurodegenerative disease and ultimately death. Scores of birds have been found dead near lake areas where large amounts of the toxin-supporting Hydrilla grow. To help lake managers better address the situation, Haney and project members developed a tool that uses data from the Landsat 8 satellite to map the distribution of Hydrilla across the lake. 

Image Credit: NASA/Bill Ingalls

2. They help identify wildlife habitat threatened by wildfires.

Maps that depict habitat and fire risk in eastern Idaho previously stopped short of Craters of the Moon National Monument and Preserve, where shrubs and grasses transition to a sea of ankle-twisting basalt. But the environment is not as inhospitable as it first appears. Throughout the monument there are more than 500 kipukas —pockets of older lava capable of supporting some vegetation. That means it is also prone to burning. Project lead Courtney Ohr explained how her team used data from the Landsat 8 and Sentinel-2 satellites to develop a model that can simulate the area’s susceptibility to wildfires. Decision makers can use this model to monitor the remote wildlife habitat from afar.

Image Credit: NASA/Bill Ingalls

3. In conjunction with Instagram, they help find seaweed blooms

Who knew that Instagram could be a tool for science? One DEVELOP team searched for photographs of massive seaweed (sargassum) blooms in the Caribbean, mapped the locations, and then checked what satellites could see. In the process, they tested two techniques for finding algae and floating vegetation in the ocean.

Image Credit: Caribbean Oceans Team

4. They help conserve water by reducing urban stormwater runoff.

Atlanta’s sewer system is among the nation’s most expensive. Yet, the city still struggles with stormwater. It’s an uphill climb as new construction paves over more of the city, hindering its ability to absorb rain. The University of Georgia DEVELOP team partnered with The Nature Conservancy to address the problem.

Using satellite imagery, the team was able to pinpoint areas well-poised to capture more of the city’s runoff. They identified 17 communities ripe for expanding green infrastructure and reforestation. The team used the Land-Use Conflict Identification Strategy and Soil and Water Assessment Tool models and Landsat and Terra satellite data. Their analysis provides local groups with a working picture of the city’s water resources.

Image Credit: NASA/Bill Ingalls

5. They show the spread of the mite eating away Puerto Rico’s palm trees.

The red palm mite has devastated Puerto Rico’s trees in recent years. The insect chewed its way through coconut palms, bananas, and plantains on the island in the recent decade. Its spread has hurt crops across the Caribbean.

A DEVELOP team led by Sara Lubkin analyzed satellite imagery to track the mites’ rapid spread from 2002. The team mapped changes to vegetation, such as yellowing, and differences in canopy structure. They made use of imagery from Landsat, Hyperion, IKONOS, and aerial views. Their work can be used to mitigate current mite infestations and monitor and prevent future ones.

Image Credit: NASA/Bill Ingalls

6. They evaluate landslide-prone areas in the developing world

One team of DEVELOPers took on several projects to aid people in developing nations. This team from Alabama examined satellite imagery to find past landslides in the African nation of Malawi. Factors such as flooding after long periods of drought have made the country increasingly prone to landslides. Blending maps of the landscape, rainfall data, and population centers, the young researchers assessed the areas most at risk—and most in need of education and support—from landslides.

Image Credit: East Africa Disasters II Team

Want to read more about DEVELOP projects, or get involved? Summaries, images, and maps of current and past projects can be viewed HERE. You can also learn how to apply for the DEVELOP program HERE.  

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