orbital sciences

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A ‘Ring of Fire’ solar eclipse is a rare phenomenon that occurs when the moon’s orbit is at its apogee: the part of its orbit farthest away from the Earth. Because the moon is so far away, it seems smaller than normal to the human eye. The result is that the moon doesn't entirely block out our view of the sun, but leaves an “annulus,” or ring of sunlight glowing around it. Hence the term  “annular” eclipse rather than a “total” eclipse.

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Full moon rising over Los Angeles earlier this month

Incoming! We’ve Got Science from Jupiter!

Our Juno spacecraft has just released some exciting new science from its first close flyby of Jupiter! 

In case you don’t know, the Juno spacecraft entered orbit around the gas giant on July 4, 2016…about a year ago. Since then, it has been collecting data and images from this unique vantage point.

Juno is in a polar orbit around Jupiter, which means that the majority of each orbit is spent well away from the gas giant. But once every 53 days its trajectory approaches Jupiter from above its north pole, where it begins a close two-hour transit flying north to south with its eight science instruments collecting data and its JunoCam camera snapping pictures.

Space Fact: The download of six megabytes of data collected during the two-hour transit can take one-and-a-half days!

Juno and her cloud-piercing science instruments are helping us get a better understanding of the processes happening on Jupiter. These new results portray the planet as a complex, gigantic, turbulent world that we still need to study and unravel its mysteries.

So what did this first science flyby tell us? Let’s break it down…

1. Tumultuous Cyclones

Juno’s imager, JunoCam, has showed us that both of Jupiter’s poles are covered in tumultuous cyclones and anticyclone storms, densely clustered and rubbing together. Some of these storms as large as Earth!

These storms are still puzzling. We’re still not exactly sure how they formed or how they interact with each other. Future close flybys will help us better understand these mysterious cyclones. 

Seen above, waves of clouds (at 37.8 degrees latitude) dominate this three-dimensional Jovian cloudscape. JunoCam obtained this enhanced-color picture on May 19, 2017, at 5:50 UTC from an altitude of 5,500 miles (8,900 kilometers). Details as small as 4 miles (6 kilometers) across can be identified in this image.

An even closer view of the same image shows small bright high clouds that are about 16 miles (25 kilometers) across and in some areas appear to form “squall lines” (a narrow band of high winds and storms associated with a cold front). On Jupiter, clouds this high are almost certainly comprised of water and/or ammonia ice.

2. Jupiter’s Atmosphere

Juno’s Microwave Radiometer is an instrument that samples the thermal microwave radiation from Jupiter’s atmosphere from the tops of the ammonia clouds to deep within its atmosphere.

Data from this instrument suggest that the ammonia is quite variable and continues to increase as far down as we can see with MWR, which is a few hundred kilometers. In the cut-out image below, orange signifies high ammonia abundance and blue signifies low ammonia abundance. Jupiter appears to have a band around its equator high in ammonia abundance, with a column shown in orange.

Why does this ammonia matter? Well, ammonia is a good tracer of other relatively rare gases and fluids in the atmosphere…like water. Understanding the relative abundances of these materials helps us have a better idea of how and when Jupiter formed in the early solar system.

This instrument has also given us more information about Jupiter’s iconic belts and zones. Data suggest that the belt near Jupiter’s equator penetrates all the way down, while the belts and zones at other latitudes seem to evolve to other structures.

3. Stronger-Than-Expected Magnetic Field

Prior to Juno, it was known that Jupiter had the most intense magnetic field in the solar system…but measurements from Juno’s magnetometer investigation (MAG) indicate that the gas giant’s magnetic field is even stronger than models expected, and more irregular in shape.

At 7.766 Gauss, it is about 10 times stronger than the strongest magnetic field found on Earth! What is Gauss? Magnetic field strengths are measured in units called Gauss or Teslas. A magnetic field with a strength of 10,000 Gauss also has a strength of 1 Tesla.  

Juno is giving us a unique view of the magnetic field close to Jupiter that we’ve never had before. For example, data from the spacecraft (displayed in the graphic above) suggests that the planet’s magnetic field is “lumpy”, meaning its stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action (where the motion of electrically conducting fluid creates a self-sustaining magnetic field) closer to the surface, above the layer of metallic hydrogen. Juno’s orbital track is illustrated with the black curve. 

4. Sounds of Jupiter

Juno also observed plasma wave signals from Jupiter’s ionosphere. This movie shows results from Juno’s radio wave detector that were recorded while it passed close to Jupiter. Waves in the plasma (the charged gas) in the upper atmosphere of Jupiter have different frequencies that depend on the types of ions present, and their densities. 

Mapping out these ions in the jovian system helps us understand how the upper atmosphere works including the aurora. Beyond the visual representation of the data, the data have been made into sounds where the frequencies
and playback speed have been shifted to be audible to human ears.

5. Jovian “Southern Lights”

The complexity and richness of Jupiter’s “southern lights” (also known as auroras) are on display in this animation of false-color maps from our Juno spacecraft. Auroras result when energetic electrons from the magnetosphere crash into the molecular hydrogen in the Jovian upper atmosphere. The data for this animation were obtained by Juno’s Ultraviolet Spectrograph. 

During Juno’s next flyby on July 11, the spacecraft will fly directly over one of the most iconic features in the entire solar system – one that every school kid knows – Jupiter’s Great Red Spot! If anybody is going to get to the bottom of what is going on below those mammoth swirling crimson cloud tops, it’s Juno.

Stay updated on all things Juno and Jupiter by following along on social media:
Twitter | Facebook | YouTube | Tumblr

Learn more about the Juno spacecraft and its mission at Jupiter HERE.

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Here’s the orbital period of our solar system’s 8 major planets (how long it takes each to travel around the sun). Their size is to scale and their speed is accurate relative to Earth’s. The repetition of each GIF is proportional to their orbital period. Mercury takes less than 3 months to zoom around Sol, Neptune takes nearly 165 years.  

Let Us See Jupiter Through Your Eyes

Our Juno spacecraft will fly over Jupiter’s Great Red Spot on July 10 at 10:06 p.m. EDT. This will be humanity’s first up-close and personal view of the gas giant’s iconic 10,000-mile-wide storm, which has been monitored since 1830 and possibly existing for more than 350 years.

The data collection of the Great Red Spot is part of Juno’s sixth science flyby over Jupiter’s mysterious cloud tops. Perijove (the point at which an orbit comes closest to Jupiter’s center) will be July 10 at 9:55 p.m. EDT. 

At the time of perijove, Juno will be about 2,200 miles above the planet’s cloud tops. Eleven minutes and 33 seconds later…Juno will have covered another 24,713 miles and will be directly above the coiling crimson cloud tops of the Great Red Spot. The spacecraft will pass about 5,600 miles above its clouds. 

When will we see images from this flyby?

During the flyby, all eight of the spacecraft’s instruments will be turned on, as well as its imager, JunoCam. Because the spacecraft will be collecting data with its Microwave Radiometer (MWR), which measures radio waves from Jupiter’s deep atmosphere, we cannot downlink information during the pass. The MWR can tell us how much water there is and how material is moving far below the cloud tops.

During the pass, all data will be stored on-board…with a downlink planned afterwards. Once the downlink begins, engineering data from the spacecraft’s instruments will come to Earth first, followed by images from JunoCam.

The unprocessed, raw images will be located HERE, on approximately July 14. Follow @NASAJuno on Twitter for updates.

Did you know you can download and process these raw images?

We invite the public to act as a virtual imaging team…participating in key steps of the process, from identifying features of interest to sharing the finished images online. After JunoCam data arrives on Earth, members of the public can process the images to create color pictures. The public also helps determine which points on the planet will be photographed. Learn more about voting on JunoCam’s next target HERE.

JunoCam has four filters: red, green, blue and near-infrared. We get red, green and blue strips on one spacecraft rotation (the spacecraft rotation rate is 2 revolutions per minute) and the near-infrared strips on the second rotation. To get the final image product, the strips must be stitched together and the colors lined up.

Anything from cropping to color enhancing to collaging is fair game. Be creative!

Submit your images to Juno_outreach@jpl.nasa.gov to be featured on the Mission Juno website!

Check out some of these citizen-scientist processed images from previous Juno orbits: 

Credit: Sean Doran (More)

Credit: Amelia Carolina (More)

Credit: Michael Ranger (More)

Credit: Jason Major (More)

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Geometry at work: Orbital Resonance, Sound and Water

Richard Proctor, Old and New Astronomy, 1892

What men recognized then in the movements of the heavenly bodies is true now and true for all time. And even in dealing with the limited knowledge and the imperfect methods of ancient astronomers, we need not hesitate to consider these movements as they are now recognized and understood.

Ernst Chladni, Die Akustic, 1802

Nodal lines of vibrating circular or polygonal  plates, according to Chladni and Savart.The breakthrough work acquired a status of foundational work of a new scientific field and earned him a title of “father of acoustics”. It was the first systematic description of the vibrations of elastic bodies.

Snowflake Man

Wilson Alwyn “Snowflake” Bentley (February 7, 1865 – December 23, 1931), is one of the first known photographers of snowflakes. He perfected a process of catching flakes on black velvet in such a way that their images could be captured before they either melted or sublimated.

Jupiter is stranger than we knew. NASA’s Juno spacecraft completed its sixth swoop past Jupiter as it moves around its highly elliptical orbit. Pictured, Jupiter is seen from below where, surprisingly, the horizontal bands that cover most of the planet disappear into swirls and complex patterns. A line of white oval clouds is visible nearer to the equator. Recent results from Juno show that Jupiter’s weather phenomena can extend deep below its cloud tops, and that Jupiter’s magnetic field varies greatly with location. Juno is scheduled to orbit Jupiter 37 times with each orbit taking about six weeks. 

Image Credit: NASA, Juno, SwRI, MSSS, Gerald Eichstädt & Seán Doran

The Past, Present and Future of Exploration on Mars

Today, we’re celebrating the Red Planet! Since our first close-up picture of Mars in 1965, spacecraft voyages to the Red Planet have revealed a world strangely familiar, yet different enough to challenge our perceptions of what makes a planet work.

You’d think Mars would be easier to understand. Like Earth, Mars has polar ice caps and clouds in its atmosphere, seasonal weather patterns, volcanoes, canyons and other recognizable features. However, conditions on Mars vary wildly from what we know on our own planet.

Join us as we highlight some of the exploration on Mars from the past, present and future:

PAST

Viking Landers

Our Viking Project 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. Two identical spacecraft, each consisting of a lander and an orbiter, were built. Each orbiter-lander pair flew together and entered Mars orbit; the landers then separated and descended to the planet’s surface.

Besides taking photographs and collecting other science data, the two landers conducted three biology experiments designed to look for possible signs of life.

Pathfinder Rover

In 1997, Pathfinder was the first-ever robotic rover to land on the surface of Mars. It was designed as a technology demonstration of a new way to deliver an instrumented lander to the surface of a planet. Mars Pathfinder used an innovative method of directly entering the Martian atmosphere, assisted by a parachute to slow its descent and a giant system of airbags to cushion the impact.

Pathfinder not only accomplished its goal but also returned an unprecedented amount of data and outlived its primary design life.

PRESENT

Spirit and Opportunity

In January 2004, two robotic geologists named Spirit and Opportunity landed on opposite sides of the Red Planet. With far greater mobility than the 1997 Mars Pathfinder rover, these robotic explorers have trekked for miles across the Martian surface, conducting field geology and making atmospheric observations. Carrying identical, sophisticated sets of science instruments, both rovers have found evidence of ancient Martian environments where intermittently wet and habitable conditions existed.

Both missions exceeded their planned 90-day mission lifetimes by many years. Spirit lasted 20 times longer than its original design until its final communication to Earth on March 22, 2010. Opportunity continues to operate more than a decade after launch.

Mars Reconnaissance Orbiter

Our Mars Reconnaissance Orbiter left Earth in 2005 on a search for evidence that water persisted on the surface of Mars for a long period of time. While other Mars missions have shown that water flowed across the surface in Mars’ history, it remained a mystery whether water was ever around long enough to provide a habitat for life.

In addition to using the rover to study Mars, we’re using data and imagery from this mission to survey possible future human landing sites on the Red Planet.

Curiosity

The Curiosity rover is the largest and most capable rover ever sent to Mars. It launched November 26, 2011 and landed on Mars on Aug. 5, 2012. Curiosity set out to answer the question: Did Mars ever have the right environmental conditions to support small life forms called microbes? 

Early in its mission, Curiosity’s scientific tools found chemical and mineral evidence of past habitable environments on Mars. It continues to explore the rock record from a time when Mars could have been home to microbial life.

FUTURE

Space Launch System Rocket

We’re currently building the world’s most powerful rocket, the Space Launch System (SLS). When completed, this rocket will enable astronauts to begin their journey to explore destinations far into the solar system, including Mars.

Orion Spacecraft

The Orion spacecraft will sit atop the Space Launch System rocket as it launches humans deeper into space than ever before. Orion will serve as the exploration vehicle that will carry the crew to space, provide emergency abort capability, sustain the crew during the space travel and provide safe re-entry from deep space return velocities.

Mars 2020

The Mars 2020 rover mission takes the next step in exploration of the Red Planet by not only seeking signs of habitable conditions in the ancient past, but also searching for signs of past microbial life itself.

The Mars 2020 rover introduces a drill that can collect core samples of the most promising rocks and soils and set them aside in a “cache” on the surface of Mars. The mission will also test a method for producing oxygen from the Martian atmosphere, identify other resources (such as subsurface water), improve landing techniques and characterize weather, dust and other potential environmental conditions that could affect future astronauts living and working on the Red Planet.

For decades, we’ve sent orbiters, landers and rovers, dramatically increasing our knowledge about the Red Planet and paving the way for future human explorers. Mars is the next tangible frontier for human exploration, and it’s an achievable goal. There are challenges to pioneering Mars, but we know they are solvable. 

To discover more about Mars exploration, visit: https://www.nasa.gov/topics/journeytomars/index.html

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The total solar eclipse is coming! Here’s your chance to ask an eclipse scientist your questions!

Have questions about the upcoming total solar eclipse on August 21? Join our Tumblr Answer Time session on Thursday, August 17 from 3:00 – 4:00 p.m. EDT/12:00 - 1:00 p.m. PDT. here on NASA’s Tumblr, where space physics researcher Alexa Halford will answer them. Make sure to ask your questions now by visiting: https://nasa.tumblr.com/ask!

See all the #AnswerTime questions here: https://nasa.tumblr.com/tagged/answertime

Alexa Halford is a space physics researcher at our Goddard Space Flight Center and Dartmouth College. She started researching waves in Earth’s magnetosphere as an undergraduate at Augsburg College with Mark Engebretson using ground based magnetometers in the Arctic and Antarctic. She moved away from waves to focus on geomagnetic storms and substorms during her masters at the University of Colorado Boulder with Dan Baker but returned once more to waves with her PhD at University of Newcastle NSW Australia. Her PhD thesis was on Electromagnetic Ion Cyclotron (EMIC) waves during the CRRES mission and their relationship to the plasmasphere and radiation belts.

She is member of the scientific team for a NASA-funded scientific balloon experiment project called BARREL (Balloon Array for RBSP Relativistic Electron Losses) where she looks at the population of particles lost due to these interactions. She is now currently a contractor at NASA Goddard continuing work the BARREL and NASA Van Allen Probes satellite missions.

To get more information about the eclipse, visit: https://eclipse2017.nasa.gov/

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