Radar Observations Of Asteroid 2014 HQ124

Celebrating 10 Years of Revolutionary Solar Views

Twin spacecraft give humanity unprecedented views of the entire sun at one time, traveling to the far side of our home star over the course of a 10-year mission.

These two spacecraft are called STEREO, short for Solar and Terrestrial Relations Observatory. Launched on Oct. 25, 2006, and originally slated for a two-year mission, both spacecraft sent back data for nearly eight years, and STEREO-A still sends information and images from its point of view on the far side of the sun.

STEREO watches the sun from two completely new perspectives. It also provides information invaluable for understanding the sun and its impact on Earth, other worlds, and space itself – collectively known as space weather. On Earth, space weather can trigger things like the aurora and, in extreme cases, put a strain on power systems or damage high-flying satellites.

Because the rest of our sun-watching satellites orbit near our home planet, STEREO’s twin perspectives far from Earth give us a unique opportunity to look at solar events from all sides and understand them in three dimensions.

We use data from STEREO and other missions to understand the space environment throughout the solar system. This helps operators for missions in deep space prepare for the sudden bursts of particles and magnetic field that could pose a danger to their spacecraft. 

STEREO has also helped us understand other objects in our solar system – like comets. Watching how a comet’s tail moves gives us clues about the constant stream of particles that flows out from the sun, called the solar wind.

STEREO is an essential piece of our heliophysics fleet, which includes 17 other missions. Together, these spacecraft shed new light on the sun and its interaction with space, Earth, and other worlds throughout the solar system. 

To celebrate, we’re hosting a Facebook Live event on Wednesday, Oct. 26. Join us at noon ET on the NASA Sun Science Facebook page to learn more about STEREO and ask questions. 

Learn more about how NASA studies the sun at: www.nasa.gov/stereo

Follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

The Van Allen Belt & the South Atlantic Anomaly

NASA’s first satellite, launched in 1958, discovered two giant swaths of radiation encircling Earth. Five decades later, scientists are still trying to unlock the mysteries of these phenomena known as the Van Allen belt. The belt is named after its discoverer, American astrophysicist James Van Allen.

The near-Earth space environment is a complex interaction between the planet’s magnetic field, cool plasma moving up from Earth’s ionosphere, and hotter plasma coming in from the solar wind. This dynamic region is populated by charged particles (electrons and ions) which occupy regions known as the plasmasphere and the Van Allen radiation belt. As solar wind and cosmic rays carry fast-moving, highly energized particles past Earth, some of these particles become trapped by the planet’s magnetic field. These particles carry a lot of energy, and it is important to mention their energies when describing the belt, because there are actually two distinct belts; one with energetic electrons forming the outer belt, and a combination of protons and electrons creating the inner belt. The resulting belts, can swell or shrink in size in response to incoming particles from Earth’s upper atmosphere and changes in the solar wind. Recent studies suggest that there is boundary at the inner edge of the outer belt at roughly 7,200 miles in altitude that appears to block the ultrafast electrons from breaching the invisible shield that protects Earth. 

Earth’s magnetic field doesn’t exactly line up with the planet’s rotation axis, the belts are actually tilted a bit. Because of this asymmetry, one of the shields that trap potentially harmful particles from space dips down to 200 km (124 mi) altitude.

This dip in the earth’s magnetic field allows charged particles and cosmic rays to reach lower into the atmosphere. Satellites and other low orbiting spacecraft passing through this region of space actually enter the Van Allen radiation belt and are bombarded by protons. Exposure to such radiation can wreak havoc on satellite electronics, and pose serious health risks to astronauts. This peculiar region is called the South Atlantic Anomaly.

Credit: NASA/ESA/M. Kornmesser

(no word to describe this feeling)

eat mor chikin

The Cat’s Eye Nebula (NGC 6543) is one of the best known planetary nebulae in the sky. Its more familiar outlines are seen in the brighter central region of the nebula in this impressive wide-angle view. But the composite image combines many short and long exposures to also reveal an extremely faint outer halo. At an estimated distance of 3,000 light-years, the faint outer halo is over 5 light-years across. Planetary nebulae have long been appreciated as a final phase in the life of a sun-like star. More recently, some planetary nebulae are found to have halos like this one, likely formed of material shrugged off during earlier episodes in the star’s evolution. While the planetary nebula phase is thought to last for around 10,000 years, astronomers estimate the age of the outer filamentary portions of this halo to be 50,000 to 90,000 years. Visible on the left, some 50 million light-years beyond the watchful planetary nebula, lies spiral galaxy NGC 6552.

Object Names: Cat’s Eye Nebula, NGC 6543

Image Type: Astronomical

Credit: Josh Smith (Via Nasa)

Time And Space

Nearly every day Cassini sends back something amazing to sit and wonder at.

1) Saturn’s rings, 15 July 2014

2) Tethys / Saturn’s rings 14 July 2014

3) Disk of Saturn 14 July 2014

4) Prometheus / F Ring 13 July 2014

5) Pan in the Encke Gap 13 July 2014

All raw and unprocessed images from saturn.jpl.nasa.gov

Windswept by Charles Sowers

Though we cannot physically hold wind or see its swirling forms around us, we can definitely feel it.

In order to help visualize wind-currents, artist Charles Sowers created a kinetic installation consisting of 612 aluminum weather vanes called “Windswept” (2011). These were then meticulously placed on the side of the Randall Museum in San Francisco. Through this installation, we are able to see the patterns in the wind; where the currents go, how they turn, and sometimes how wind can abruptly change direction. This gives us a visual representation of the natural, invisible, force which moves around us, and sometimes with enough force, pushes and pulls us.

As the artist states: “Our ordinary experience of wind is as a solitary sample point of a very large invisible phenomenon. Windswept is a kind of large sensor array that samples the wind at its point of interaction with the Randall Museum building and reveals the complexity and structure of that interaction.”

This sort of installation creates a better understanding, and appreciation, of the wind. It is not just one large gust; a single wave can be made up of smaller currents, going in their own directions from the main flow. A dialogue begins to form between the building and the wind, the weather vanes acting as translators.

-Anna Paluch

That’s Electrooculography!

The eye is a basically a dipole ( a separation of electric charges )

It was observed by Reymond in 1848 that the cornea of the eye is electrically positive relative to the back of the eye.This potential was surprisingly not dependent on the amount of light falling on the eye.

                The cornea is the transparent front part of the eye

Dipoles and Eye Tracking

This means that as the eye moves from side to side, the dipole moves as well. To capture the movement of the dipole, one places two electrodes on both sides of the eye. ( like the one placed on this guy )

If the eye moves from the center position to the right, one of the electrodes becomes slightly positive and the other negative. This leads to a spike in the positive direction.

                                                  Source

And if the eye moves from the center position to the left, the polarity of the electrodes reverses. This leads to a spike in the negative direction.

That’s about it. That’s EOG for you all. I hope you guys enjoyed this post.

Have a great day!

Sources and Extras:

More about EOG

Gif source : The backyard brains

Drops of a liquid can often join a pool gradually through a process known as the coalescence cascade (top left). In this process, a drop sits atop a pool, separated by a thin air layer. Once that air drains out, contact is made and part of the drop coalesces. Then a smaller daughter droplet rebounds and the process repeats.

A recent study describes a related phenomenon (top right) in which the coalescence cascade is drastically sped up through the use of surfactants. The normal cascade depends strongly on the amount of time it takes for the air layer between the drop and pool to drain. By making the pool a liquid with a much greater surface tension value than the drop, the researchers sped up the air layer’s drainage. The mismatch in surface tension between the drop and pool creates an outward flow on the surface (below) due to the Marangoni effect. As the pool’s liquid moves outward, it drags air with it, thereby draining the separating layer more quickly. The result is still a coalescence cascade but one in which the later stages have no rebound and coalesce quickly. (Image and research credit: S. Shim and H. Stone, source)

WORKING ON CHRISTMAS: While the beautiful Earth looms in the background, astronaut Steven Smith stands on the mobile foot restraint at the end of the remote manipulator system as he makes repairs to the Hubble Space Telescope, Dec. 24-25, 1999. (NASA)

Solar System: Things to Know This Week

Learn the latest on Cassini’s Grand Finale, Pluto, Hubble Space Telescope and the Red Planet.

1. Cassini’s Grand Finale

After more than 12 years at Saturn, our Cassini mission has entered the final year of its epic voyage to the giant planet and its family of moons. But the journey isn’t over. The upcoming months will be like a whole new mission, with lots of new science and a truly thrilling ride in the unexplored space near the rings. Later this year, the spacecraft will fly repeatedly just outside the rings, capturing the closest views ever. Then, it will actually orbit inside the gap between the rings and the planet’s cloud tops.

Get details on Cassini’s final mission

The von Kármán Lecture Series: 2016

2. Chandra X-Rays Pluto

As the New Horizon’s mission headed to Pluto, our Chandra X-Ray Observatory made the first detection of the planet in X-rays. Chandra’s observations offer new insight into the space environment surrounding the largest and best-known object in the solar system’s outermost regions.

See Pluto’s X-Ray

3. … And Then Pluto Painted the Town Red

When the cameras on our approaching New Horizons spacecraft first spotted the large reddish polar region on Pluto’s largest moon, Charon, mission scientists knew two things: they’d never seen anything like it before, and they couldn’t wait to get the story behind it. After analyzing the images and other data that New Horizons has sent back from its July 2015 flight through the Pluto system, scientists think they’ve solved the mystery. Charon’s polar coloring comes from Pluto itself—as methane gas that escapes from Pluto’s atmosphere and becomes trapped by the moon’s gravity and freezes to the cold, icy surface at Charon’s pole.

Get the details

4. Pretty as a Postcard

The famed red-rock deserts of the American Southwest and recent images of Mars bear a striking similarity. New color images returned by our Curiosity Mars rover reveal the layered geologic past of the Red Planet in stunning detail. 

More images

5. Things Fall Apart

Our Hubble Space Telescope recently observed a comet breaking apart. In a series of images taken over a three-day span in January 2016, Hubble captured images of 25 building-size blocks made of a mixture of ice and dust drifting away from the comet. The resulting debris is now scattered along a 3,000-mile-long trail, larger than the width of the continental U.S.

Learn more

Discover the full list of 10 things to know about our solar system this week HERE.

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