Ever since NASA's Interstellar Boundary Explorer, or IBEX, mission scientists released the first comprehensive sky map of our solar system's edge in particles, solar physicists have been busy revising their models to account for the discovery of a narrow "ribbon" of bright emission that was completely unexpected and not predicted by any model at the time.

Further study by a team of scientists funded through NASA's Heliophysics Guest Investigator program has produced a revised model that explains and closely reproduces the IBEX result by incorporating a single new effect into an existing model. The new effect, put forward by the IBEX team soon after sighting of the ribbon, is that the magnetic field surrounding our solar system -- called the local galactic magnetic field -- acts like a mirror for the particles that IBEX sees.

Sometimes you really can believe your eyes. That's what NASA's Solar Terrestrial Relations Observatory (STEREO) is telling researchers about a controversial phenomenon on the sun known as the "solar tsunami."

Years ago, when solar physicists first witnessed a towering wave of hot plasma racing across the sun's surface, they doubted their senses. The scale of the wave was staggering: It rose up higher than Earth itself and rippled out from a central point in a circular pattern millions of kilometers in circumference. Skeptical observers suggested it might be a shadow of some kind -- a trick of the satellite's eye -- but surely not a real wave.

When NASA's Cassini spacecraft began orbiting Saturn five years ago, a dozen highly-tuned science instruments set to work surveying, sniffing, analyzing and scrutinizing the Saturnian system.

But Cassini recently revealed new data that appeared to overturn the decades-old belief that our solar system resembled a comet in shape as it moves through the interstellar medium (the matter between stars in our corner of the Milky Way galaxy).

Solar wind generated by the sun is probably driven by a process involving powerful magnetic fields, according to a new study led by UCL researchers based on the latest observations from the Hinode satellite.

Scientists have long speculated on the source of solar winds. The Extreme Ultraviolet Imaging Spectrometer (EIS), on board the Japanese-UK-US Hinode satellite, is now generating unprecedented observations enabling scientists to provide a new perspective on the 50-year old question of how solar wind is driven. The collaborative study, published in this month's issue of Astrophysical Journal, suggests that a process called slipping reconnection may drive these winds.

On Dec. 31, 2007, the sun awoke from the relatively quiescent period between Solar Cycles 23 and 24 to produce a solar flare that spewed high-energy neutrons into interplanetary space.

The Neutron Spectrometer flying aboard NASA's MESSENGER spacecraft recorded the event, giving scientists a first-ever, up-close look at neutron production from a solar flare. In fact, it was the first time scientists detected solar neutrons at less than 1 AU from the sun.

Images from the Ion and Neutral Camera on NASA's Cassini spacecraft suggest that the heliosphere, the region of the sun's influence, may not have the comet-like shape predicted by existing models.

In a paper published Oct. 15 in Science Express, researchers from the Johns Hopkins Applied Physics Laboratory present a new view of the heliosphere, and the forces that shape it.

The first all-sky maps developed by NASA's Interstellar Boundary Explorer (IBEX) spacecraft, the first mission to examine the global interactions occurring at the edge of the solar system, reveal surprising and intense interactions between our home in the galaxy and interstellar space.

"The IBEX results are truly remarkable, with emissions not resembling any of the current theories or models of this never-before-seen region," says Dr. David J. McComas, IBEX principal investigator and assistant vice president of the Space Science and Engineering Division at Southwest Research Institute. "We expected to see small, gradual spatial variations at the interstellar boundary, some ten billion miles away. However, IBEX is showing us a very narrow ribbon that is two to three times brighter than anything else in the sky."

Planning a trip to Mars? Take plenty of shielding. According to sensors on NASA's ACE (Advanced Composition Explorer) spacecraft, galactic cosmic rays have just hit a Space Age high.

"In 2009, cosmic ray intensities have increased 19% beyond anything we've seen in the past 50 years," says Richard Mewaldt of Caltech. "The increase is significant, and it could mean we need to re-think how much radiation shielding astronauts take with them on deep-space missions."

Every 11 years, the sun undergoes a furious upheaval. Dark sunspots burst forth from beneath the sun's surface. Explosions as powerful as a billion atomic bombs spark intense flares of high-energy radiation. Clouds of gas big enough to swallow planets break away and billow into space. It's a flamboyant display of stellar power.

So why can't we see any of it?

When NASA's Solar Dynamics Observatory (SDO) leaves Earth in November 2009 onboard an Atlas V rocket, the thunderous launch will trigger an avalanche. Mission planners are bracing themselves -- not for rocks or snow, but an avalanche of data.

"SDO will beam back 150 million bits of data per second, 24 hours a day, 7 days a week," says Dean Pesnell of the Goddard Space Flight Center in Greenbelt, Md. That's almost 50 times more science data than any other mission in NASA history. "It's like downloading 500,000 iTunes a day."

The Hinode satellite observing our sun captured images of the moon traversing the face of the sun during a solar eclipse this week.

On Wednesday, July 22, 2009, a total eclipse of the Sun was visible from within a narrow corridor that traverses half of Earth. The path of the Moon's umbral shadow began in India and crossed through Nepal, Bangladesh, Bhutan, Myanmar and China.

NASA is designing a mission to investigate one of the most fundamental and explosive physical processes in the universe - magnetic reconnection. Known as the Magnetospheric MultiScale (MMS) mission, it was approved for implementation on June 18, 2009 following a successful Preliminary Design Review in May 2009.

MMS consists of four identical satellites that will fly in a tetrahedron formation through Earth's magnetosphere to discover how magnetic reconnection works.

NASA's upcoming mission to study the sun in unprecedented detail and its effects on Earth, the Solar Dynamics Observatory (SDO), arrived at NASA's Kennedy Space Center, Fla. on July 9.

The spacecraft left NASA's Goddard Space Flight Center in Greenbelt, Md., on July 7, where it was built and tested.

In 2008, Ulysses was expected to cease functioning due to weakening power. But solid engineering know-how and on-the-fly innovation have eked out an additional year of important science returns, which came to an end yesterday.

Ulysses, the joint ESA/NASA solar orbiter mission, finally ended yesterday when ground controllers sent commands to shut down the satellite's communications. The event marks the conclusion of one of the longest and most successful space missions ever conducted.

Upon receipt of the last command from Earth, the transmitter on Ulysses will switch off on 30 June, bringing one of the most successful and longest missions in spaceflight history to an end.

After 18.6 years in space and defying several earlier expectations of its demise, the joint ESA/NASA solar orbiter Ulysses will achieve 'end of mission' on 30 June 2009. The final communication pass with a ground station will start at 15:35 UTC and run until 20:20 UTC or until the final command is issued to switch the satellite's radio communications into 'monitor only' mode. No further contact with Ulysses is planned.