Plasma physicists have made an unprecedented measurement in their study of the Earth's magnetic field. Thanks to ESA's Cluster satellites they detected an electric field thought to be a key element in the process of 'magnetic reconnection'.

Thanks to these measurements, obtained by the eight PEACE electron sensors onboard the four spacecraft, scientists now have their first insight into magnetic reconnection's detailed behaviour. Magnetic reconnection is a process that can occur almost anywhere that a magnetic field is found. In a reconnection event, the magnetic field lines are squeezed together somehow and spontaneously reconfigure themselves. This releases energy. When it occurs near the surface of the Sun, such an event powers giant solar flares that can release thousands of millions of tonnes of electrically charged particles into space.

Although very close to the minimum of its 11-year sunspot cycle, the Sun showed that it is still capable of producing a series of remarkably energetic outbursts - ESA-NASA Ulysses mission revealed.

In keeping with the first and second south polar passes (in 1994 and 2000), the latest high-latitude excursion of the joint ESA-NASA Ulysses mission has already produced some surprises. In mid-December 2006, although very close to the minimum of its 11-year sunspot cycle, the Sun showed that it is still capable of producing a series of remarkably energetic outbursts.

NASA's THEMIS mission successfully launched Saturday, Feb. 17, at 23:01 UTC from Pad 17-B at Cape Canaveral Air Force Station, Fla.

THEMIS stands for the Time History of Events and Macroscale Interactions during Substorms. It is NASA's first five-satellite mission launched aboard a single rocket. The spacecraft separated from the launch vehicle approximately 73 minutes after liftoff. By 01:07 UTC, mission operators at the University of California, Berkeley, commanded and received signals from all five spacecraft, confirming nominal separation status.

Giant electrical circuits power the magical open-air light show of the auroras, forming arcs in high-latitude regions like Scandinavia. New results obtained thanks to ESA's Cluster satellites provide a new insight into the source of the difference between the two types of electrical circuits currently known to be associated to the auroral arcs.

The deep mechanisms that rule the creation of the beautiful auroras, or polar lights, have been the subject of studies that are keeping solar and plasma scientists busy since years. While early rockets and ground-observations have already provided a few important clues for the understanding of these phenomena, the real break-throughs in our knowledge have started with dedicated auroral satellites, such as S3-3, Dynamics Explorer, Viking, Freja and FAST, and have now come to full fruition with ESA's multi-point mission Cluster.

Today the joint ESA-NASA Ulysses mission has marked another high point in its mission. For the third time in a long and highly successful career, Ulysses has reached its maximum south solar latitude of 80 degrees as it flies over the Sun's southern polar cap.

Launched in 1990, the European-built spacecraft visits both polar regions once every 6.2 years as it circles the Sun in an orbit that is almost perpendicular to the ecliptic, the plane in which the Earth and the planets move.

NASA's twin STEREO (Solar TErrestrial RElations Observatory) spacecraft, managed by NASA Goddard Space Flight Center, Greenbelt, Md., completed a series of complex maneuvers January 21 to position the spacecraft in their mission orbits. The spacecraft will be in position to produce the first 3-D images of the sun by April.

"STEREO is now officially ready to start its science missions," says Michael Kaiser, STEREO Project Scientist at Goddard.

NASA's THEMIS, the Time History of Events and Macroscale Interactions during Substorms mission, is set to venture into space and help resolve the mystery of what triggers geomagnetic substorms. For the first time, scientists will get a comprehensive view of the substorm phenomena from Earth's upper atmosphere to far into space, pinpointing where and when each substorm begins.

Substorms are atmospheric events visible in the northern hemisphere as a sudden brightening of the Northern Lights. THEMIS also will provide clues about the role of substorms in severe space weather and identify where and when substorms begin.

Recently, sky watchers in the Northern Hemisphere have been enjoying the sight of Comet McNaught in the twilight sky. Now, solar physicists using the ESA-NASA SOHO spacecraft are getting ready for their view. For four days in January, the comet will pass through SOHO's line of sight and could be the brightest comet SOHO has ever seen.

As Comet McNaught heads towards its closest approach to the Sun on 12 January 2007, it will disappear from view for earthbound observers, becoming lost in the Sun's glare. That's where SOHO comes in. Poised in space between the Earth and Sun, SOHO ceaselessly watches the Sun and objects that pass nearby.

NASA's Time History of Events and Macroscale Interactions During Substorms (THEMIS) spacecraft arrived in Florida today, to begin final testing and launch preparations. THEMIS is scheduled to lift off on Feb. 15 aboard a Delta II rocket from Launch Complex 17-B on Cape Canaveral Air Force Station, Fla.

THEMIS consists of five identical probes, the largest number of scientific satellites ever launched into orbit aboard a single rocket. This unique constellation of satellites will resolve the tantalizing mystery of what causes the spectacular sudden brightening of the aurora borealis and aurora australis - the fiery skies over the Earth's northern and southern polar regions.

On 17 November, the joint ESA-NASA Ulysses mission reaches another important milestone on its epic out-of-ecliptic journey: the start of the third passage over the Sun's south pole.

Launched in 1990, the European-built spacecraft is engaged in the exploration of the heliosphere, the bubble in space blown out by the solar wind. Given the capricious nature of the Sun, this third visit will undoubtedly reveal new and unexpected features of our star's environment. The first polar passes in 1994 (south) and 1995 (north) took place near solar minimum, whereas the second set occurred at the height of solar activity in 2000 and 2001.

On 8 November 2006, the Science Programme Committee (SPC) of the European Space Agency (ESA) has approved a 9 months extension of ESA involvement in the Double Star Programme (DSP) operations from 1 January 2007 to 30 September 2007.

The Double Star mission is the first mission conducted in collaboration between ESA and the Chinese National Space Administration. The mission comprises two spacecraft to investigate magnetospheric global processes and their responses to interplanetary disturbances, in particular in conjunction with the Cluster mission.

On Wednesday 8 November 2006, Mercury will pass directly between the Sun and the Earth. The innermost planet will be seen not as a bright point in the sky but as a tiny black dot, silhouetted against the brilliant surface of the Sun. Although this spectacle is not visible from Europe, the ESA-NASA solar satellite SOHO will be watching.

Such a crossing is known as a transit. From Earth's vantage point, only Mercury and Venus transit the Sun, because these are the only planets inside Earth's orbit. In the case of Venus, the planet is large enough to be seen against the Sun without optical aid, providing that a pair of solar filters is worn to cut down the damaging glare of the Sun.

The Hinode (formerly Solar-B) satellite, a joint Japan/NASA/PPARC mission launched on 22nd September 2006, has today (October 31st) reported its first observations of the Sun with its suite of scientific instruments. The satellite was renamed 'Hinode' which is Japanese for Sunrise, which is most appropriate since Hinode will watch at close hand massively explosive solar flares erupting from the Sun's surface and rising into interstellar space.

Hinode has three instruments: the Solar Optical Telescope (SOT), the X-Ray Telescope (XRT), and the EUV Imaging Spectrometer (EIS) which has been led by University College London's Mullard Space Science Laboratory (MSSL).

NASA's twin Solar Terrestrial Relations Observatories mission, known as STEREO, successfully launched Thursday at 00:52 UTC from Cape Canaveral Air Force Station, Fla.

STEREO's nearly identical twin, golf cart-sized spacecraft will make observations to help researchers construct the first-ever three-dimensional views of the sun. The images will show the star's stormy environment and its effects on the inner solar system, vital data for understanding how the sun creates space weather.

European experts have played an integral role in developing and building the instruments on NASA's STEREO spacecraft. This exciting new solar mission will allow scientists to build on the work of the ESA/NASA SOlar and Heliospheric Observatory (SOHO) mission.

The STEREO mission consists of a pair of spacecraft that will separate after launch and move apart. This will allow them to look at the Sun simultaneously from different angles.