NASA STEREO A & B Spacecraft Communications to be Blocked by the Sun - Video

NASA Stereo Project team have stated that communication with the two STEREO spacecraft will soon cease when the sun blocks Earth's view of them. This position is known in astronomy as a superior conjunction.

This will happen for STEREO-Ahead from March 24 to July 7, 2015. STEREO-Behind will be in superior conjunction from January 22 to March 23, 2015.

During this period the NASA Stereo Project team claim that at least one spacecraft will always be collecting data, but that because of their position relative to the Sun, communications will be severely reduced.

The ability of Stereo A and Stereo B to gather scientific data on the Sun and transmit data back to Earth, will be greatly reduced during 2015 and on into 2016.

NASA SDO: Giant Convection cells found on the Sun

Giant cell flow trajectories on the Sun for June 8, 2010. 

The underlying cell pattern shows westerly winds in red and easterly winds in blue. 

Credit: David Hathaway /NASA

A trio of researchers with affiliations with NASA and several U.S. institutions has found the elusive giant convection cells suspected for nearly a half century to exist on and within the sun.

In their paper published in the journal Science, the team describes how they used data from a NASA Solar observatory (SDO) that captured solar information every 45 seconds over a several month period which allowed the researchers to track the slow movement of the giant cells.

The sun generates a lot of heat in its core, of course—heat that is conveyed to its outer portions and eventually into space.

That process occurs due to convection, and scientists have known about two types of convection sources (known as cells) for quite some time: granules and super granules—the former are small and travel very rapidly while the latter are planet sized and travel less swiftly.

A close-up of tight packs of coils around one active region (Nov. 18-19, 2013). 

The bundles of coils are actually charged particles swirling along magnetic field lines. 

Other field lines heading off to the left are more elongated and tapered. 

The images were taken in extreme ultraviolet light. 

Credit: Solar Dynamics Observatory.

Scientists have suspected for half a century that there is a third type of cell, a giant, also at play and that they have perhaps an even bigger impact on moving not just heat through the sun, but magnetism as well.

In this new effort, the researchers report that they've been able to definitively identify such cells, moving them from theory, to an observed phenomenon.

The reason that researchers have had so much difficulty in identifying giant cells, is because they move so slowly.

In finally finding them, the researchers have discovered that they move only at about ten meters per second—which when compared with the immense size of the sun, means they are not really going to stand out.

To get past that problem, the researchers looked at minute-by-minute data from NASA's Solar Dynamics Observatory.

Averaging the data allowed for observation of large groups of super granules being moved by something else—giant cells.

Besides proving theory correct, identifying giant cells on the sun might help to better predict solar events that have a direct impact on us—solar flares, coronal mass ejections, etc.—all can wreak havoc on man-made electronics.

Figuring out how to predict such events and to determine their size in advance could go a long way towards helping to build a system to automatically shut down sensitive equipment before such an event occurs.

More information: Giant Convection Cells Found on the Sun, Science 6 December 2013: Vol. 342 no. 6163 pp. 1217-1219 DOI: 10.1126/science.1244682

Observing Sunrise: Solar scientists review Hinode findings

Japan has a long tradition in solar physics and in 2006 launched one of the major space observatories – Hinode, which means 'sunrise' in Japanese.

For almost six years this satellite has been constantly monitoring our local star with a suite of three telescopes: the Solar Optical Telescope, X-ray Telescope and Extreme Ultraviolet Imaging Spectrometer (EIS).

Solar Optical Telecope

Together, they enable the study of how magnetic energy is generated and released in the atmosphere of our Sun.

This week in St. Andrews over 150 scientists from around the world gathered for the "Hinode 6" conference to celebrate what has been learnt using the Hinode satellite.

Although launched and led by Japan, the satellite has major contributions from the UK, the USA and Norway.

Extreme Ultraviolet Imaging Spectrometer (EIS)

Unexpectedly, St. Andrews has a connection to Hinode’s modern observing methods that dates back to the late 1600s.

The Scottish mathematician James Gregory upon walking along the beach in St. Andrews, Scotland, picked up a feather and wondered what would happen if a beam of light were shone through it.

Isaac Newton was conducting similar experiments with glass prisms in Cambridge.

Back in his lab, Gregory saw that the feather split the light into its component colours in a process now known as diffraction – a simple technique that is used today in many solar telescopes as it allows us to measure the properties of sunlight and in turn learn about the star that emitted it.

The Solar Science department at UCL led the development of the EIS telescope - a modern equivalent to the bird’s feather - which splits the ultraviolet light emitted from atmospheric gases into the component colours.

A major topic for discussion at the conference has been how magnetic fields that emanate up from the Sun’s surface into the atmosphere, create structures that glow in ultraviolet and X-rays and produce activity such as solar flares and coronal mass ejections (CME).

A large X-class flare captured by the X-ray telescope on Hinode. Image credit: JAXA/Hinode

High-speed gas flows associated to solar flares have been observed, helping scientists understand the processes that convert energy stored in the magnetic fields into energy of gas motions.

Computer models have been combined with observations to understand how currents surge along the magnetic structures, supported by the charged particles of the atmospheric gases, heating the atmospheric gases to very high temperatures.

Read the full article here at SEN: Solar scientists review Hinode findings

NASA's Degradation Free Spectrometers - Successful launch

On July 24, 2012, NASA successfully launched a pair of newly developed spectrometers aboard a sounding rocket from the White Sands Missile Range, New Mexico to an altitude of 323.8 km (201.2 mi).

This may not seem to have much to do with extending the life of a satellite floating between the Sun and Earth about 1.5 million kilometers (932,000 mi) away, but it does.

That’s because the tests' purpose was both to test new instruments for a potential future replacement of the SOHO solar observatory satellite and to recalibrate SOHO’s existing instruments.

See NASA ESA SOHO's Latest Images Here

It’s great when a space mission lasts longer than expected. Though the history of space exploration has been punctuated by failure and even tragedy, some missions shine out, such as the Viking and Opportunity Mars Landers, which operated years beyond their very short mission objectives and, of course, Voyager, a craft that is still working a generation after its launch.

However, success can bring its own problems. One of these is that a still-functioning craft may have to work with instruments never meant to last so long and are now showing their age.

A case in point is the Solar and Heliospheric Observatory (SOHO). This joint project between the European Space Agency (ESA) and NASA was launched on December 2, 1995 and is currently parked at the Lagrange point between the Earth and the Sun where gravitational forces balance, leaving it forever in the one spot.

Since its launch, it’s been studying the Sun and has discovered over 2,200 comets. Originally planned as a two-year mission, SOHO continues to send back data.

It’s done a great job and, more importantly, is the main source of near-real time data that helps look out for solar flares. Trouble is, the instruments weren’t designed to run for 18 years and they show it. Filters degrade, surfaces become contaminated, telescope mirrors dim... In other words, it’s going slowly blind.

There isn’t much that can be done to repair SOHO, but future missions will benefit from more durable instruments. That is the purpose of the sounding rocket test.

Among its payload were two Degradation Free Spectrometers (DFS). These are similar to the spectrometers used by SOHO, but where the satellite’s are gradually failing, these are designed to avoid that fate on a future mission.

Instead of conventional optics, they use a rare gas photoionization-based Optics-Free Spectrometer (OFS) {pdf} and a Dual Grating Spectrometer (DGS) {pdf}. These are made filter-free and optics-free by using rare-gas chambers, photoelectron focusing techniques, gratings and light baffles to exclude unwanted light without filters.

The mission was mainly to test the spectrometers, which are capable of, in the words of NASA’s press release, “high cadence measurements of the highly variable Extreme Ultraviolet (EUV) solar flux and have minimal degradation over multi-year time scales while observing the sun 24/7."

What that means is that the spectrometers can make precise observations of the Sun at the extreme end of the ultraviolet spectrum for years on end without the mechanism wearing out.

The other purpose was to help calibrate SOHO. In addition to the new spectrometers, the sounding rocket also carried a clone of SOHO’s Solar Extreme Ultraviolet Monitor (SEM) {pdf}.

This was calibrated at the National Institute of Standards and Technology both before and after flight to provide a calibration check for SOHO, so observations from the satellite can be corrected. If all goes well, it may give SOHO a little more life and its successor a lot more time.

New German scope will study the Sun

One of the major centres for solar studies is on the holiday island of Tenerife, high on the Moon-like landscape of the plateau surrounding Mount Teide called Las Canadas.

I remember this already being an important observatory with way back in the early Seventies when I was a young site-tester on the plateau checking sky conditions for another planned observatory that ended up being built on the neighbouring island of La Palma.

Now a new German solar telescope has been added to the mushrooming number of solar instruments at the site, called the Spanish Observatorio del Teide of the Instituto de Astrofísica de Canarias at Izaña. Called GREGOR, it is the largest solar telescope in Europe and the third biggest in the world.

This telescope, which will be inaugurated on May 21, is unusual because it will also be used at night to observe bright stars and compare their cycle of activity changes with the Sun.

GREGOR has a mirror 1.5 metres across (5ft) and will observe the Sun’s visible surface, called the photosphere, and the lower region of its atmosphere called the chromosphere, in the visible and infrared regions of the spectrum.

A range of instruments in neighbouring laboratory rooms will examine the light to study how these solar regions interact with the Sun’s magnetic field and movement of hot plasma.

Like many telescopes nowadays, a system of adaptive optics will compensate for atmospheric disturbances. Together with the large diameter this will allow observation of the Sun in great detail, down to features just 70km across, which the German team claim will be similar to what can be achieved in space.

Another unusual aspect of GREGOR is that it will operate in the open rather than a dome to allow the wind to cool the telescope’s structure and its mirrors. Its protective housing slides away to allow this.

The main mirror, or primary, is relatively lightweight and made from a material that does not change its shape under the heat of the brilliant Sun. It is also has a cooling mechanism added to the back of the primary to prevent it from heating up and producing image-distorting turbulence.

GREGOR, which will be open to use by astronomers from all over the world, was built by a German consortium led by the Kiepenheuer-Institut für Sonnenphysik in Freiburg with partners the Leibniz-Institut für Astrophysik Potsdam and the Max-Planck-Institut für Sonnensystemforschung in Katlenburg/Lindau.

Other contributions were made by the Instituto de Astrofísica de Canarias, the Institut für Astrophysik Göttingen, and the Astronomical Institute of the Academy of Sciences of the Czech Republic.

ESA: EUCLID Dark matter and bright solar observatory

ESA's Cosmic Vision 2015-2025 Plan is designed to give us new understanding and new views of the Universe.

Credits: NASA/ESA/ESO/W. Freudling (ST-ECF)

The powerful influence of the Sun and the nature of the mysterious 'dark energy' motivate ESA’s next two science missions.

Solar Orbiter and Euclid were selected today by ESA's Science Programme Committee for implementation, with launches planned for 2017 and 2019.

These two missions are medium-class missions and are the first in ESA's Cosmic Vision 2015-2025 Plan.
Solar Orbiter will venture closer to the Sun than any previous mission.

It is designed to make major breakthroughs in our understanding of how the Sun influences its environment, in particular how the Sun generates and propels the flow of particles in which the planets are bathed, known as the solar wind.

Solar activity affects the solar wind, making it very turbulent, and solar flares create strong perturbations in this wind, triggering spectacular auroral displays on Earth and other planets.

Solar Orbiter will be close enough to the Sun to sample this solar wind shortly after it has been ejected from the solar surface, while at the same time observing in great detail the process accelerating the wind on the Sun's surface. The mission's launch is planned for 2017 from Cape Canaveral with a NASA-provided Atlas launch vehicle. 

Dark energy is a mystery that reveals itself over the largest stretches of the Universe. 

ESA's Euclid mission will help unravel its mysteries.

Credits: European Space Agency, NASA, J.-P. Kneib (Observatoire Midi-Pyrénées) and R. Ellis (Caltech)

Euclid is designed to explore the dark side of the Universe.

Essentially a space telescope, the mission will map out the large-scale structure of the Universe with unprecedented accuracy.

The observations will stretch across 10 billion light years into the Universe, revealing the history of its expansion and the growth of structure during the last three-quarters of its history.

One of the deepest modern mysteries is why the Universe is expanding at an ever-accelerating rate. This cosmic acceleration must be driven by something that astronomers have named 'dark energy' to signify its unknown nature.

By using Euclid to study its effects on the galaxies and clusters of galaxies that trace the large-scale structure of the Universe, astronomers hope to be able to understand the exact nature of dark energy.

Euclid's launch, on a Soyuz launch vehicle, is planned for 2019 from Europe's Spaceport at Kourou, French Guiana.

Solar activity makes the wind of particles from the Sun turbulent. 

This can affect Earth by giving us aurora and disrupting radio communications.

ESA's Solar Orbiter will go closer to the Sun than any other mission to study the driving force behind solar activity.

"With the selection of Solar Orbiter and Euclid, the Science Programme has once more shown its relevance to pure science and to the concerns of citizens: Euclid will shed light on the nature of one of the most fundamental forces of the Universe, while Solar Orbiter will help scientists to understand processes, such as coronal mass ejections, that affect Earth's citizens by disrupting, for example, radio communication and power transmission," says Alvaro Giménez, ESA's Director of Science and Robotic Exploration.

Read more about ESA's Cosmic Vision and EUCLID on their portal

ESA funded EUCLID set to unlock the secrets of the Sun and dark energy

With funding from the UK Space Agency, space scientists and industry partners in the UK are set to benefit from two European Space Agency (ESA) projects - Euclid and Solar Orbiter.

The missions are part of ESA's Cosmic Vision programme and were originally selected from more than 50 missions.

They will be launched between 2017 and 2019. Solar Orbiter has now been officially adopted by ESA and will go forward immediately.

Euclid has been selected but has to complete its study phase before it can be fully adopted in June 2012.

Dr David Williams, Chief Executive of the UK Space Agency, said: "With strong UK involvement in these ambitious projects, we are set to maintain our country's position as a leader in space science within Europe.

These exciting missions are a prime example of collaboration between academia and the UK high-tech industry and will not only further our knowledge of space science but could help us unlock some of the greatest mysteries of our Universe."

Solar Orbiter is designed to travel closer to our own star than any previous Sun-watching mission. It will use an elliptical orbit to take it up to the Sun's higher latitudes to image, for the first time ever, the polar regions of our star.

This special path will also allow Solar Orbiter to keep pace with the Sun's rotation so that it can track specific features below it for several weeks at a time.

As it travels around the Sun, bombarded by the harsh solar wind, Solar Orbiter will carry out in-depth studies of the connections between the Sun and interplanetary space that could provide major breakthroughs in our understanding of how the inner Solar System is driven by solar activity.

The unique design of the spacecraft will allow it to withstand the scorching heat on the surface facing the Sun and the cold of space on the opposite surface, which would always remain in shadow.

Professor Tim Horbury from Imperial College London said: "Solar Orbiter is Europe's mission to the Sun. It will give us our first good view of the Sun's polar regions and by travelling closer in than Mercury, it will give us a unique close-up view of the Sun's atmosphere and how it blows off into space, past the Earth and into the far solar system."

NASA - Solar Storm Latest Images

NASA - Solar Dynamics Observatory