Hinode helps unravel long-standing solar mysteries (Forwarded)

ESA News
http://www.esa.int

22 August 2007

Hinode helps unravel long-standing solar mysteries

A year after launch, scientists working with Hinode, a Japanese mission with
ESA participation, are meeting at Trinity College, Dublin, to discuss latest
findings on solar mysteries -- including new insights on solar flares and
coronal heating.

Highlights include new insights on the workings of solar flares and on the
mechanism behind coronal heating.

Hinode (Sunrise in Japanese) was launched to study magnetic fields on the
Sun and their role in powering the solar atmosphere and driving solar
eruptions. With its Extreme Ultraviolet Imaging Spectrometer (EIS),
effectively a solar speed camera, it is now possible to pinpoint the source
of eruptions during solar flares and to find new clues about the heating
processes of the corona.

The speed camera is a spectrometer, an instrument that splits the light
coming from solar plasma, a tenuous and highly variable gas, into its
distinct colours (or spectral lines), providing detailed information about
the plasma. The velocity of the gases in a solar feature is measured by the
Doppler effect -- the same effect that is used by police radars to detect
speeding motorists.

"Hinode is an impressive example of international cooperation and is now
helping us solve the mysteries of the Sun with spectacular new data," says
Bernhard Fleck, ESA's Hinode and SOHO project scientist.

Keith Mason, of the Science and Technology Facilities Council (STFC) said,
"Our Sun is a dynamic and violent entity and European astronomers have
played a crucial role in understanding it; right from the first observation
of a solar flare to present-day work to predict and protect against the
Sun's outbursts."

Solar flares, massive energetic explosions that rise up from the Sun, can
damage manmade satellites and pose a radiation hazard to astronauts. Despite
decades of study, many aspects of this phenomenon are not well-understood.
Hinode's observations are now shedding light on possible mechanisms that
accelerate solar particles in flares.

Louise Harra at the Mullard Space Science Laboratory, University College
London, leading the EIS team says, "We knew that solar flares can impact a
vast area on the Sun, sometimes leaving behind mysterious 'dark patches'.
Using Hinode, for the first time we have been able to train a speed camera
on the material in these dark areas -- which can be twenty times the
diameter of the Earth."

"We have witnessed material flowing from the dark patch in the wake of the
flare, feeding the particle flow that can be hazardous for anything in its
path as it hurtles through space at 2000 times the speed of a fighter
plane."

These dark areas fade away after the flare, over several days. "In the long
term, understanding solar storms in this new level of detail will allow us
to make better predictions of 'space weather' storms. This is critical for
satellite telecommunications, which we now take for granted", she adds.

Ichiro Nakatani, JAXA Project Manager for Hinode commented, "We are
delighted that nearly a year after launch, we are discovering new things
about our nearest star, with many more discoveries to come. The years of
hard work that went into developing the satellite were definitely worth it."

Notes for editors:

The Hinode Science meeting is taking place at Trinity College Dublin from 20
to 24 August, and is hosted by the Solar Physics team. The team is led by
Peter Gallagher and is funded by Science Foundation Ireland and ESA.

Hinode is a Japanese mission developed and launched by ISAS/JAXA, with NAOJ
as domestic partner and NASA and STFC as international partners. It is
operated by these agencies in co-operation with ESA and the Norwegian Space
Centre.

Since 27 May 2007, European scientists have free access to spectacular data
and images from Hinode. This free access is possible thanks to the opening
of the Hinode Science Data Centre in Norway, developed and run by the
Institute of Theoretical Astrophysics at the University of Oslo on behalf of
ESA and the Norwegian Space Centre. It is part of ESA and Norway's joint
contribution to this solar mission.

The other part of the joint contribution to Hinode consists of ground
station coverage through the SvalSat downlink station at Svalbard, which
nearly quadruples the data rate and thus significantly increases Hinode's
science return. Svalsat is the only station in the world that can receive
Hinode's data during each of its 15 daily orbits.

Hinode's operations centre is located at JAXA's facility in Sagamihara,
Japan.

For more information:

Bernhard Fleck, ESA SOHO and Hinode Project Scientist
Email: Bfleck @ esa.nascom.nasa.gov

Pal Brekke, Senior Advisor, Norwegian Space Centre
Email: Paal.Brekke @ spacecentre.no

[NOTE: Images supporting this release are available at
http://www.esa.int/esaCP/SEMKOOWZK5F_index_1.html ]