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Great success for the Helios Observing Team while the members of the team successfully observed the Total Solar Eclipse 11 July 2010 from beautiful Mangaia.

First images of the eclipse can be found at the team site:
http://tse2010.weebly.com/2010-eclipse.html
The very first images of the eclipse also published at SpaceWeather.com from the member of our team Constantinos Emmanouilidis.




Constantinos Emmanouilidis Says from Mangaia:
The Moon is now moving in front of the sun to produce a total eclipse over the South Pacific. The moon's shadow takes five hours to trace the 11,000 km path of totality. Along the way, sky watchers on Easter Island, the Cook Islands, the waters off Tahiti, and southern parts of Chile and Argentina will have the experience of a lifetime.

 
 
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Πέμπτη Ολική Έκλειψη Ηλίου για την ομάδα παρατήρησης                                            H.E.L.I.O.S

                            HellenicEclipseLaboratory for                                                               Imaging and Observing the Sun




Μετά από εκατοντάδες ώρες προετοιμασίας και σχεδιασμού πειραμάτων και τέσσερις Ολικές Εκλείψεις (1999 Βουλγαρία – Κωνσταντινούπολη, 2006 Καστελόριζο, 2008 Σιβηρία και 2009 Κίνα) η ομάδα HELIOS επιτέλους αναχώρησε για την νήσο Mangaia των Cook islands κοντά στην Γαλλική Πολυνησία. Από το μέρος αυτό θα διεξαχθεί πληθώρα πειραμάτων και μετρήσεων από έμπειρη ομάδα φοιτητών του τομέα αστρονομίας του Καποδιστριακού Πανεπιστημίου Αθηνών αλλά και ερασιτεχνών αστρονόμων από Αθήνα, Θεσσαλονίκη και Κύπρο.

Τον γενικό συντονισμό της ομάδος έχουν οι Μουσσάς Ξενοφώντας και Πρέκα Παπαδήμα Παναγιώτα, καθηγητές του Τομέα. Τον συντονισμό των πειραμάτων και μετρήσεων αλλά και τον σχεδιασμό αυτών έχει ο Στρίκης Ιάκωβος και Εμμανουηλίδης Κώστας , ερασιτέχνες αστρονόμοι.

Τα πειράματα , οι παρατηρήσεις και οι μετρήσεις που θα γίνουν αφορούν:
  • Την μορφολογική μελέτη του Στέμματος στο ορατό φάσμα κατά την πάροδο του 11ετούς Ηλιακού κύκλου.

  • Την μελέτη των μορφολογικών διαφορών του Στέμματος σε μήκη κύματος από τα 350nm (κοντινό υπεριώδες) μέχρι και τα 1000nm (μακρινό υπέρυθρο) με ειδικά φίλτρα στενού εύρους.

  • Την μελέτη του φάσματος της χρωμόσφαιρας το οποίο θα μας αποκαλύψει την ενεργειακή της κατάσταση σε σχέση με τις προηγούμενες χρονιές του Ηλιακού κύκλου.

  • Την μελέτη του φάσματος του Ηλιακού Στέμματος για την μέτρηση της θερμοκρασίας αυτού στις περιοχές του Ισημερινού και των πόλων.
Περισσότερες πληροφορίες για τις περιπέτειες της ομάδας μπορεί κανείς να δει στο site της ομάδας : www.tse2010.weebly.com

 
 
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Stunning  images and videos from the first light of SDO reveals the glory of our Star. Click on the links below!!

Launched on Feb. 11, 2010, SDO is the most advanced spacecraft ever designed to study the sun. During its five-year mission, it will examine the sun's magnetic field and also provide a better understanding of the role the sun plays in Earth's atmospheric chemistry and climate. Since launch, engineers have been conducting testing and verification of the spacecraft’s components. SDO will provide images with clarity 10 times better than high-definition television and will return more comprehensive science data faster than any other solar observing spacecraft.                                NASA-SDO










    SDO-First Light
   
http://sdo.gsfc.nasa.gov/assets/img/firstlight/movies/prominence20100330.mov
    http://sdo.gsfc.nasa.gov/assets/img/firstlight/movies/ar_multiwave_sm.mov
    http://sdo.gsfc.nasa.gov/assets/img/firstlight/thumbnails/multiwave_zm_thumb.jpg


 
 
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The Coordinated Modeling Center 's (CCMC) newest and most advanced space-weather science tool is the Integrated Space Weather Analysis (iSWA) system. The iSWA is a robust, integrated system provides information about space weather conditions past, present, and future and, unlike many other programs currently in use, has an interface that the user can customize to suit a unique set of data requirements. iSWA draws together information about conditions from the sun to the boundary of the sun's influence, known as the heliosphere. The iSWA systems digests information from spacecraft including the National Oceanic and Atmospheric Administration's (NOAA) Geostationary Operational Environmental Satellites (GOES), NASA's Solar Terrestrial Relations Observatory (STEREO), the joint European Space Agency and NASA mission Solar and Heliospheric Observatory (SOHO), and NASA's Advanced Composition Explorer (ACE).

The system compiles data about conditions on the sun, in Earth's magnetosphere -- the protective magnetic field that envelops our planet -- and down to Earth's surface. It provides a user interface to provide NASA's satellite operators and with a real-time view of space weather. In addition to NASA, the iSWA system is used by the Air Force Weather agency.

Access to space-weather information that combines data from state-of-the-art space-weather models with concurrent observations of the space environment provides a powerful tool for users to obtain a personalized "quick look" at space-weather information, detailed insight into space-weather conditions, as well as tools for historical analysis of the space-weather's impact.

Article from: http://www.sciencedaily.com/releases/2010/02/100223161837.htm
iSWA-HOME: http://iswa.gsfc.nasa.gov/iswa/iSWA.html

 
 
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The detector in the Extreme ultraviolet Imaging Telescope (EIT) on the SOHO spacecraft is a backside-thinned charge-coupled detector (CCD). The EIT CCD (above) is similar to the frontside CCD's handheld video cameras, but with better read noise (the "snow" or "fuzz" you see in your home videos when there's little available light) and, thanks to the backside-thinning, it's sensitive to extreme ultraviolet (EUV) light. For several days now bakeout procedure has started and data from EIT (Data live monitor) will not be available for a while.

In order to (i) keep read noise down (suppress the "snow") and (ii) prevent cosmic ray hits from permanently raising the read noise level by damaging the detector, the EIT CCD is usually operated at a temperature of about -67 C. This temperature is achieved by passive cooling: the CCD chip is thermally contacted to a titanium "cold finger" that is attached to a radiator plate that is pointed at a piece of sky perpendicular to the earth-Sun line. Unfortunately, there's a small amount of "slush," probably a mixture of water vapor and hydrocarbons, that avoided the initial bakeout (just after launch) of the instrument. The back end of the EIT telescope, unfortunately, is a difficult place from which to escape, because of the plate holding the final, thin aluminum filter just in front of the CCD, and a labyrinthine venting system (designed to prevent stray light). At -67 C, even with the low partial pressure in space, the slush condenses on the CCD and the cold finger --- they're the coldest parts of the back end of the instrument. The slush absorbs some EUV, and so reduces the thoughput of the instrument.

In addition, overexposure to EUV (say, from bright flares or --- before the onboard software was fixed to prevent this --- accidentally long exposures) can produce electron traps in the CCD material, which reduce the detector's throughput (how many electrons it produces for a given number of photons striking a pixel). Thus, we need to warm up --- "bake out" --- the detector to evaporate the slush (if only temporarily) and anneal out the traps in order to maintain the performance of the instrument.

We bake out the CCD by turning on small electric heaters on the CCD camera. This raises the CCD temperature to ~ +16 C. We do so every ~ 3 months, during SOHO telemetry keyholes, for 2 - 4 weeks; we also run detector efficiency tests before and after the bakeout. If nothing else, it gives our crack operations team some much-needed time off now and then. See the bottom of the EIT bakeout history for an estimate of how long the current bakeout will last.

For nearly three months in the summer of 1998, while the SOHO spacecraft rolled out of control, its batteries discharged and its solar panels pointing uselessly edge-on to the Sun, the radiator which normally carries heat away from the EIT CCD to the cold of space was pointed right at the Sun. According to the best thermal models available, this raised the temperature of the EIT CCD to over +35 C. Tests after the recovery of the spacecraft in 1998 September showed that not only had the CCD regained much of its lost sensitivity (~ 60%), but the "slush" appeared to have gone away --- for good. The CCD experts on the EIT team suspect that the slush began to escape when the rear thin aluminum filter peeled slightly from its frame in 1998 February. Still needed to bake out from time to time to cure the electron traps, however.

Source: http://umbra.nascom.nasa.gov/eit/CCD_bakeout.html

 
 
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Solar dynamics observatory will be ready for  launch in February 9/2010 on an Atlas V from SLC 41 at Cape Canaveral. SDO will fly three scientific experiments: Atmospheric Imaging Assembly (AIA), EUV Variability Experiment (EVE), Helioseismic and Magnetic Imager (HMI). This set of instruments will measure the extreme ultraviolet spectral irradiance of the Sun at a rapid cadence, measure the Doppler shifts due to oscillation velocities over the entire visible disk, make high-resolution measurements of the longitudinal and vector magnetic field over the entire visible disk, make images of the chromosphere and inner corona at several temperatures at a rapid cadence, make those measurements over a significant portion of a solar cycle to capture the solar variations that may exist in different time periods of a solar cycle. SDO's AIA instrument will have 1/2 greater image resolution than STEREO and 3/4 greater imaging resolution than SOHO. The image cadience also varies. SDO takes 1 image every .10 of a second. At best STEREO takes 1 image every 3 minutes and SOHO takes 1 image every 12 minutes.SDO will study how solar activity is created and how Space Weather comes from that activity. Measurements of the interior of the Sun, the Sun's magnetic field, the hot plasma of the solar corona, and the irradiance that creates the ionospheres of the planets will be also primary data products. SDO will help us to understand the how and why of the Sun's magnetic changes.

The scientific goals of the SDO Project are to improve our understanding of seven science questions:
  1. What mechanisms drive the quasi-periodic 11-year cycle of solar activity?
  2. How is active region magnetic flux synthesized, concentrated, and dispersed across the solar surface?
  3. How does magnetic reconnection on small scales reorganize the large-scale field topology and current systems and how significant is it in heating the corona and accelerating the solar wind?
  4. Where do the observed variations in the Sun's EUV spectral irradiance arise, and how do they relate to the magnetic activity cycles?
  5. What magnetic field configurations lead to the CMEs, filament eruptions, and flares that produce energetic particles and radiation?
  6. Can the structure and dynamics of the solar wind near Earth be determined from the magnetic field configuration and atmospheric structure near the solar surface?
  7. When will activity occur, and is it possible to make accurate and reliable forecasts of space weather and climate?
More info: http://sdo.gsfc.nasa.gov/

 
 
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   The importance of the solar cycle predictions is nowadays completely understood if we consider the factors that Space weather affect. Planning for satellite orbits and space missions often require the knowledge of solar activity years in advance to ensure the safety of the instruments and the astronauts. Just for the history we have to mention that Nasa will always remember the solar storm of August 1972 because it occurred between two Apollo missions. The crew of Apollo 16 had returned to Earth in April and the crew of Apollo 17 was preparing for a moon landing in December. Even thought the radiation dose inside the spaceship would not be lethal the astronauts who have been hypothetically outside of the spaceship might have absorbed 400 rem radiation lever not necessarily deadly but a quick trip back to Earth for medical care would be necessary.
    As for the last solar cycle predictions, we all remember the past predictions two or three years before. Past model predictions had indicated a major magnitude increase for the sunspot cycle 24. On the other hand new predictions mention that the new solar cycle will be extremely quiet compared to the last one. The new solar cycle have a starting time of October 2008 with minimum occurring in November or December 2008 and maximum in June 2013 with a maximum sunspot number of about 70 ± 18 or less for cycle 24. Past predictions  of 2007 predicted a start at March 2008 and peak in late 2011 or mid-2012. Half of the predictions showed a moderately strong cycle of 140±20 sunspots expected to peak in October of 2011 and the other half predicts a moderately weak cycle of 90±10 sunspots peaking in August of 2012.
More info according to the models used: http://solarscience.msfc.nasa.gov/predict.shtml

 
 
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The first solar eclipse of 2010 occurs at January 15th. The annular eclipse will be visible from a 300-km wide track that traverses central Africa, Indian Ocean and eastern Asia. Partial phases of the eclipse are visible primarily from Africa, Asia and Indonesia. The central track encounters land in the Maldive Islands at 07:26 UT. The capital city Male experiences an annular phase lasting 10m:45s. Unfortunately for east Europe the partial eclipse will merely be visible. As for Greece the moon shadow will cover only the 1/5 of the solar visible surface and Greek astronomers will be able to observe the second half of the eclipse although the sun will be near east horizon (~1deg-10deg). Remember that you should never look directly at the sun unless you use a special filter but in this case when the sun is low at the horizon is safe enough.    

    An annular eclipse occurs when the Sun and Moon are exactly in line, but the apparent size of the Moon is smaller than that of the Sun. Hence the Sun appears as a very bright ring, or annulus, surrounding the outline of the Moon. The Moon's orbit around the Earth is an eclipse, as is the Earth's orbit around the Sun; the apparent sizes of the Sun and Moon therefore vary. The magnitude of an eclipse is the ratio of the apparent size of the Moon to the apparent size of the Sun during an eclipse. An eclipse when the Moon is near its closest distance from the Earth (i.e., near its perigee ) can be a total eclipse because the Moon will appear to be large enough to cover completely the Sun's bright disk, or photosphere; a total eclipse has a magnitude greater than 1. Conversely, an eclipse when the Moon is near its farthest distance from the Earth (i.e., near its apogee) can only be an annular eclipse because the Moon will appear to be slightly smaller than the Sun; the magnitude of an annular eclipse is less than 1. Slightly more solar eclipses are annular than total because, on average, the Moon lies too far from Earth to cover the Sun completely. A hybrid eclipse occurs when the magnitude of an eclipse transitions during the event from smaller than one to larger than one—or vice versa—so the eclipse appears to be total at some locations on Earth and annular at other locations. (Source: http://en.wikipedia.org/wiki/)
 
 
The comet was found on Jan. 2nd by an Australian amateur astronomer Alan Watson, who was inspecting images obtained by STEREO-A's Heliospheric Imager on Dec. 30, 2009. This comet vaporised before his close approach
at the coronograph  occulting disk. Click at the following image  for video.
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This kamikaze comet is probably a member of the Kreutz sungrazer family. Named after a 19th century German astronomer who studied them in detail, Kreutz sungrazers are fragments from the breakup of a giant comet at least 2000 years ago. Several of these fragments pass by the sun and disintegrate every day. Most are too small to see. Today's fragment is a big exception. (SpaceWeather.com)
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Sungrazing comets have been observed for many years. In the late 1880's and early 1890's, Heinrich Kreutz studied the possible sungrazing comets which had been observed until then and determined that some were sungrazers and some were not. He also realized that those which were indeed sungrazers all followed the same orbit pattern. Actually, they were all fragments of a single comet which had broken up at the past. It is probable that the original comet, and its fragments, have broken up repeatedly as they orbit the sun with a period of about 800 years. In honor of his work, this group of comets is named the Kreutz sungrazers. At the right image you can see a diagram of January probable comet passage of Kreutz comets.

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Stephen William Hawking, Professor of Mathematics at the University of Cambridge as you all probable know.  Prof. Hawking will going to be main speaker of the 13  Greek Conference of EEF at Patras so i selected to present you some updates about his career.

At September Stephen stepped down from the Lucasian chair after a historic 30 years.  He will continue working at the University of Cambridge as Director of Research at DAMT. One month earlier at the White House, Professor Hawking was presented with a Presidential Freedom Award by United States President Barack Obama. The Presidential Freedom Award is America's highest civilian honour. Professor Hawking was among fifteen other recipients to have received the award, presented to individuals who make an especially meritorious contribution to the security or national interests of the United States, world peace, cultural or other significant public or private endeavors.
Other awards and honours of Stephen Hawking:
We all expect with great patience to see him at Patras and hear his fascinating speech!
More at http://www.patraseef.gr/