De zonsverduistering vanuit Angola
Monday, 02 July 2001
"I was leading a team of seven scientists for this eclipse, two from CLRC Rutherford Appleton Laboratory (including me), three from Queen's University in Belfast and two from the University of Wroclaw in Poland, where some of the equipment was made. We had been offered room on the roof of the Physics Department at the University of Zambia near Lusaka by Dr Habatwa Mweene, Head of the Physics Department, and the SECIS (Solar Eclipse Coronal Imaging System) equipment was set up there," said Ken.
The equipment consists of a pair of fast-frame CCD cameras, capable of operating at frame rates up to 60 or 70 per second, plus a small telescope and optics. This telescope includes a 'green line' filter (there is a bright spectral line due to Fe XIV (an ion of iron) in the coronal spectrum that this filter isolates) and a tracking mirror. This makes SECIS one of the fastest and most sophisticated astronomical digital cameras.
"We need this speed and sophistication to record subtle changes in the corona. We are almost certain that the magnetic fields, which are abundant in the Sun's atmosphere, are involved in the heating process, but scientists are intrigued to find out exactly how the process works," explains Ken. "When we arrived the weather was overcast and uninspiring, but by the day of the eclipse it had improved to offer ideal, cloudless conditions. There was a tremendous air of excitement among local people who had gathered at the University on various days throughout the week before. I gave a talk to 700 extremely enthusiastic youngsters and their teachers on 19 June, and it was thrilling for me to tell them about the eclipse and describe what they should look for -- they only vague impressions from newspaper and magazine reports. Unfortunately there was a desperate shortage of eclipse viewers and there were rumours that they were changing hands at £20 a time!"
Leading up to the eclipse images from both the TRACE and SOHO spacecraft clearly showed a new region rotating round on the sun's NE limb with associated prominences. The SECIS instrument does not view the whole corona, and seeing images from the spacecraft was important for the team to decide where to point the instrument. Both the CDS (one of the instruments on the SOHO satellite) experiment and instruments on the TRACE spacecraft were supporting the eclipse with images of the new region on the NE limb.
"I was extremely pleased not only to see the eclipse (my third, all under ideal weather conditions) but also to see the images coming up on our computer monitor during totality that showed everything was functioning well. It was a great moment," said Professor Phillips.
The team was filmed 'fly on the wall' style by John MacNish from Cirlevision who is putting together a BBC2 TV programme called Final Frontier. This will be screened on July 5 (starting half an hour after midnight) and repeated the following Sunday morning (at 7.45am) and might be screened the following Wednesday.
"I hope no embarrassing things will be shown!", commented Ken. The project was funded through the Particle Physics and Astronomy Research Council (PPARC), the Leverhulme Trust and Queen's University Belfast, as well as the FTS fund in 1997 which enabled us to buy the cameras. CLRC also provided financial help.
"I hope we will be able to capitalise on the enormous amount of data SECIS has collected. The heating of the sun's corona (and by implication of the coronae of all solar-type stars) is still unclear, so we hope that the data we collected over the last two eclipses will help us understand the question a lot better," said Ken.
Checkout the SECIS web pages for further information about the project.
=========================================================== SKY & TELESCOPE'S NEWS BULLETIN - JUNE 22, 2001 =========================================================== For images and Web links for these items, visit http://www.skypub.com ===========================================================
The shadow cast the country of Zambia in the limelight, which became a Mecca for eclipse-chasers from around the world. Thousands of them were drawn to Lusaka, its capital city, by prospects of clear skies, more than three minutes of totality, and relatively easy international access. Among them were more than 250 participants in the Sky & Telescope/Scientific Expeditions tour. Many were adding a second or third notch in their eclipse-chasing belts, but sprinkled among the group were veterans of more than a dozen eclipses and a large compliment of those experiencing their first taste of totality.
Conditions were virtually perfect at the observing site northwest of Lusaka, where the last vestiges of the Sun's disk slipped behind the Moon at 3:09 p.m. local time (13:09 UT). Cheers and shouts rang out as an exceptionally long diamond ring at the beginning of totality gave way to a brilliant, round corona spiked with several slender streamers that extended more than one degree from the Sun's limb. Electric-pink prominences were easily visible to the unaided eye near the beginning and end of totality.
After 3-1/2 minutes of darkness applause from the gathered crowd of about 300 signaled totality's end. "God's Gift. Magnificent!" exclaimed Joyce Smith a few moments after totality ended. "It made me feel so peaceful." She had traveled with her husband, Brian, from California to view her first eclipse. Moments later Stephen James O'Meara noticed the corona was still visible to the unaided eye when the emerging crescent of sun was blocked by the limb of a nearby tree. He and Sky & Telescope Senior Editor Dennis di Cicco report glimpsing the corona for another 6 minutes 55 seconds.
Additional eclipse reports and images.
What's Up in Space -- 22 Jun 2001
Jun. 21, 2001 Solar Eclipse Gallery
SPACE.com Bulletin -- Wednesday, June 20, 2001
SPACE.com: Live Coverage of Total Solar Eclipse from Africa
Rise and shine with SPACE.com! Comprehensive coverage of the Total Solar Eclipse 2001 begins tomorrow at 8:30 am EDT with live streaming video from Africa. The Total Solar Eclipse 2001 will not be viewable anywhere in the world, except in Africa and the next total solar eclipse visible in the Continental United States will not occur until 2017.
Beginning at 8:30 am EDT, SPACE.com will carry live streaming video from NASA TV of the African eclipse. The 2001 Solar Eclipse will reach totality at 9:12 am EDT tomorrow.
Space Weather News for June 20, 2001
NASA Science News for June 19, 2001
NASA Headquarters, Washington, DC
June 19, 2001
However, while the first total eclipse of the new millennium will not be visible from the United States, it will be made available live, from the Southern African nation of Zambia, to the rest of the world through NASA Television. The June 21st astral performance also is available to internet users who have high-speed internet connections.
Watching a total eclipse means different things to different people. Daylight fades in the middle of the day as the Moon slowly covers the face of the Sun, creating an eerie dusk as a shadow is cast on the Earth's surface.
Our ancient ancestors considered an eclipse to be a bad omen, and often carried out various rituals in an effort to scare away suspected evil forces that devoured the Sun. Today, scientists travel around the world to study this rare event and millions of people are satisfied to simply watch this celestial display of nature.
A science team will be in Zambia to capture video images of the eclipse using specially equipped telescopes. Besides being streamed live to the rest of the world, these images will be broadcast to about 110 participating museums and other venues.
This year, the event will focus on the themes of solar maximum, habitability of space and living with the Sun. "A total solar eclipse provides great opportunities to engage and inform the public about NASA's Sun -Earth Connection science and the effects of the active Sun in space and on Earth, " said Dr. George Withbroe, Science Director of the Sun-Earth Connection theme at NASA Headquarters, Washington, DC.
A message from the Expedition Two crew on board International Space Station is part of the webcast, which includes a conversation with American astronauts Jim Voss, Susan Helms and Russian Commander Yury Usachev.
NASA also will take viewers one million miles into space to see how scientists use artificially generated eclipses to study enormous solar eruptions. Scientific teams going to Africa for the eclipse will rely on the ESA-NASA Solar and Heliospheric Observatory (SOHO) spacecraft to show them the Sun's weather during the event.
Several NASA centers plan events associated and some of its Centers are planning comprehensive solar eclipse events:
To view the eclipse from a high-speed internet connection, visit the World Wide Web at: www.exploratorium.edu/eclipse
A complete list of participating museums can be found on the web.
NASA TV will carry the eclipse from 8:30 a.m. to 9:30 a.m. EDT. Stations carrying this feed are requested to super "Courtesy: NASA/Exploratorium." NASA TV can be found on GE-2, Transponder 9C, at 85 degrees West longitude, vertical polarization, with a frequency of 3880 MHz and audio of 6.8 MHz.
