2001 SPACE SCIENCE VIDEOTAPES |
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Tape Title | Record ID | Date Produced | TRT: |
Synopsis |
| STORMY SPACE WEATHER TAKES A TOLL ON OZONE | G01-056 | 07/31/01 | 00:06:47 | Electrically charged particles that rain down on Earth's atmosphere from large solar storms help to deplete upper-level ozone for weeks to months, according to a new study. Based on observations from one of the largest solar events of recent years, the July 14-16,2000 "Bastille Day" flare, solar protons react with the atmosphere in much the same way as CFCs and other natural elements. While the process breaks down important ozone molecules, the bulk of the reduction occurs in the uppermost atmospheric layer where only a small portion of the protective ozone layer resides.
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TAPE CONTENTS: |
| ITEM (1): Bastille Day Flare And Proton Event - The July 14, 2000 coronal mass ejection from the Sun stands as one of the most powerful solar events in recent years. This view shows the solar flare (explosion) taking place on the Sun as seen by the EIT instrument aboard the SOHO spacecraft. What follows the flare is a storm of positively charged particles (protons) which bombard the imager of the instrument. It is these protons that break up molecules of nitrogen and water vapor that react with ozone molecules to deplete the ozone layer.
Courtesy: NASA/ESA
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| ITEM (2): Protons Hit The Cameras - The LASCO instrument aboard the SOHO spacecraft saw these two views of the solar proton event on July 14, 2000. The particles reached the spacecraft in less than one half-hour and continued pelting it for days. LASCO studies the Sun's corona by blocking out the actual Sun with an artificial eclipse. The Sun's size is represented by the inset image in the inner circle.
Courtesy: NASA/ESA
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| ITEM (3): Protons Bombard The Earth - The following sequence shows the Bastille Day flare proton event as seen by the Polar spacecraft overlooking Earth. Over three hours, the number of protons arriving increased until the image of Earth was completely hidden. The resulting aurora was seen as far south as Texas.
Courtesy: NASA
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| ITEM (4): The Ozone Hole - The year 2000 marked the largest Antarctic hole ever observed. Scientists have determined that a marginal amount of the ozone layer is depleted following a series of processes that starts with the protons released from solar flares and coronal mass ejections from the Sun. The ozone layer is crucial for protecting the Earth from harmful UV radiation and is often representative of climate change due to both natural and man-made efforts.
Courtesy: NASA
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| ITEM (5): What Is a CME? - Coronal Mass Ejections (CMEs) are violent discharges of electrically charged gas from the Sun's corona, usually the result of a solar flare (explosion). The largest explosions in the solar system, CMEs launch up to 10 billion tons of ionized gas into space at speeds of one to two million miles an hour.
Courtesy: NASA
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| ITEM (6): Where Is The Affected Ozone? - The animation reveals three of the four atmospheric layers: the mesosphere, stratosphere and troposphere. Scientists determined that these proton events affect up to 70 percent of the ozone in the middle mesosphere and about nine percent of the ozone in the upper stratosphere. Because the vast majority of the ozone layer resides in the middle and lower stratosphere, less than one percent of total ozone loss is due to the proton events.
Courtesy: NASA
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| ITEM (7): The Chemistry of It All - This process is similar to the chemical breakdown of ozone from pollutants like chlorofluorocarbons (CFCs). When the solar protons bombard the upper atmosphere, they break up molecules of gases like nitrogen and water vapor. Once freed, those atoms react with ozone molecules and reduce the layer.
Courtesy: NASA
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| ITEM (8): SOHO Spacecraft - The Solar and Heliospheric Observatory (SOHO) orbits the Sun at a location approximately one million miles from Earth to gain an unobstructed view of the Sun. It carries 12 instruments and is a joint NASA / European Space Agency (ESA) mission.
Courtesy: NASA/ESA
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| ITEM (9): POLAR Spacecraft - Launched in February 1996, NASA's Polar spacecraft makes daily passes over Earth's north and south poles in order to study the Earth's magnetosphere and auroras that can result from solar storms.
Courtesy: NASA
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| ITEM (10): UARS Spacecraft - Launched in 1991 and set to be decommissioned in 2001, the Upper Atmosphere Research Satellite (UARS) has surpassed its lifespan by eight years. One of 10 instruments aboard UARS, the Halogen Occultation Experiment (HALOE) instrument allowed for the study of ozone in the stratospheric layer of the Earth's atmosphere.
Courtesy: NASA
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