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SOUNDS OF THE SUN / VIDEO FILE RUNDOWN (Video to be uplinked on NASA TV Wednesday 2/21 at: 5:50 am; 12, 3, 6, 9 pm ET)
SYNOPSIS: Like listening to a heartbeat, scientists called helioseismologists are listening to the sound of the Sun to learn about its temperature, chemical makeup, and motions. An instrument aboard NASA’s Solar and Heliospheric Observatory (SOHO) watches the movements of the surface of the Sun to reconstruct the sound. Each pitch corresponds with a particular part of the Sun, allowing for various measurements and studies.
ITEM 1: THE ACTIVE SUN At a peak time in its 11-year solar cycle, the Sun is an extremely active star. The max period is reflected by the intense and consistent solar flares and coronal mass ejections (CMEs), some visible in this image from the Solar and Heliospheric Observatory (SOHO). While the Sun’s vibrations do not intensify during solar max, some of the frequencies change and the number of ‘bangs’ created by CMEs increase. SUPER: NASA / ESA TRT: :36
ITEM 2: SEEING THE SOUNDS This image from the Michelson Doppler Imager (MDI) instrument aboard SOHO clearly shows the surface motions of the Sun that are captured to create an audio track for the Sun. Because sound cannot travel through the vacuum of space, helioseismologists recreate it by speeding up the frequencies some 42,000 times and compress 40 days’ worth of vibrations into a few seconds. SUPER: NASA / ESA TRT: :17
ITEM 3: CLOSE-UP OF GRANULES This close-up reveals a small section of the solar surface where each granule is bigger than the state of Texas. They are part of a continuously changing network of convective cells that grow, fragment, decay, and explode like an earthly sonic boom within five minutes. This sends sound (pressure) waves throughout the Sun in millions of directions. SUPER: Swedish Vacuum Solar Telescope/Lockheed Martin TRT: 18
ITEM 4: SUNQUAKES Another correlation between Earth and the Sun: sunquakes. Solar flares (explosions on the surface) can also generate seismic disturbances on the surface and interior. Similar to throwing a pebble in a pond, the waves produced can shake the Sun to its very center and if on Earth, could measure up to 11.3 on the Richter scale. SUPER: NASA / ESA TRT: :10
ITEM 5: X-RAY VISION Superman’s X-ray vision is nothing compared to the MDI’s ability to see through the Sun to identify stormy solar weather up to a week in advance from the far side of the Sun. By watching the visible ripples on the Sun, scientists can see developing solar storms, called active regions. These regions are much larger than the Earth and consist of strong magnetic fields on the Sun’s surface; they are the origin of CMEs and solar flares. SUPER: NASA / ESA TRT: :28
ITEM 6: TUNES REVEAL TEMPERATURE Helioseismology relies on different sounds from different parts of the Sun, but some parts proved hotter (red) or cooler (blue) than expected. The finding was based on sound traveling faster in regions that are hotter, and slower in cool regions. This image is from MDI and VIRGO, both on the SOHO spacecraft. SUPER: NASA / ESA TRT:
ITEM 7: FOUNTAINS OF FIRE Why is the Sun's outer atmosphere, or corona, over one hundred times
hotter than the solar surface? These images from NASA's Transition
Region and Coronal Explorer (TRACE) spacecraft show the gas
fountains, or coronal loops responsible for heating the corona which
is also the starting point for solar eruptions. The loops are large enough
to span 30 planet Earths. TRT: :47
ITEM 8: MAGNETIC CARPET This animation shows the coronal loops in detail. Magnetic energy
rising up from bipolar loops interacts to produce electrical and
magnetic "short circuits". These magnetic fields that appear and
disappear within days, have a north and south pole connected by a
rising arch. They are replenished every 40 hours, vary in size, and
typically number about 50,000.
ITEM
9: SOLAR ROTATION / PLASMA RIVERS
ITEM 10: PULSING SUN Helioseismology revealed currents of gas deep inside the Sun, speeding and slackening every 16 months. In a March 2000 paper, scientists noted that the discovery was the first indication of changes close to the location of the solar dynamo. The dynamo is theoretical, believed to drive the 11-year solar cycle. When the lower gas speeds up, the upper gas slows and vice versa; the layers can differ by as much as 20% in six months. SUPER: NASA / ESA / NSF TRT: :28
ITEM 11: SUNSPOTS The MDI also studies sunspots, concentrations of strong magnetic flux with a lifetime of a few weeks. They appear darker due to a temperature of nearly half that of the solar surface. Sunspot activity tends to rise and fall in an 11-year cycle. They are important because their intense magnetic field powers events like solar flares and CMEs. SUPER: NASA / ESA TRT: :10
ITEM 12: TRACKING SOUND WAVES Like seismic waves on Earth, sound waves in the Sun do not travel in straight lines. The rays are bent and circle the solar interior in spherical shells or resonant cavities. SUPER: NASA / ESA TRT: :41
ITEM 13: SOLAR MAX Like the Earth, the Sun has seasons; we are currently in the middle of the highpoint, or "solar max". A two to three year period when the Sun's activity is most complex and turbulent, the solar max can be seen in the comparison of 1996 and 2000 solar images. While solar max does not change the sound heard by helioseismologists, it does influence the number of CMEs and flares heard. SUPER: NASA / ESA TRT:
ITEM 14: CMEs & SOLAR FLARES Among unanswered questions for helioseismologists: how are sunspots, solar flares and CMEs related to the motions in the solar interior? They hope to learn more about the solar activity cycle by better understanding the motions of the Sun. The plasma and radiation released by flares and coronal mass ejections (CMEs) can endanger astronauts, disrupt radio communication, and wipe out satellites. SUPER: NASA / ESA TRT: :45
ITEM 15: 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. SUPER: NASA / ESA TRT: :23
ITEM 16: MDI INSTRUMENT Sound waves from active regions propagate through the Sun's interior and bounce off the Sun's outer surface. The Michelson Doppler Imager (MDI) instrument on the SOHO spacecraft can detect the extremely subtle distortions these sound waves create on the Sun's surface. This data helps deduce the location of an active region on the far side of the sun. SUPER: NASA / ESA TRT: :10
ITEM 17: SCIENTIST B-ROLL
SUPER: NASA TRT: |
