Yohkoh: a new X-ray view of the sun.High above the spinning sun, the solar atmosphere seethes with X-ray energy unleashed when dense magnetic field lines, twisted like taut rubber bands, suddenly snap or change their structure. Vast areas of the atmosphere erupt without warning; gases heated to millions of degrees Celsius send out spectacular flares that glow like fire at X-ray wave-lengths, forming giant arches and spewing out jets and ribbon-like streamers Streamers is a play by David Rabe.
The last in his Vietnam War trilogy that began with The Basic Training of Pavlo Hummel and Sticks and Bones into space.
That's the violent, X-ray view of the sun as seen by Yohkoh, a Japanese-built satellite launched last August. A team of U.S. and Japanese researchers last week presented still images and videotapes from the mission, culled from thousands of photos made during Yohkoh's first eight months in orbit. And judging by their audience's reaction last week, the videos would be sellouts at any rental outlet.
Many short-term rocket flights and a few satellites, including the Solar Maximum Mission This article is about the space satellite. For other uses, see SMM (disambiguation)
The Solar Maximum Mission satellite (or SolarMax) was designed to investigate solar phenomenon, particularly solar flares. It was launched on February 14, 1980. , have previously observed the sun's X-ray output, notes Keith Temple Keith Temple (born in Newcastle, England) is a British screenwriter for such shows as Emmerdale, Casualty and Doctor Who. He has also worked on the childrens' television programmes Children's Ward and Byker Grove. Strong of the Lockheed Palo Alto Palo Alto, city, California
Palo Alto (păl`ō ăl`tō), city (1990 pop. 55,900), Santa Clara co., W Calif.; inc. 1894. Although primarily residential, Palo Alto has aerospace, electronics, and advanced research industries. (Calif.) Research Laboratory. But Yohkoh has recorded more images of X-ray activity and traced the evolution of individual upheavals in the solar atmosphere in more detail than any other mission, he adds. Strong, his Lockheed colleague Marilyn E. Bruner and their collaborators presented their findings last week at a meeting of the American Astronomical Society The American Astronomical Society (AAS, sometimes pronounced "double-A-S") is a US society of professional astronomers and other interested individuals, headquartered in Washington, DC. in Columbus, Ohio Columbus is the capital and the largest city of the American state of Ohio. Named for explorer Christopher Columbus, the city was founded in 1812 at the confluence of the Scioto and Olentangy rivers, and assumed the functions of state capital in 1816. . They say the results are already providing researchers with new data for understanding the magnetic structures believed to trigger outbursts in the sun's outer atmosphere, or corona.
Comparison of visible-light and X-ray images taken by Yohkoh confirms previous observations that clusters of sun-spots-turbulent, optically dark regions of intense magnetic activity on the solar surface - coincide with the location of bright X-ray flares in the corona, says Bruner. Images of the corona taken with the satellite's two X-ray telescopes indicate that flares eject huge volumes of mass, comparable to the amount carried away in the same time period by the flow of charged particles known as the solar wind solar wind, stream of ionized hydrogen—protons and electrons—with an 8% component of helium ions and trace amounts of heavier ions that radiates outward from the sun at high speeds. , notes Hugh S. Hudson of the University of Hawaii (body, education) University of Hawaii - A University spread over 10 campuses on 4 islands throughout the state.
See also Aloha, Aloha Net. in Honolulu.
Rather than dying out rapidly, many of the observed flares last as long as half an hour, Bruner says. The Yohkoh images, she adds, suggest a mechanism for sustaining these outbursts, which trace out the looping patterns of magnetic field lines. Some newborn flares resemble arches that researchers suspect follow the path of tightly curved, stressed magnetic field lines that loop into and out of the corona like rubber bands near the breaking point. But as time goes on, the flares change shape, appearing as longer arches high in the corona. That transformation, says Bruner, suggests that the taut magnetic field lines have "uncoiled un·coil
tr. & intr.v. un·coiled, un·coil·ing, un·coils
To unwind or untwist or to become unwound or untwisted.
Adj. 1. ," releasing some of their energy and providing flares with a king of pilot light to continue burning at X-ray wavelengths.
A small, single flare may also trigger a chain reaction. Using Yohkoh's "hard" X-ray telescope, which records X-ray energies greater than 15,000 electron-volts, Takeo Kosugi of Japan's National Astronomical Observatory National Astronomical Observatory can mean: