Ulysses begins polar exploration.At long last, Ulysses has reached its final destination. After nearly 4 years of sailing through the inner solar system, this spacecraft is now mapping uncharted solar territory Moving out of the plane in which the planets orbit the sun, Ulysses began in late June to study the star's polar regions polar regions: see Antarctica; Arctic, the.. Through December, the craft will orbit about 2.4 astronomical units astronomical unit (AU), mean distance between the earth and sun; one AU is c.92,960,000 mi (149,604,970 km). The astronomical unit is the principal unit of measurement within the solar system, e.g., Mercury is just over 1-3 AU and Pluto is about 39 AU from the sun. (AU) below the solar south pole South Pole, southern end of the earth's axis, lat. 90° S. It is distinguished from the south magnetic pole. The South Pole was reached by Roald Amundsen, a Norwegian explorer, in 1911. See Antarctica.; a similar sojourn above the north pole North Pole, northern end of the earth's axis, lat. 90°N. It is distinguished from the north magnetic pole. U.S. explorer Robert E. Peary is traditionally credited as being the first to reach (1909) the North Pole. In 1926, Richard E. Byrd and Floyd Bennett may have been the first persons to fly over the pole, but entries in Byrd's diary suggest that they may have missed the actual pole; if so, that feat would belong to Roald Amundsen. begins next June. (One AU is the average distance between Earth and the sun. From its unique vantage point some 70 [degrees] south of the sun's equator, Ulysses can study the south polar magnetic field An invisible energy emitted by a magnet. Same as flux., probe 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. The continuous expansion of the solar corona into the surrounding vacuum of space carries away from the sun about 1 million tons of gas per sec; this blows out like a wind through the solar system. at this location, and examine more fully the nature of the sun's upper atmosphere, or corona. Though the craft won't get its best view of the south pole until mid-September, the data already gathered hold several surprises, says Ulysses project scientist Edward J. Smith of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif. The craft hasn't yet found an increase in the strength of the magnetic field at the sun's south pole -- even though researchers believe that the field is most intense at the poles POLES - Polar Exchange at the Sea Surface POLES - Prospective Outlook on Long-Term Energy Systems. But Ulysses did find large variations over time in the field's direction. Scientists model magnetic fields as taut rubber bands; the time fluctuations may stem from waves generated in the bands by intense activity at the poles, Smith notes. The variations over time may explain why Ulysses didn't find an increase in the intensity of cosmic rays cosmic rays - Notionally, the cause of bit rot. However, this is a semi-independent usage that may be invoked as a humorous way to handwave away any minor randomness that doesn't seem worth the bother of investigating. "Hey, Eric - I just got a burst of garbage on my tube, where did that come from?" "Cosmic rays, I guess." Compare sunspots, phase of the moon. -- high-speed atomic nuclei arriving in the sun's vicinity from other parts of the galaxy Astronomers had expected the magnetic field to bend the path of incoming cosmic rays, thus enabling them to reach the poles more easily But the changes over time could weaken the field's ability to redirect the particles, Smith says. The craft also found that at the poles, the solar wind blows out from the sun twice as fast as it does at lower latitudes. This dovetails with evidence that the south pole has a large coronal 1. Of or relating to a corona, especially of the head. 2. Of, relating to, or having the direction of the coronal suture or of the plane dividing the body into front and back portions. |
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