Spacecraft to the sun: a probe named Ulysses takes a top-to-bottom look at our local star.It's only May, but Sun lovers everywhere are already basking in the Sun's glory - thanks to Ulysses, a robotic spacecraft A robotic spacecraft is a spacecraft with no humans on board, that is usually under telerobotic control. A robotic spacecraft designed to make scientific research measurements is often called a space probe. that's giving astronomers a whole new view of our local star. Ulysses recently became the first spacecraft to study the Sun from pole to pole Pole to Pole is an eight-part television documentary travel series made for the BBC and released in 1992. The presenter is Michael Palin, this being the second of Palin's major journeys for the BBC. . With a boost from Jupiter's powerful gravity, the spacecraft entered an orbit perpendicular to the ecliptic ecliptic (ēklĭp`tĭk, ĭ–), the great circle on the celestial sphere that lies in the plane of the earth's orbit (called the plane of the ecliptic). (the plane in which Earth and the other planets orbit). One of the biggest surprises from this solar polar expedition was the strength of the Sun's magnetic fields magnetic fields, n.pl the spaces in which magnetic forces are detectable; created by magnetostrictive ultrasonic scalers to cause the tips of instruments such as ultrasonic scalers to vibrate. . Astronomers have long known that the Sun, like Earth, has magnetic fields - areas over which it exerts magnetic force (an attraction or repulsion repulsion /re·pul·sion/ (re-pul´shun) 1. the act of driving apart or away; a force that tends to drive two bodies apart. 2. of certain materials). "You can think of the Sun's magnetic fields as roads that allow energy and matter to travel into space," says astrophysicist Shadia Habbal. Astronomers expected the Sun's magnetic fields to be strongest near the poles, the way the magnetic fields of Earth and bar magnets are. But Ulysses found that the Sun's magnetic fields don't follow this "normal" north-south pattern. Instead, their strength remains fairly constant all around the Sun (at least from Ulysses's vantage point in space). Astronomers are still trying to figure out the implications of this finding. Another surprise came out of Ulysses's measurements of 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 stream of electrically charged particles constantly emitted by the Sun. When the speed of the solar wind varies, the high- and low-speed particles collide and can cause disturbances in Earth's atmosphere “Air” redirects here. For other uses, see Air (disambiguation). Earth's atmosphere is a layer of gases surrounding the planet Earth and retained by the Earth's gravity. It contains roughly (by molar content/volume) 78% nitrogen, 20.95% oxygen, 0.93% argon, 0. . These disturbances sometimes interfere with telephone and radio communications and cause power failures. Unfortunately, Ulysses found that Earth lies right in the path of the stormiest solar wind. Nearer the Sun's poles, the solar wind is more steady and less likely to cause trouble. Too bad Earth's not in a polar solar orbit! Astronomers will continue to study Ulysses's findings. But you can discover more cool Sun facts right now just by turning the page |
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