| 阅读时间：3分10秒 P1： 研究新发现-a new radar study demonstrating that the core of the solar system’s innermost planet is at least partially molten 该研究影响： -settles a long-simmering debate -provide insight about how the solar system created its planets 传统观点：mercury ought to have cooled and solidified long ago. P2：探测发现质疑传统观点 -一方面Mercury has a magnetic field usually generated by the sloshing of charged material within a liquid core -另一方面the magnetic field is a remnant in the crust, frozen in place when Mercury’s core solidified. P3：新研究 -a close study of Mercury’s spin could determine whether the planet has fluid in its core -Solar gravity has a greater effect on a planet’s spin if the core is at least partially liquid. P4： 研究结果-variations in the spin were about double what would be expected if Mercury were solid 研究结论-t minimum, the outer core of Mercury—the boundary between the heart of the planet and its overlying mantle—must be liquid 旧观点-Mercury remains molten because sulfur infiltrated the planet’s iron core and lowered its melting temperature 新观点： -the high temperature would have kept sulfur as a vapor and so prevented it from being incorporated into the planet -Mercury, and perhaps other planets, grabbed sulfur and other material from beyond their immediate surroundings |
| 欢迎光临 ChaseDream (https://forum.chasedream.com/) | Powered by Discuz! X3.3 |