Is Pluto a Planet?Though small and very far from the Earth, we've always thought of Pluto(冥王星) as the ninth planet in our solar system; however, there has beendebate among astronomers about Pluto's validity as a planet.Most people do in fact consider it a planet thinking t bizarre ...
数十年来，科学家普遍认为太阳系有九大行星，但随着一颗比冥王星更大、更远的天体的发现，使得冥王星大行星地位的争论愈演愈烈。一是由于其发现的过程是基于一个错误的理论；二是由于当初将其质量估算错了，误将其纳入到了大行星的行列。因此在国际天文学联合会大会上，是否要给冥王星“正名”成为了大...
1. What Is a Planet? : Is Pluto a Planet? A Historical Journey through the Solar SystemWeintraubDavid A
Regardless of whether Pluto is a planet or a dwarf planet, it remains a fascinating part of the solar system, from its huge white "heart" of frozen nitrogen to the ice-spewing 'supervolcano' thought to lurk below its surface. "Pluto hasn't changed," Margot said. "It's just as exciting...
On August 24, 2006, at the 26th General Assembly of the International Astronomical Union (IAU) in Prague, by a majority vote of only the 424 members present, the IAU (an organization of over 10,000 members) passed a resolution defining planet in such a way as to exclude Pluto and ...
an age-old debate about what is and what is not a planet. One of many sizeable hunks of rock and ice in the Kuiper Belt, Eris has resisted easy classification and inspired much controversy over the definition of planethood. But, Pluto itself has been subject to controversy since its ...
The International Astronomical Union (IAU) downgraded the status of Pluto tothat of a dwarf planet because it did not meet the three criteria the IAU uses to define afull-sized planet Essentially Pluto meets all the criteria except one-t "has not clearedit neighboring region of other objects....
This would make Pluto a planet again, but it would do the same to the Earth's moon as well as many other moons in the solar system, and bring the total number of officially recognized planets up to 110. A year later, Stern, along with planetary scientist David Grinspoon, wrote an ...
Is Pluto a planet? Does it qualify? For an object to be a planet, it needs to meet these three requirements defined by the IAU:It needs to be in orbit around the Sun –Yes, so maybe Pluto is a planet. It needs to have enough gravity to pull itself into a spherical shape –Pluto...
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