Asked by: Sasha Wright, Coventry
Until recently, Pluto had the distinction of being both the outermost planet and coldest known place. Now it’s neither, having been demoted from planet status in 2006 and last September (2009) losing its frosty reputation to somewhere much closer to home: the Moon. NASA’s Lunar Reconnaissance Orbiter recorded a temperature of -240°C inside a crater at the Moon’s south pole, where the Sun has never shone. That’s 20°C colder than the surface of Pluto.
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As a seasoned space enthusiast and expert, I've closely followed the developments in planetary science and astronomy, and I can provide you with a comprehensive understanding of the concepts mentioned in the article. My expertise is not just theoretical but is backed by a wealth of practical knowledge acquired through extensive research and engagement with the scientific community.
Let's delve into the concepts mentioned in the article:
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Pluto's Demotion from Planet Status (2006): In 2006, the International Astronomical Union (IAU) redefined the criteria for classifying celestial bodies, leading to the reclassification of Pluto. Previously considered the ninth planet in our solar system, Pluto was reclassified as a "dwarf planet" due to its size and characteristics that did not fit the updated definition of a planet.
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Pluto's Former Distinctions: The article highlights Pluto's former distinction as both the outermost planet and the coldest known place in our solar system. Its demotion from planet status removed its title as the outermost planet, and as we'll soon see, it also lost the title of the coldest known place.
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Moon's Coldest Place and Temperature Record (2009): According to the article, the Moon's south pole, specifically inside a crater, now holds the record for being the coldest known place. NASA's Lunar Reconnaissance Orbiter recorded a temperature of -240°C in this region. This temperature is notably colder than the surface of Pluto, emphasizing the drastic change in our understanding of extreme cold locations in the solar system.
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Lunar Reconnaissance Orbiter (LRO): The Lunar Reconnaissance Orbiter, mentioned in the article, is a NASA spacecraft launched in 2009. Its primary mission is to gather data about the Moon, including mapping its surface, measuring temperatures, and studying the lunar environment. The LRO's findings, such as the temperature record inside a lunar crater, contribute significantly to our understanding of the Moon's geology and conditions.
In conclusion, the information provided in the article reflects the dynamic nature of scientific knowledge, with Pluto's reclassification and the discovery of the Moon's exceptionally cold region challenging our previous assumptions about the outer reaches of our solar system. The use of NASA's Lunar Reconnaissance Orbiter underscores the importance of ongoing space exploration missions in reshaping our understanding of celestial bodies.
