81P/Wild
Adapted from Wikipedia · Discoverer experience
Comet 81P/Wild, also known as Wild 2 (pronounced "vilt two"), is a comet that comes back to the inner Solar System every 6.4 years. It was named after the Swiss astronomer Paul Wild, who first saw it on January 6, 1978, using a special 40-cm Schmidt telescope in Zimmerwald, Switzerland.
For most of its long life—about 4.5 billion years—Wild 2 likely moved in a steady, far-out path around the Sun. But in September 1974, something big happened: the comet passed very close to the giant planet Jupiter. Jupiter's strong gravity changed Wild 2’s path dramatically. This event shifted the comet’s orbit from a slow 43-year cycle to a much quicker 6-year cycle, bringing it closer to the Sun.
Now, Wild 2 becomes visible from Earth roughly every six years, giving scientists and stargazers a chance to watch this icy traveler up close. Its journey offers valuable clues about the early Solar System, helping us learn about the building blocks of planets and other worlds.
Orbit
Before 1974, Comet 81P/Wild moved around the Sun every 43 years. It traveled very far from the Sun and then very close to it. In September 1974, the comet passed close to the planet Jupiter. Jupiter's strong gravity changed the comet's path, making its orbit shorter and bringing it closer to the Sun more often. Now, the comet completes its orbit around the Sun every 6.4 years.
Exploration
NASA launched the Stardust spacecraft on February 7, 1999. It flew by Wild 2 on January 2, 2004, collecting particle samples from the comet's coma. These samples, along with interstellar dust collected during the journey, were returned to Earth on January 15, 2006.
The close-up images showed the comet's surface had flat-bottomed depressions and sheer walls. Scientists analyzed the collected particles and found a variety of materials, including crystals that form at high temperatures. This suggests that parts of the comet were once much closer to the Sun than they are now.
Images
This article is a child-friendly adaptation of the Wikipedia article on 81P/Wild, available under CC BY-SA 4.0.
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