Solar System Things

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Mercury is Still Shrinking

For many years, scientists believed that Earth was the only tectonically active planet in the solar system. That changed after the Mercury Spacecraft, Messenger, did the first orbital mission at Mercury, mapping the entire planet and getting a look at the features on its surface.

Data revealed cliff-like landforms known as fault scarps. Because the fault scarps are relatively small, scientists are sure that they weren’t created that long ago and that the planet is still contracting 4.5 billion years after the solar system was formed.


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Pluto Has a Bizarre Atmosphere

Data from NASA’s New Horizons found 20 layers of atmosphere extending as high as 1,000 miles above the surface – higher than the Earth’s.

Pluto’s atmosphere is both cooler and more compact than expected. Tons of nitrogen gas escape the dwarf planet by the hour, but somehow Pluto is able to constantly resupply that lost nitrogen – most likely through geological activity.


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Rings Are Everywhere in the Solar System


We now know that every planet in the outer solar system, Jupiter, Saturn, Uranus and Neptune – each have ring systems. Rings are very different from planet to planet. Saturn’s spectacular rings, which may have come from a broken-up moon, are not repeated anywhere else.

Neptune has at least five main rings that we know of so far. This ring system has peculiar clumps of dust called arcs. The arcs are strange because the laws of motion would predict that they would spread out evenly rather than stay clumped together.