Astronomers have found a unique object that appears to be made of inner Solar System material from the time of Earth’s formation, which has been preserved in the Oort Cloud far from the Sun for billions of years. Observations with ESO’s Very Large Telescope, and the Canada France Hawai`i Telescope, show that C/2014 S3 (PANSTARRS) […]
Caltech researchers have found evidence of a giant planet tracing a bizarre, highly elongated orbit in the outer solar system. The object, which the researchers have nicknamed Planet Nine, has a mass about 10 times that of Earth and orbits about 20 times farther from the sun on average than does Neptune (which orbits the […]
Long before Mercury, Venus, Earth, and Mars formed, it seems that the inner solar system may have harbored a number of super-Earths–planets larger than Earth but smaller than Neptune. If so, those planets are long gone–broken up and fallen into the sun billions of years ago largely due to a great inward-and-then-outward journey that Jupiter […]
The closest planet to the sun appears to get hit by a periodic meteor shower, possibly associated with a comet that produces multiple events annually on Earth. The clues pointing to Mercury’s shower were discovered in the very thin halo of gases that make up the planet’s exosphere, which is under study by NASA’s MESSENGER […]