Recent research using data acquired by NASA’s Cassini spacecraft reveals that Titan is moving away from Saturn at a much faster rate than previously thought. How fast? Read on… “This result brings an important new piece of the puzzle for the highly-debated question of the age of the Saturn system and how its moons formed.”…
Tag: moons
New Theory Emerges on the Formation of Jupiter’s Galilean Moons
(From Caltech) During the first few million years of our sun’s lifetime it was surrounded by a protoplanetary disk made up of gas and dust. Jupiter coalesced from this disk and became encircled by its own disk of satellite-building material. This “circum-Jovian disk” was fed by material from the sun’s protoplanetary disk that rained down…
Why Are Pluto’s Moons So Weird?
(Updated post from 2016) Whether you call it a planet, a dwarf planet, or a Kuiper Belt or Trans-Neptunian Object—or all of the above—there’s no denying that Pluto and its family of moons are true curiosities in the Solar System. Not only does little Pluto have one moon, Charon, that’s so massive in comparison that they…
Ten More Moons For Jupiter!
Jupiter is the reigning heavyweight among the planets in our solar system so it just makes sense that it also possesses the most natural satellites. Over the past year I have been gleefully telling people that Jupiter has 69 moons (usually to a shocked response, occasionally to a giggling one) but now I must admit…
Eppur Si Muove: Galileo’s Big Night
On this night in 1610 the Pisan astronomer Galileo Galilei looked up at a bright Jupiter at opposition through his handmade telescope and noted three little “stars” next to it, piquing his natural scientific curiosity. Further observations over the next few nights showed that the planet wasn’t moving relative to the little “stars” as it…
How To Make A Moon: New Research Is Raising Questions On Our Moon’s Birth
There are a lot of moons in our solar system—175 major planet satellites, and three times that if you count every natural satellite of every known object (like asteroids)—but among them our own capital-M Moon is in many ways unique. At a full quarter the size of Earth, only Pluto has a moon so near…
These Are Our Best Pictures of Mars’ Smallest Moon
Mars isn’t a planet well-known for its natural satellites but it actually does have two small moons. The larger, Phobos, is an irregularly-shaped, heavily grooved and cratered world only about 17 miles (27 km) across at its widest. It orbits Mars so closely that it completes 3 orbits every day, and isn’t even visible from…
Iapetus: Saturn’s Stained Moon
Saturn’s “yin-yang” moon Iapetus (pronounced eye-AH-pe-tus) is seen in this image, a color composite made from raw images acquired by Cassini’s narrow-angle camera on March 11, 2017. The color difference on Iapetus is due to a fine coating of dark material that falls onto its leading hemisphere, sent its way by the distant moon Phoebe traveling within the recently-discovered giant diffuse…
OSIRIS-REx Captures a Picture of Jupiter from L4
NASA’s OSIRIS-REx may be designed to study asteroids close up but recently it’s captured a view of something farther away and much, much larger: the giant planet Jupiter and three of its largest moons at a distance of over 400 million miles! The image was taken on Feb. 12, 2017, when the spacecraft was 76 million…
Share Your Love of Cassini and Saturn with the World
Even if you’re feeling inundated by Valentine-themed everything at the moment, if you love space and you’re at all creative you’re definitely going to adore this. With Cassini in the final months of its 13 years at Saturn, NASA wants you to share your love of the spacecraft, its discoveries, and the ringed planet and its fascinating…
This is Jupiter Seen from Mars
The HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter (MRO) is specifically designed to take super high-resolution images of the surface of Mars but it also does a pretty darn good job capturing pictures of other objects too—like Jupiter and its Galilean moons, several hundred million miles away! The image above was captured in extended color (i.e. it…
Eppur Si Muove: Galileo’s Big Night, 407 Years Ago Today
407 years ago tonight, on January 7, 1610, the Pisan astronomer Galileo Galilei looked up at a brilliantly-shining Jupiter through his own handmade telescope and saw three bright little “stars” next to it, stirring his natural scientific curiosity. Further observations over the next several nights showed that the planet wasn’t moving relative to the little “stars” as it…
Lights in the Dark 