The distant ice giant Uranus may not have been visited by a spacecraft since Voyager 2’s “Grand Tour” flyby in 1986 but the data gathered then is still being used today to make new discoveries. Most recently, researchers think they have found evidence of two previously unknown moons around Uranus, potentially bringing the planet’s count up…
Tag: moons
Watch Saturn’s Moons Race Inside the Rings
Round and round they go… the animation above, made from 14 raw images taken by NASA’s Cassini spacecraft on August 23, 2016, shows the moons Prometheus and Atlas orbiting Saturn within the Roche Division gap between its A (top right) and F (center) rings. The gravitational tug of Prometheus (92 miles / 148 km long) is strong…
Icy Nix Indicates Pluto’s Moons Are Leftovers From a KBO Collision
Recent findings from the New Horizons team reveal that Pluto’s third-largest satellite Nix is covered in the purest water ice yet observed in the dwarf planet system, even purer in spectra than what was seen on its slightly larger sibling Hydra. This analysis further supports the hypothesis that Pluto’s moons were created in an impact event…
Europa’s Icy Crust May Be Warmer Than We Thought
All the worlds may be ours except Europa but that only makes the ice-covered moon of Jupiter all the more intriguing. Beneath Europa’s thin crust of ice lies a tantalizing global ocean of liquid water somewhere in the neighborhood of 100 kilometers deep—which adds up to more liquid water than is on the entire surface of the Earth. Liquid…
Why Are Pluto’s Moons So Weird?
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 both orbit each other…
Rhea Eclipses Dione While Cassini Watches
It’s been a while since I last made one of these: it’s an animation comprising 27 images acquired by Cassini in various color channels on October 11, 2015. It shows Saturn’s second-largest moon Rhea passing in front of the smaller and more distant* Dione, both partially illuminated by sunlight. I cleaned up some image artifacts…
Dawn Finds Similarities Between Ceres and Saturn’s Moons
Around 600 miles wide, covered in craters and cliffs, a composition of rock and water ice… these are descriptions of both several of Saturn’s moons and the dwarf planet Ceres, based on recent observations by NASA’s Dawn spacecraft. New topographical maps show that, in terms of surface features anyway, Ceres shares similarities with Saturn’s icy…
Are You Ready For Pluto?
New Horizons sure is! With just over two weeks to go before the first-ever (and I repeat: EVER!) visit to Pluto and its family of moons the excitement has really ramped up exponentially, especially considering the increasingly detailed views of Pluto and Charon that the spacecraft has been capturing on approach. No longer just a…
Water Water Everywhere
Everyone knows that Earth is a “water-world,” with oceans covering 71% of its surface and at least as much contained within our planet’s mantle deep below its crust. But there’s also liquid water to be found elsewhere in the Solar System: on Mars, on the dwarf planets Ceres and Pluto, and also on the icy moons of Jupiter,…
What Will We Name the Features on Pluto? You Decide.
This July the New Horizons spacecraft will perform its long-awaited flyby through the Pluto system, capturing unprecedented data and images of the distant icy planet and its companion satellites Charon, Nix, Hydra, Kerberos, and Styx. The first two worlds, in particular, will have their surfaces seen in high-resolution, allowing scientists to observe and map their features…
Eppur Si Muove: Galileo’s Big Night
Note: This is an edited repost of an article from 2014. 405 years ago tonight, January 7, 1610, the Pisan astronomer Galileo Galilei looked up at a bright Jupiter at opposition through his handmade telescope and saw three little “stars” next to it, which piqued his natural scientific curiosity. He soon realized that these little…
Jupiter’s Moons Make Ghostly Auroral “Footprints”
We have all marveled at incredible photos and time-lapse videos of Earth’s auroral displays, captured by talented photographers that have braved the frigid nighttime temperatures of remote high-latitude locations as well as by those privileged few living in orbit aboard the International Space Station. But our planet isn’t the only one with curtains of light crowning its…
Lights in the Dark 