Very small worlds can do very big things—providing you’re willing to grade on a curve. Take the dwarf planet Ceres, the largest body in the asteroid belt, which is currently being orbited by the Dawn spacecraft. Ceres is just 591 miles (952 km) across—or 73% of the size of Texas—with only 3% of Earth’s gravity. If you weigh 150 lbs. here, you’d weigh 4.5 lbs. there.
But Ceres has a mountain—and it’s a whopper, as evidenced by this latest image sent home by Dawn, orbiting at an altitude of 915 miles (1,470 km). The mountain stands 4 miles (6 km) tall—a bit shorter than Mt. Everest, which tops out at 5.49 miles (8.83 km). But context is everything. A 4-mile-tall mountain on a tiny world like Ceres is the equivalent of a 49.8-mile-tall (80.1 km) mountain on Earth, or nine times taller than a pipsqueak like Everest. The Ceres mountain is not terribly active—at least as evidenced by the absence of debris at its base—but it is scored by a bright streak running down its side, which suggests some kind of dynamic processes at least in the past.
Every pixel of the Dawn image represents 450 ft. (140 m) of Ceres’ surface, which is already an impressively granular resolution. In the future, the spacecraft will approach the surface at just 25% of its current altitude, improving image detail dramatically. Whatever secrets Ceres is keeping Dawn may soon reveal.
Here are the Best Photos from Cassini's Mission to Saturn
The spinning vortex of Saturn's north polar storm on Nov. 27, 2012. Taken using a combination of spectral filters sensitive to wavelengths of near-infrared light. NASA/JPL/Space Science InstituteSaturn's lonely moon, Mimas on Nov. 30, 2004.AFP/Getty ImagesThe rings of Saturn captured by Cassini before it entered the orbit on 21 Jun. 2004.
SSPL/Getty ImagesA view of Saturn's moon Dione, taken during a close flyby on Jun. 16, 2015. NASA/JPL-Caltech/Space Science InstituteThe moons Titan, Mimas, and Rhea, captured by Cassini in this image released on Jun. 22, 2015.NASA/JPL-Caltech/Space Science InstituteA geyser basin at the south pole of Enceladus on Nov. 30, 2010. NASA/JPL-Caltech/Space Science InstituteA huge northern storm on Saturn In mid-Sept. 2004.Barcroft Media/Getty ImagesChasms on Dione. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 11, 2015. NASA/JPL-Caltech/Space Science InstitutePandora on the edge of Saturn's ring on Nov. 8, 2009.NASA/JPL/Space Science InstituteView of Saturn's rings as they surround the planet. Universal History Archive—UIG/Getty ImagesThe Earth and the moon photographed by NASA's Cassini spacecraft on Jul. 19, 2013.NASA/JPL-Caltech/Space Science InstitutePale, icy Dione, taken on Oct. 11, 2005.NASA/JPL/Space Science Institute—NASA/JPL/Space Science InstituteRed arcs in the northern area of Tethys on April 2015.NASA/JPL/Space Science InstituteAn aurora on Saturn.
The composite image was made from 65 individual observations by Cassini's visual and infrared mapping spectrometer on Nov. 1, 2008. The observations were each six minutes long.
NASA/SSPL/Getty ImagesThe Cassini spacecraft captured the storms at Saturn's north pole in this false color image released in April 2013. The storm appears dark red while the fast-moving hexagonal jet stream framing it is a yellowish green. Low-lying clouds circling inside the hexagonal feature appear in orange. A second, smaller vortex pops out in teal at the lower right of the image. The rings of Saturn appear in vivid blue at the top right.
NASA/JPL-Caltech/SSISaturn's moon Enceladus brightly reflects sunlight before a backdrop of the planet's rings.Universal History Archive/UIG/Getty ImagesThe Cassini spacecraft observed three of Saturn's moons set against the night side of the planet in this image from April 2011. NASA/JPL-Caltech/Space Science InstitutePhoebe, captured during Cassini's flyby on Jun. 11, 2004. NASA/JPL-Caltech/Space Science InstituteFive moons of Saturn dominated by Rhea in the foreground on Jan. 11, 2011.NASA/JPL/Space Science Institute—NASA/JPL/Space Science InstituteThe Cassini spacecraft takes one of its last good looks at Iapetus, a Saturnian moon.UIG/Getty ImagesSaturn's moon Hyperion, taken during a close flyby on May 31, 2015. This flyby marks the mission's final close approach to Saturn's largest irregularly shaped moon. NASA/JPL-Caltech/Space Science InstituteThe Cassini spacecraft captures a glimpse of the moon Atlas shortly after emerging from Saturn's shadow on Jan. 23, 2014.NASA/JPL-Caltech/Space Science InstituteMimas, Dione and Titan on May 27, 2015. The image is taken using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometersNASA/JPL/Space Science InstituteA swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings on Oct. 10, 2013.NASA/JPL