High-resolution images of Pluto taken by NASA’s New Horizons spacecraft.
The plains on Pluto’s surface are composed of more than 98 percent nitrogen ice, with traces of methane and carbon monoxide. Nitrogen and carbon monoxide are most abundant on the anti-Charon face of Pluto (around 180° longitude, where Tombaugh Regio’s western lobe, Sputnik Planitia, is located), whereas methane is most abundant near 300° east. The mountains are made of water ice. Pluto’s surface is quite varied, with large differences in both brightness and color. Pluto is one of the most contrastive bodies in the Solar System, with as much contrast as Saturn’s moon Iapetus. The color varies from charcoal black, to dark orange and white. Pluto’s color is more similar to that of Io with slightly more orange and significantly less red than Mars. Notable geographical features include Tombaugh Regio, or the “Heart” (a large bright area on the side opposite Charon), Cthulhu Macula, or the “Whale” (a large dark area on the trailing hemisphere), and the “Brass Knuckles” (a series of equatorial dark areas on the leading hemisphere). Sputnik Planitia, the western lobe of the “Heart”, is a 1,000 km-wide basin of frozen nitrogen and carbon monoxide ices, divided into polygonal cells, which are interpreted as convection cells that carry floating blocks of water ice crust and sublimation pits towards their margins; there are obvious signs of glacial flows both into and out of the basin. It has no craters that were visible to New Horizons, indicating that its surface is less than 10 million years old.
Our Juno mission has been exploring Jupiter since July 2016 with a special passenger on board: JunoCam, an instrument designed to take spectacular close-up color images of the largest planet in our solar system. From the raw images, citizen scientists have processed a range of beautiful photographs that highlight Jupiter’s features, even turning them into works of art. Below, 10 stunning images JunoCam has given us over the past year.
1. Jovian tempest.
This color-enhanced image of a massive, raging storm in Jupiter’s northern hemisphere was captured by our Juno spacecraft during its ninth close flyby on Oct. 24, 2017. The storm is rotating counter-clockwise with a wide range of cloud altitudes, and the darker clouds are expected to be deeper in the atmosphere than the brightest clouds.
2. A southern stunner.
Jupiter’s southern hemisphere shows off in beautiful detail in this image taken on Oct. 24, 2017. The color-enhanced view captures one of the white ovals in the “String of Pearls,” one of eight massive rotating storms at 40 degrees south latitude on the gas giant planet.
3. Dreaming in color.
Artist Mik Petter created this unique digital piece using data from the JunoCam. The art form, known as fractals, uses mathematical formulas to create an infinite variety of form, detail, color and light. The original JunoCam image was taken on July 10, 2017.
4. Jovian moon shadow.
Jupiter’s moon Amalthea casts a shadow on the gas giant planet in this image taken on Sept. 1, 2017. The elongated shape of the shadow is a result of both the location of the moon with relation to Jupiter in this image as well as the irregular shape of the moon itself.
5. 95 minutes over Jupiter.
Once every 53 days, Juno swings close to Jupiter, speeding over its clouds. In about two hours, the spacecraft travels from a perch over Jupiter’s north pole through its closest approach (perijove), then passes over the south pole on its way back out. This sequence shows 11 color-enhanced images from Perijove 8 (Sept. 1, 2017) with the south pole on the left (11th image in the sequence) and the north pole on the right (first image in the sequence).
6. Soaring high.
This striking image of Jupiter was taken on Sept. 1, 2017 as Juno performed its eighth flyby. The spacecraft was 4,707 miles (7,576 kilometers) from the tops of the clouds of the planet at a latitude of about -17.4 degrees. Noteworthy: “Whale’s Tail” and “Dan’s Spot.”
7. In true color.
This true-color image offers a natural color rendition of what the Great Red Spot and surrounding areas would look like to human eyes from Juno’s position. The image was taken on July 10, 2017 as the Juno spacecraft performed its seventh close flyby of Jupiter.
8. The ‘face’ of Jupiter.
JunoCam images aren’t just for art and science—sometimes they’re created for a good chuckle. This image, processed by citizen scientist Jason Major, is titled “Jovey McJupiterface.” By rotating the image 180 degrees and orienting it from south up, two white oval storms turn into eyeballs, and the “face” of Jupiter is revealed. The original image was taken by the Juno spacecraft on May 19, 2017.
9. Bands of clouds.
This enhanced-color image of Jupiter’s bands of light and dark clouds was created by citizen scientists Gerald Eichstädt and Seán Doran. Three of the white oval storms known as the “String of Pearls” are visible near the top of the image. Each of the alternating light and dark atmospheric bands in this image is wider than Earth, and each rages around Jupiter at hundreds of miles (kilometers) per hour. The lighter areas are regions where gas is rising, and the darker bands are regions where gas is sinking. Juno captured the image on May 19, 2017.
10. The edge.
This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian “galaxy” of swirling storms. Juno captured this image on Feb. 2, 2017 and citizen scientist Roman Tkachenko enhanced the color to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. As a final touch, he rotated the image 90 degrees, turning the picture into a work of art.
NASA’s Cassini spacecraft will enter new territory in its final mission phase, the Grand Finale, as it prepares to embark on a set of ultra-close passes through Saturn’s upper atmosphere with its final five orbits around the planet.
Cassini will make the first of these five passes over Saturn at 12:22 a.m. EDT Monday, Aug. 14. The spacecraft’s point of closest approach to Saturn during these passes will be between about 1,010 and 1,060 miles (1,630 and 1,710 kilometers) above Saturn’s cloud tops.
On Sept. 11, a distant encounter with Titan will serve as a gravitational version of a large pop-down maneuver, slowing Cassini’s orbit around Saturn and bending its path slightly to send the spacecraft toward its Sept. 15 plunge into the planet.