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Jason DavisJanuary 17, 2020

The Downlink: Ganymede's North Pole, A New Asteroid to Explore

Ganymede's North Pole

NASA / JPL-Caltech / SwRI / MSSS / Image processing by Gerald Eichstädt

Ganymede's North Pole
NASA’s Juno spacecraft captured these images of Jupiter’s moon Ganymede at a distance of roughly 100,000 kilometers during a flyby of Jupiter on 25 December 2019. They are the first-ever images of Ganymede’s north pole.

Welcome to The Downlink, a planetary exploration news roundup from The Planetary Society!  Here's everything that crossed our radar this week.

Jupiter NASA’s Juno spacecraft recently captured the first-ever north pole images of Jupiter’s moon Ganymede. JunoCam, a webcam-like instrument aboard the spacecraft, took the photos on 25 December 2019 at a distance of roughly 100,000 kilometers as Juno performed its 24th close flyby of Jupiter. Like Europa and Callisto, Ganymede probably has a subsurface ocean. The moon is larger than Earth’s moon. See more images of Ganymede in our image library

Didymos The Hubble Space Telescope has detected that Eurybates, an asteroid targeted for flyby by NASA’s Lucy spacecraft in 2027, has a small moon. Eurybates is a Trojan asteroid; Trojans cluster into two groups that share Jupiter’s orbit around the Sun. (The asteroids that lead Jupiter in its orbit, such as Eurybates, are traditionally named for Greek heroes; those that trail Jupiter are named for Trojan heroes.) Lucy launches in 2021 on a mission to visit 7 asteroids—now 8 if you count Eurabytes’ newly discovered moon.

Earth NASA welcomed 11 new astronauts into its ranks, following a graduation ceremony for its 2017 astronaut candidates. They include geologist Jessica Watkins and geobiologist Zena Cardman, who spoke with The Planetary Society after their selection as candidates in 2017. Two Canadian Space Agency astronauts also graduated, having trained alongside their NASA counterparts. The astronauts’ graduation means they are now available for active missions. 

Saturn The European Space Agency celebrated the 15th anniversary of its Huygens spacecraft landing on Saturn’s moon Titan. Our solar system specialist, Emily Lakdawalla, reported on that 2005 landing live from the European Space Operations Centre in Darmstadt, Germany. ESA used the anniversary to announce they had solved a long-standing mystery of why the probe spun in the wrong direction during descent. Relive the descent in this video that reconstructs the timeline of telemetry and images from Huygens.

Mars NASA’s Mars 2020 rover is one step closer to getting a name. Potential names for the rover, which will launch in mid-2020 to search for signs of past life on Mars, were submitted by U.S. schoolchildren. There are 155 finalist names remaining; the pool will be narrowed to 9 in late January. Learn more about the Mars 2020 mission here.

Earth NASA Astronauts Christina Koch and Jessica Meir completed a seven-and-a-half-hour spacewalk outside the International Space Station to replace batteries for the station’s solar arrays. Astronauts have been replacing the station’s aging nickel-hydrogen batteries with newer, more powerful lithium-ion batteries. A final spacewalk is planned next week. Watch a video showing how the spacewalk worked here.

Mars The European Space Agency reports its ExoMars rover completed environmental testing in Toulouse, France. The rover, named after DNA scientist Rosalind Franklin, will launch in July or August. On Mars it will drill for samples up to 2 meters beneath the surface, searching for signs of past and present life.

Exoplanet NASA’s Spitzer Space Telescope will retire at the end of January. Launched in 2003, the observatory was designed to study the universe in infrared light. Among Spitzer’s claim to fame is the discovery of 5 of the 7 Earth-size exoplanets found around the star TRAPPIST-1.

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Read more: Mars 2020, Spitzer Space Telescope, Ganymede, ExoMars 2020, astronaut, L4 Trojan 3548 Eurybates, extrasolar planets, International Space Station, Mars, The Downlink, Juno

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Jason Davis

Editorial Director for The Planetary Society
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