As reported earlier this week, the Cassini spacecraft is now preparing to make a series of very close passes by the edges of Saturn’s rings, known as Ring-Grazing Orbits. A couple days ago, Cassini conducted a close flyby of Saturn’s largest moon Titan; this is the second-to-last ever flyby of Titan before Cassini enters the Grand Finale phase of its mission, culminating in a deliberate plunge into Saturn’s atmosphere on Sept. 15, 2017. During this flyby, Cassini focused on mapping the surface and surface temperatures and used Titan’s gravity to help place the spacecraft into the Ring-Grazing Orbits.
The Cassini mission to Saturn has been one of the most successful planetary missions ever, revealing the ringed giant and its moons as never before. Sadly, that mission is scheduled to end Sept. 15, 2017, and in preparation the spacecraft will be making some never-done-before maneuvers as it gets ready to take the final plunge into Saturn’s atmosphere on that date, aka the Grand Finale. Next week, Cassini will perform one of these feats, flying just past the edge of Saturn’s main rings.
Pluto, a tiny frigid world in the distant outskirts of the Solar System, has been full of surprises, as first revealed by the New Horizons spacecraft back in July 2015. Expected to be mostly a cold, geologically dead place, it has instead been shown to be quite the opposite. Yes, it’s bitterly cold of course, but New Horizons found ample evidence that it has also been geologically active in the past and in some ways still is. With tall mountains of solid water ice, ancient riverbeds carved by nitrogen rivers, vast plains, still-flowing glaciers of nitrogen ice, and possible ice volcanoes, Pluto is a wondrous world indeed. Another new finding makes it even more remarkable: evidence for a subsurface ocean of water. This had also been reported on previously by AmericaSpace, but the new update strengthens the case.
The Kepler K2 mission has now resumed after a delay of three days, NASA has reported. The Kepler Space Telescope is currently in Campaign 11, during which it is observing a total of 14,250 new targets, including the Galactic Center as well as two of Saturn’s moons, Enceladus and Titan.
To say that the New Horizons mission has been a success would be a massive understatement; this first-ever spacecraft to visit Pluto has revolutionized our understanding of this distant, small world. Pluto and its moons are complex and active places, more so than thought possible by most scientists. Even though New Horizons flew past Pluto instead of orbiting it in July 2015, it still collected an enormous amount of information, which has taken more than a year to be sent back to Earth. That process is now complete, NASA just announced.
As reported a few days ago, the Juno spacecraft orbiting Jupiter had entered safe mode, a precautionary turning off of all but vital instruments and other components when a software performance monitor induced a reboot of the spacecraft’s onboard computer. Now, Juno has successfully exited safe mode and is otherwise healthy and ready to continue its exploration of Jupiter.
NASA’s Juno spacecraft has been busy orbiting Jupiter and providing fantastic new views of this giant world, something not possible since the previous Galileo mission. While almost flawless so far, the mission has had a few hiccups recently. Juno entered safe mode just shortly before its next close flyby of Jupiter this week, apparently the result of a software performance monitor inducing a reboot of the spacecraft’s onboard computer. The spacecraft is otherwise healthy and Juno is conducting its own software diagnostics to determine the specific cause of the problem. Before this, Juno took its first observations deep into Jupiter’s turbulent atmosphere.
Water on Mars is one of the most talked about and controversial subjects in planetary science. It is now well-known that Mars used to be a much wetter place than it is now, although just how much water there was, and how long it lasted, is still a matter of considerable debate. Direct evidence from rovers, landers, and orbiters, including observations of ancient riverbeds, gullies, and lakes, has shown how at one time Mars was much more Earth-like than it is today. Rovers like Curiosity, Opportunity, and Spirit have actually driven over long-dried-up lakebeds, salty playa lakes, and regions of ancient geothermal activity such as hot steam vents. Now, the Opportunity rover is going to visit another feature not yet explored by any other rover or lander: a gully thought to have been carved by water millions or billions of years ago.
Ever since first landing in August 2012, the Curiosity rover has helped to revolutionize our understanding of Mars and has seen some incredible scenery along the way. It has travelled across an ancient lakebed and gazed at towering sand dunes and buttes, and now it is ready to begin the next phase in its mission: gradually ascending the lower slopes of Mount Sharp, the massive mountain sitting in the middle of Gale crater. The layers in the mountain will provide more clues as to how the Martian environment changed from being much wetter than it is now, to the dry but cold desert we see today. This next chapter in the rover’s mission is part of a two-year extension which began Oct. 1, 2016.
Intriguing new findings about Jupiter’s moon Europa were announced today by NASA, and while they don’t involve any direct evidence for life, they do provide more information on how scientists could better search for such evidence, without having to drill through the icy crust to the ocean below. The new observations, by the Hubble Space Telescope, have added to the evidence for active water vapour plumes on Europa – an exciting possibility, since they would possibly originate from the subsurface ocean, similar to the plumes on Saturn’s moon Enceladus. And just like the Cassini spacecraft has already done at Enceladus, those plumes – geysers really – could be sampled directly by a future spacecraft such as Europa Clipper.