Outer Solar System

Are Europa’s Plumes Really There?

December 22, 2014

A new study of data from the Cassini Saturn orbiter has turned up useful information about, of all places, Europa. Cassini’s 2001 flyby of Jupiter en route to Saturn produced the Europa data that were recently analyzed by members of the probe’s ultraviolet imaging spectrograph (UVIS) team. We learn something striking: Most of the plasma […]

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Rosetta: New Findings on Cometary Water

December 11, 2014

Where did the water in Earth’s oceans come from? It’s an open question, but new data from the Rosetta mission, in particular its ROSINA instrument (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) indicate that terrestrial water probably did not come from comets like 67P/Churyumov-Gerasimenko, around which Rosetta has been orbiting since August. There is […]

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Deep Space: Moving Toward Encounter Mode

December 9, 2014

No spacecraft has ever traveled further to reach its primary target than New Horizons, now inbound to Pluto/Charon. From 4.6 billion kilometers from Earth (four hours, 26 minutes light travel time), the spacecraft has sent confirmation that its much anticipated wake-up call from ground controllers was a success. Since December 6, New Horizons has been […]

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Our Best View of Europa

November 25, 2014

Apropos of yesterday’s post questioning what missions would follow up the current wave of planetary exploration, the Jet Propulsion Laboratory has released a new view of NASA’s intriguing moon Europa. The image, shown below, looks familiar because it was published in 2001, though at lower-resolution and with considerable color enhancement. The new mosaic gives us […]

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New Horizons: Potential KBO Targets Identified

October 21, 2014

The welcome news that the Hubble Space Telescope has found three potential Kuiper Belt targets for New Horizons means that our hopes for an extended mission may be fulfilled. Pluto/Charon is an exciting target, but how much better to use the spacecraft to visit a Kuiper Belt object as well, a member of that vast […]

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Mimas: An Intriguing Interior

October 20, 2014

I like what Radwan Tajeddine (Cornell University) has to say about recent work on Saturn’s moon Mimas. The lead author of a paper on the subject in Science, Tajeddine compares recent Cassini observations of the moon to a child shaking a wrapped gift, trying to figure out what the package conceals. ‘Shaking’ Mimas in a […]

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Titan: Polar Weather in Flux

October 2, 2014

Curiosities like the unusual feature in Ligeia Mare we discussed yesterday emphasize how important it is to have a long-term platform from which to study a planetary surface. If we are looking at something related to seasonal change on Titan, we have to remember that each season there lasts about seven Earth years. Winter turned […]

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A Surprise from Ligeia Mare

October 1, 2014

Interesting doings on Titan. I would guess that the odd feature that has cropped up in Ligeia Mare, a large ethane/methane sea in Titan’s northern hemisphere — has something to do with seasonal change, and that’s one possibility this JPL news release explores. After all, summer is coming to the northern hemisphere, and studying what […]

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New Horizons: Hydra Revealed

September 18, 2014

Since we don’t yet have flight-ready systems for getting to the outer Solar System much faster than New Horizons, we might as well enjoy one of the benefits of long flight times. Look at it this way: For the next ten months, we can look forward to sharper and sharper images and an ever increasing […]

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Crucible for Moon Formation in Saturn’s Rings

September 17, 2014

Hard to believe that it’s been ten years for Cassini, but it was all the way back in January of 2005 that the Huygens probe landed on Titan, an event that will be forever bright in my memory. Although the fourth space probe to visit Saturn, Cassini became in 2004 the first to orbit the […]

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