Tag Archives: plumes

Water plumes on Europa?

New data from the Hubble Space Telescope suggests that there might be active water plumes issuing from Europa that are fed by the planet’s underground ocean.

In 10 separate occurrences spanning 15 months, the team observed Europa passing in front of Jupiter. They saw what could be plumes erupting on three of these occasions.

This work provides supporting evidence for water plumes on Europa. In 2012, a team led by Lorenz Roth of the Southwest Research Institute in San Antonio, detected evidence of water vapor erupting from the frigid south polar region of Europa and reaching more than 100 miles (160 kilometers) into space. Although both teams used Hubble’s Space Telescope Imaging Spectrograph instrument, each used a totally independent method to arrive at the same conclusion.

These results are very very uncertain. As the lead scientist noted twice during the press conference, the data is at the very limits of Hubble’s capabilities. I would not be surprised at all if later observations find that it is in error.

In fact, the press conference itself was more a PR event to lobby for Hubble as well as the James Webb Space Telescope than it was a description of a new discovery. The discovery itself was given a much bigger tease than it really deserves, considering the very uncertain nature of its data. I am a big fan of Hubble, as anyone who has read anything I have written in the past two decades. Nonetheless, I find this blatant lobbying very annoying. Also very annoying will be the naive willingness of many in the press to buy into this story. Expect a lot of silly stories today and tomorrow screaming that water jets coming from Europa have been definitely photographed by Hubble.


Comet 67P/C-G’s plumes

plumes from Comet 67P/C-G

The science team running Rosetta has released an image (cropped by me on the right) from the probe’s high resolution camera showing the fine structure of Comet 67P/C-G’s plumes.

I call them plumes rather than jets, which is the word the scientists use as well as everyone else, because it appears to me that they really aren’t jets, tightly confined flows of material coming from a nozzle-like opening. Instead, the image makes me think of very fast-rising plumes of smoke rising from an extinguished fire.

This image was taken in November, and is one of only a very tiny handful of images released from the high resolution camera. Rosetta’s science team has been very possessive of images from this camera, holding them back for their own research papers to follow in the future. Even here, the image is not very detailed. I wonder what cool stuff this camera has snapped close in that they have not yet shown us.