Tiny grains from the interior ocean of Enceladus


A quick holiday fund-raising campaign for Behind the Black!
 
Scroll down to read this post.
 
In past years I have managed to avoid asking for donations for Behind the Black during the holiday season. My finances however now compel me to do a short one-week fund-raiser, from November 11 to November 17.
 
I do not use Twitter for ethical reasons, which I have been told cuts down on traffic to the website. So be it. Furthermore, Facebook has clearly acted in the past two years to limit traffic to Behind the Black, almost certainly for political reasons. So be this as well. Finally, I do not post outside ads, as I have found them annoying to my readers and not that profitable to me.

 

Therefore, I need to ask for the direct support from my readers. If you like what I do here, please consider contributing, either by making a one-time donation or a monthly subscription, as indicated in the tip jar below.


 

Regular readers can support Behind The Black with a contribution via paypal:

Or with a subscription with regular donations from your Paypal or credit card account:


If Paypal doesn't work for you, you can support Behind The Black directly by sending your donation by check, payable to Robert Zimmerman, to
 
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

 

Or you could consider purchasing one of my books, as indicated in the boxes scattered throughout the website. My histories of space exploration are award-winning and are aimed for the general public. All are page-turners, and all not only tell the story of the beginning of the human exploration of space, they also help explain why we are where we are today. And I also have a science fiction book available, Pioneer, which tells its own exciting story while trying to predict what life in space will be like two hundred years in the future.

 

Note that for this week only I am also having a sale on the purchase of the last 20 hardbacks of Leaving Earth. (Click on the link for more information about the book, which was endorsed by Arthur C. Clarke himself!) This award-winning out-of-print book is now only available as an ebook, but I still have a handful of hardbacks available, normally for sale for $70 plus $5 shipping. For this week only you can buy them, personally autographed by me, for $50 plus $5 shipping! Just send me a check, payable to Robert Zimmerman, to the address above, with a note saying that the money is for the Leaving Earth hardback.

 

Please consider donating. Your help will make it possible for me to continue to be an independent reporter in the field of space, science, technology, and culture.

Using Cassini scientists have detected tiny grains of rock orbiting Saturn that they think were formed on the floor of the interior ocean of Enceladus and then spewed out its vents into space.

They believe that these silicon-rich grains originate on the seafloor of Enceladus, where hydrothermal processes are at work. On the seafloor, hot water at a temperature of at least 90 degrees Celsius dissolves minerals from the moon’s rocky interior. The origin of this energy is not well understood, but likely includes a combination of tidal heating as Enceladus orbits Saturn, radioactive decay in the core and chemical reactions.

As the hot water travels upward, it comes into contact with cooler water, causing the minerals to condense out and form nano-grains of ‘silica’ floating in the water. To avoid growing too large, these silica grains must spend a few months to several years at most rising from the seafloor to the surface of the ocean, before being incorporated into larger ice grains in the vents that connect the ocean to the surface of Enceladus. After being ejected into space via the moon’s geysers, the ice grains erode, liberating the tiny rocky inclusions subsequently detected by Cassini.

Additional data suggest that the interior of Enceladus is very porous, which means that interior ocean might not be one large bubble but a complex liquid-filled cave.

Share

2 comments

  • David M. Cook

    The only way to properly examine these worlds is for humans to actually go there and perform research from the surface. Robotic missions have their place, but for real scientists to obtain real data there’s no substitute for boots-on-the-ground programs. I wish more planetary scientists would push for manned missions to allow for a much more complete examination of our solar system.

  • Max

    “Cassini scientists also reported on the abundance of methane spewing into the atmosphere of Enceladus.”
    I believe this is what the oceans is made of, not water. Methane from the sun (main component of the solar wind) is plentiful and will freeze to all cold surfaces in layers over billions of years will become very thick. Methane will boil at -258F at one atmosphere. (turns into a liquid at near 300° below zero at one atmosphere) not much heat required to cause outgassing. Once the methane is exposed to the cold of space, it will refreeze to the surface or Sublimes from near orbit. The pressure of the ice on top pushing down, combined with tidal forces will provide enough heat to do the job.
    As for the dust grains spewing into space, the measurement of 2 to 8 nanometers seems excessively small. Bacteria is 5 to 20 micrometers in size. Viruses are 30 to 50 nm. small. 20 large Atoms lined up is about 2 nanometers long. It is very difficult to measure the dust grains that are smaller than the wavelength of visible light.
    On the other hand, the dust grains in heavy concentrations will block light just like looking at city smog through miles of atmosphere makes it visible.
    I too think we need to send someone there to study it directly. I barely remember the lunar landing as a child, I truly thought man would be living on the moon by now…

Leave a Reply

Your email address will not be published. Required fields are marked *