Category Archives: planetary science

cassini mission, saturn, Titan

One Shimmery Lake

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Titan Has a Liquid Lake: is this News?  Yeah!!

A flash of sunlight glints off a lake on Titan, one of the moons of Saturn. Courtesy NASA and the Cassini Equinox Mission.
A flash of sunlight glints off a lake on Titan, one of the moons of Saturn. Courtesy NASA and the Cassini Equinox Mission.

I know this hit the news a few days ago, but it’s such an historical image that I wanted to show it here.

If you’ve been buried hip-deep in holiday preparations and celebrations, you might not have known that the Cassini Equinox Mission returned an image of Titan that shows a lake of liquid something on the surface of the cloud-shrouded moon of Saturn.  That lake is called Kraken Mare.

That little flash of light you see is a specular reflection off the surface of the liquid. Specular reflections are commonly seen on Earth when the sunlight flashes off bodies of water here. But, this is not likely to be water on Titan. Kraken is a hydrocarbon lake (hydrocarbons are things like methane and ethane). It stretches across about 400,000 square kilometers (150,000 square miles) across the northern surface.

Now, the cool thing about this image (along with the flash) is that we can actually even detect that glint. Most of the time Titan is covered in clouds.  Optically it makes it very difficult to see anything on the surface, but wavelengths of infrared light get through.  As Saturn and Titan approach their spring equinox, the viewing angle is just right, and scientists using an infrared-sensitive instrument onboard the Cassini spacecraft were able to detect the glint in infrared wavelengths.  This is pretty exciting news.  It’s cool because it’s there, first of all, and second because we’ve been able to see it with special instruments.  Third, the existence of that lake will help planetary scientists understand more about the interactions between the surface and the atmosphere of Titan and the conditions that help make the existence of that lake possible. Stay tuned!

atmosphere, atmospheric science, climate change, Earth science, NASA, terra satellite

The Ash from a Distant Mountain

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Watching the Fires from Space

The Southern California Fires as seen by NASA's Earth Observing System Terra satellite. Courtesy NASA. Click to embiggen.

Up here in the Rockies we’re seeing the effects of the Station Fire near Pasadena in a most dramatic way — ash in the air, blood-red sunsets and a red Moon. There’s so much ash floating around that our mountains in the distance look like one of those Japanese watercolor paintings with mist-shrouded hills.

But, far from being mist, this stuff is the particulate matter distributed from the fires consuming more than 100,000 acres (and growing) of brush, trees, and homes.  Overnight the historic (and very busy) Mt. Wilson Observatory was threatened by the fire, but thanks to the efforts of fire crews, the observatory is (so far) spared from the flames. (Note: the link goes to Mt. Wilson’s webcam which may or may not be operating.  For more info about Mt. Wilson itself, go here.)

I find it fascinating to look at the satellite images of this fire — or any fire in any region on our planet.  As time goes by, you’ll see more of these images, with the smoke plumes heading out and affecting other areas.  What happens in one place on our planet inevitably affects other places.  This is why NASA and other space agencies are launching mission after mission to study our home world — to understand the processes it experiences and how all the various systems of our planet are linked together.  Often, as with the fires in SoCal, understanding and studying these topics is a matter of life and death.