Titan, A Place To Stretch Your Wings And Fly

Saturn’s largest moon Titan slowly covers smaller Tethys with its prominent Odysseus Crater in Nov. 2009. Credit: NASA/JPL-Caltech/Space Science Institute

Feeling hemmed in by winter? Held back by cold? Time to consider a Web vacation to Saturn’s largest moon Titan. One thing’s for sure, the place has a lot of atmosphere. Thickly cloaked in a blanket of air composed of 98% nitrogen, Titan’s atmosphere is so dense (1.45 times that of Earth) and gravity so weak, that humans could fly by donning a pair of homemade wings and flapping like a bird. Since many of us have dreamed of flying on our own power, who would have guessed Titan would be the closest outpost to offer that opportunity.

In this photo taken in near-infrared light, we see Saturn’s ring plane cutting across the foreground. Dark land features are visible on Titan’s surface beneath this haze. Credit: NASA/JPL-Caltech/Space Science Institute

Titan spans 3,200 miles (5,150 km) across or almost exactly 1 1/2 times the size of the moon. Besides nitrogen, the atmosphere also contains 1.4% methane and a smattering of hydrocarbons like ethane and propane. Ultraviolet light from the sun cooks these into an orange, smoggy moon-wide haze; to image the surface requires infrared cameras and telescopes that can “see” in haze-busting infrared light.

Low winter sunlight catches the edge of Titan’s south polar vortex in this photo taken by the Cassini space probe in July and recently released by NASA. Click for a closeup color photo. Credit: NASA/JPL-Caltech/Space Science Institute

Today it’s summer in the orange moon’s northern hemisphere and winter in the south. During Cassini’s long stay at Saturn (since 2004), it’s seen seasonal changes on Titan. When it first arrived, a hood of high clouds named the north polar vortex, swirled above the north pole. A similar hood – the south polar vortex – recently formed over the south polar region. Scientists believe it’s related to the beginning of southern winter.

Watch the south polar vortex spin in this animation compiled of Cassini photos. Credit: NASA/JPL-Caltech/Space Science Institute

The vortex spins around once every 9 hours hours, some 42 times faster than Titan’s 16-day rotation period, floats above the regular cloud deck, high enough for its curving edge to catch the last of the sun’s rays. A beautiful sight!

According to NASA, scientists think these new images show open cell convection – air sinks in the center of the cell and rises at the edge, forming clouds at cell edges. No one knows exactly what creates the vortex,but it does appear to be a seasonal feature.

Besides a thick atmosphere, methane clouds and hydrocarbon haze, Titan dazzles with thousands of lakes filled with liquid natural gas – ethane and methane – that range in size from pond-size to larger than Lake Superior. Only Titan’s extremely cold surface temperature of -290 F (-179 C) and substantial atmospheric pressure can turn what are normally gases on Earth into liquids and keep them that way.

Clouds cross the sky above lakes filled with ethane and methane near Titan’s north pole in this image/diagram made by Cassini. The Kraken Sea is as large as Europe’s Caspian Sea. Credit: NASA

A most fascinating world where humans might one day fly of their accord and even ply boats across hydrocarbon lakes beneath a peach-colored sky.


19 Responses

  1. Dominik

    Good evening Bob, ( well at least in Europe now )

    interesting topic, but might be some time till humans actually are able to travel to Titan. Especially with those “ancient” chemical rockets.

    Topic change… the Geminids peak on Saturday morning this weekend, don’t they?
    I intend to stay awake and watch them when the moon has set, so some time after 5am.
    I’m trying to display the Geminid meteor shower in Stellarium. ( By the way thanks for introducing us/me to Stellarium, it’s really fantastic. )
    How can I do that?
    It’s displaying meteors, but I think they resemble the Leonids because that is the constellation where they radiate from.

    1. astrobob

      Hi Dominik,
      Yes, I plan to watch the Geminids too. Will very soon have a little write up on it. I don’t think Stellarium can show individual meteor showers – not that I’m aware of. I plot the radiant and then create my own in Stellarium using Photoshop.

          1. Dominik

            Thanks a lot, had rather cloudy skies for at least the last 2 weeks.
            No clouds today, might continue till Friday/Saturday.
            I hope you’ll have clear skies aswell!

  2. Edward M. Boll

    If we fly up there we will have to have lightweight clothes and a lot of them in that frigid envirement, plus lightweight oxygen tanks to keep us up, if that were possible.

      1. Giorgio Rizzarelli

        I though the same thing. But when we’ll have technology to take humans there maybe we’ll have thin spacesuits composed of some new material (again fantasies)

  3. Robert

    Thank you for the web vacation awesome topic I have been fascinated with Titan ever since I saw the first pictures of it from voyager when I was a much younger man. The pictures now a days are amazing so much detail really cool I could get lost for hours looking at pics and reading articles about Titan on the Internet. On another topic comet Lovejoy is it heading toward the sun right now? What is going on I have not seen any orbit tracks but I have seen the comet with binoculars about a month ago.

    1. astrobob

      Hi Robert,
      Glad you enjoyed your “vacation”. Lovejoy is about mag. 5.5-6. I just saw with the naked eye late last week. It will be around in the morning sky for months to come fading all the while.

  4. Hello Mr. Bob! I Stumbled upon your blog thanks to my teacher. I really enjoyed reading about one of Saturn’s Moons, because it’s such a contrast from our own Moon, or one of Jupiter’s moons. Don’t get me wrong they’re interesting but I like variety when it comes to moons, so reading this post! Thank you!

    1. astrobob

      Hi Jamie,
      Glad you stumbled by. Titan’s one of the coolest moons because of its atmosphere. It’s also the only other place in the solar system that has liquid on its surface.

  5. Norman Sanker

    Hey Bob,

    In Arthur C. Clark’s “Childhood’s End,” it was theorized that the Overlords came from a planet with a thick atmosphere and low gravity. That seemed absurd to me at the time–guess not. Later.

    Norman Sanker

  6. Edward M. Boll

    I was going to lok for Lovejoy this morning. Normally, I can hold my binoculars and focus them at the same time, but a fall on the ice Friday morning has had me unable to lift my left hand high enough to do that while focusing on the stars. I have been reluctant, but I guess I need a chiropractor.

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