Lakes of Titan - History - Observation of Specular Reflections

Observation of Specular Reflections

On 21 December 2008, Cassini passed directly over Ontario Lacus at an altitude of 1900 km and was able to observe specular reflection in radar observations. The signals were much stronger than anticipated and saturated the probe's receiver. The conclusion drawn from the strength of the reflection was that the lake level did not vary by more than 3 mm over a first Fresnel zone reflecting area only 100 m wide (smoother than any natural dry surface on Earth). From this it was surmised that surface winds in the area are minimal at that season and/or the lake fluid is more viscous than expected.

On 8 July 2009, Cassini's Visual and Infrared Mapping Spectrometer (VIMS) observed a specular reflection in 5 micron infrared light off a northern hemisphere body of liquid at 71° N, 337° W. This has been described as at the southern shoreline of Kraken Mare, but on a combined radar-VIMS image the location is shown as a separate lake (later named Jingpo Lacus). The observation was made shortly after the north polar region emerged from 15 years of winter darkness. Because of the polar location of the reflecting liquid body, the observation required a phase angle close to 180°.

Read more about this topic:  Lakes Of Titan, History

Famous quotes containing the words observation of, reflections and/or observation:

    It is a great pity—but ‘tis certain from every day’s observation of man, that he may be set on fire like a candle, at either end—provided there is a sufficient wick standing out.
    Laurence Sterne (1713–1768)

    From the oyster to the eagle, from the swine to the tiger, all animals are to be found in men and each of them exists in some man, sometimes several at the time. Animals are nothing but the portrayal of our virtues and vices made manifest to our eyes, the visible reflections of our souls. God displays them to us to give us food for thought.
    Victor Hugo (1802–1885)

    Morality without religion is only a kind of dead reckoning—an endeavor to find our place on a cloudy sea by measuring the distance we have run, but without any observation of the heavenly bodies.
    Henry Wadsworth Longfellow (1807–1882)