Related Experiment Video
Updated: May 1, 2026
09:17
Experimental Investigation of the Flow Structure over a Delta Wing Via Flow Visualization Methods
Published on: April 23, 2018
10.2K
The lakes of Titan
E R Stofan1, C Elachi, J I Lunine
1Proxemy Research, Rectortown, Virginia 20140, USA. estofan@proxemy.com
Nature
|January 5, 2007
Summary
Scientists found definitive evidence of lakes on Saturn's moon Titan. Radar imaging revealed over 75 dark patches, indicating liquid methane and ethane bodies, supporting an active hydrological cycle.
Area of Science:
- Planetary Science
- Astrobiology
- Geology
Background:
- Titan, Saturn's largest moon, has long been theorized to host surface liquids.
- Previous missions found evidence of flowing liquids but lacked definitive proof of stable bodies like lakes or oceans.
Purpose of the Study:
- To provide definitive evidence for the presence of surface lakes on Titan.
- To investigate the state and characteristics of these liquid bodies.
Main Methods:
- Analysis of high-resolution radar imaging data from the Cassini spacecraft's T16 flyby on July 22, 2006.
- Interpretation of radar-dark patches (≥70°N latitude) based on reflectivity and morphology.
Main Results:
- Discovery of over 75 circular to irregular radar-dark patches in Titan's northern hemisphere.
- Identification of features consistent with lakes, including channels and depressions.
- Observation of lakes in various states, from liquid-filled to partly dry, within topographic depressions.
Conclusions:
- The findings provide the strongest evidence to date for surface lakes on Titan.
- These lakes support the existence of an active, condensable-liquid hydrological cycle on Titan.
- The lakes are likely replenished by rainfall and/or interaction with subsurface liquid methane reservoirs.
More Related Videos
Related Concept Videos
01:23States of Water
46.5K
Water exists in any one of the three classical states: solid (ice), liquid (water), and gas (steam or water vapor). The state of water depends on i) the intermolecular forces that draw molecules together and ii) the kinetic energy that leads to movements that pull them apart.
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
Water freezes when the intermolecular forces are greater than the kinetic energy. Unlike most other substances, water is less dense in its solid state than in its liquid state. This is because each water molecule can form...
46.5K
01:16Kendall's Tau Test
1.1K
Kendall's tau test, also known as the Kendall rank coefficient test, is a nonparametric method for assessing association between two variables. This test is particularly useful for identifying significant correlations when the distributions of the sample and population are unknown. Developed in 1938 by the British statistician Sir Maurice George Kendall, the tau coefficient (denoted as τ) serves as a rank correlation coefficient, with values ranging from -1 to +1.
A τ value of +1...
A τ value of +1...
1.1K
01:20Region of Convergence of Laplace Tarnsform
1.4K
The Region of Convergence (ROC) is a fundamental concept in signal processing and system analysis, particularly associated with the Laplace transform. The ROC represents an area in the complex plane where the Laplace transform of a given signal converges, determining the transform's applicability and utility.
Consider a decaying exponential signal that begins at a specific time. When deriving its Laplace transform, the time-domain variable is replaced with a complex variable. This...
Consider a decaying exponential signal that begins at a specific time. When deriving its Laplace transform, the time-domain variable is replaced with a complex variable. This...
1.4K
01:17Turbine-Governor Control
1.3K
Turbine-governor control is crucial for maintaining power system stability by balancing turbine mechanical power output with electrical load demand. This mechanism ensures that generator frequency and rotor speed are within acceptable limits during load variations. Turbine-generator units store kinetic energy due to their rotating masses; this energy is released to meet the load requirement when the load increases. The electrical torque of turbines rises to meet the demand, whereas the...
1.3K
01:19Quality of Water
757
In concrete preparation, the quality of water is paramount as it affects the strength and durability of the concrete. Potable water is usually preferred; however, it must not have excessive sodium or potassium to prevent compromising the concrete's integrity. Water quality is typically evaluated based on impurities such as dissolved solids, chlorides, and sulfates, and its pH value is ideally between 6 and 8. Even slightly acidic natural water may be acceptable unless it contains harmful...
757
01:26Transient Ischemic Attack l: Introduction
18
A transient ischemic attack (TIA) is a brief episode of neurological dysfunction caused by a temporary, focal reduction in cerebral blood flow. Although symptoms resemble those of an ischemic stroke, the interruption in perfusion is short-lived and does not cause permanent infarction. TIAs are clinically important because they often serve as early warning events for future stroke.Mechanisms of Transient Cerebral IschemiaTransient cerebral ischemia may arise through several mechanisms. One...
18