Question

Each of the following gives a statement that a future explorer might someday make. In each case, decide whether the claim seems plausible in light of current knowledge. Explain clearly; because not all of these have definitive answers, your explanation is more important than your chosen answer. On the smallest moon of Uranus, my team discovered a vast, subsurface ocean of liquid water.

Short answer

A subsurface ocean on a Uranus moon is speculative but plausible given icy surfaces and internal heating possibilities.

Step-by-step solution

Evaluate Current Knowledge on Uranus's Moons

First, consider what is currently known about Uranus's moons, particularly the smaller ones. Uranus has 27 known moons with Titania being the largest. The smaller moons, like Miranda, are less studied. Past studies have suggested icy surfaces, but there's limited data on subsurface features due to the lack of close exploration missions.

Consider Subsurface Oceans Possibility

Recent planetary science suggests that subsurface oceans might exist on icy bodies, such as moons, due to tidal heating or radioactive decay that could maintain liquid water beneath the surface. Observations from other celestial bodies, like Europa and Enceladus, have shown that subsurface oceans are plausible under certain conditions.

Analyze Feasibility of Liquid Water

Evaluate the necessary conditions for an ocean - a heat source, sufficient ice melting, and containment under a solid crust. Uranus's distance from the sun implies it's cold, but internal heat may provide the necessary conditions, as seen in moons of Jupiter and Saturn. The plausibility increases with detected geological activity or anomalous magnetic fields which haven't been substantially observed for Uranus's moons yet.

Draw a Conclusion on Plausibility

Based on current scientific understanding, while it's speculative, it isn't impossible to have a subsurface ocean on one of Uranus's ice-covered moons. The presence of certain conditions that could allow for such oceans has been hinted at in other distant solar system bodies.

Key concepts

Subsurface Oceans

Subsurface oceans are bodies of liquid water that exist beneath the surface of a planet or moon. They are hidden from direct observation but are considered possible in many icy moon scenarios. Scientists have hypothesized about these oceans based on two main factors: heat and pressure. Even in extremely cold environments, such as those found on moons far from the sun, subsurface oceans might form if there's a sufficient heat source. This heat can come from the moon's interior and helps warm the ice above to create water. Pressure from the overlying ice can also keep water in a liquid state, despite low temperatures.

We have compelling evidence of subsurface oceans in moons like Jupiter's Europa and Saturn's Enceladus. These moons are thought to have enough heat and pressure conditions to maintain vast amounts of liquid water beneath their icy crusts. Similarly, the theory extends to less explored moons of Uranus, suggesting that, while direct evidence is scarce, the conditions under which subsurface oceans can occur are not unique to moons of Jupiter and Saturn.

Planetary Science

Planetary science is the study of planets, moons, and planetary systems regarding their formation, evolution, and potential for life. This field involves understanding geological activity, atmospheres, and possible water reservoirs in various celestial bodies. When scientists explore moons and planets, they rely on a combination of observational data, satellite imagery, and spacecraft missions to gather evidence.

In the case of Uranus's moons, our understanding is still developing. Although fewer studies have focused on them compared to bodies closer to the sun, the interest in these distant moons is growing. The potential for finding liquid water subsurface oceans makes these moons intriguing targets for future exploration missions. By studying them, scientists hope to gain further insights into the processes and conditions that could allow liquid water and possibly life to exist in seemingly harsh environments.

Icy Moons

Icy moons are natural satellites that have surface compositions predominantly made of ice. The surfaces of these moons are often covered by thick ice crusts, beneath which subsurface oceans might exist. Icy moons are found throughout the solar system, with some of the most well-known examples being Europa, Ganymede, and Enceladus.

These moons are not uniformly explored due to their distance and the challenges involved in sending spacecraft to the outer solar system. However, the icy crusts bear clues to their history and potential internal activity. Dark streaks, geysers, and surface cracks all offer hints of subsurface movement, possibly driven by the heat from radioactive decay or tidal forces. Uranus's icy moons, although less researched, may very well share these features, making them significant for comparative studies and understanding the conditions that home isolated pockets of liquid water.

Tidal Heating

Tidal heating is a process where gravitational interactions cause a celestial body to experience internal heating. This occurs when a moon's orbit is slightly elliptical, leading to varying gravitational pulls at different points in the orbit. These variations create internal friction, generating heat.

On moons distant from the sun, such as those orbiting Uranus, tidal heating can be crucial for maintaining subsurface oceans. It compensates for the lack of solar heat, providing necessary energy to keep water beneath thick ice layers in a liquid state. Observations of active geysers and volcanic-like activities on other moons are often attributed to tidal heating. Although currently speculative for Uranus's moons, the presence of this process could dramatically alter our understanding of their geology and potential habitability. Future missions might reveal more about the role of tidal forces in shaping these distant icy bodies.