Lecture Notes Review - Q2 Space, Climate, and Energy Topics

A comprehensive set of vocabulary flashcards covering wind energy storage, astronomy, planetary science, climate solutions, and nuclear energy topics drawn from the provided notes.

Energy storage (wind energy)

Cheap, efficient storage is needed to make wind (and solar) a viable alternative to fossil fuels by storing energy when generation exceeds demand and releasing it when generation is low.

Pumped storage (pumped hydro)

Water is pumped uphill into reservoirs when electricity is abundant and later released downhill through turbines to generate power.

Compressed air energy storage (CAES)

Extra electricity compresses air into underground caverns; later, released air drives turbines to generate electricity.

Warming/cooling problem in CAES (compression/expansion)

Compression heats the air and expansion cools it; this heat loss reduces overall energy efficiency and can affect turbine performance.

Heat management in CAES

Two approaches: (1) remove heat from compression and reuse it when expanding air; (2) capture heat with water sprays or similar methods and return it to the expanding air.

Electrolyzer

A device that uses electricity to split water into hydrogen and oxygen, storing energy chemically.

Hydrogen storage (as energy carrier)

Hydrogen produced by electrolysis stores the energy for later use in fuel cells or turbines.

Fuel cell

A device that recombines hydrogen and oxygen to produce electricity and water.

Atmospheric hindrances to ground-based telescopes

Weather, water-vapor absorption, light pollution, and turbulence (seeing) blur and degrade images.

Adaptive optics

A real-time technique using sensors and a flexible mirror to cancel atmospheric turbulence and sharpen images.

Infrared astronomy challenges

IR observations are impeded by glow from the Earth, atmosphere, and telescopes, which swamp faint signals.

Cooling of IR detectors

Detectors are cooled toward near absolute zero to reduce thermal noise.

Blocking telescope heat (IR)

Cooling/isolating the telescope and using high-dry sites or space-based platforms to minimize thermal emission.

High, dry sites or space for IR observations

Locations or environments that minimize atmospheric glow and absorption for infrared astronomy.

Radio telescope resolution

Radio wavelengths are long, giving poorer angular resolution than optical telescopes.

Interferometry (radio)

Linking multiple radio dishes to act as one large telescope, improving resolution.

Trans-Neptunian Object (TNO)

An object that orbits the Sun beyond Neptune.

Kuiper Belt

A region beyond Neptune populated by many TNOs and icy bodies.

Discovered TNOs (approx.)

About 3,900 TNOs have been discovered.

Terrestrial planet differentiation

Early melting allows heavy metals to sink and lighter rocks to rise, creating layered interiors.

Planetary differentiation

The process by which a planet becomes internally layered (core, mantle, crust) due to melting and density sorting.

Geologic activity and planet size

Larger terrestrial planets stay hot longer and remain geologically active; smaller ones cool and quiet down sooner.

Crater counting for surface ages

Dating surfaces by counting impact craters; more craters imply an older surface.

Radiometric dating basics (half-life, parent/daughter)

Dating rocks by measuring the decay of parent isotopes to daughter products with known half-lives.

Giant collision hypothesis (planet spins/tilts)

Early violent impacts reoriented spins and tilts of planets, explaining unusual rotations and obliquities.

Iron meteorites (discovery bias)

Iron meteorites are easier to recognize and resist weathering, so they are disproportionately represented among finds.

Iron vs. stony meteorites

Iron meteorites survive and stand out, biasing the observed meteorite population.

Delivery of water/organics to early Earth

Icy planetesimals and comets from beyond the snow line delivered water and organic material; giant planets helped scatter them inward.

Carbonaceous chondrites (far from Sun)

Chondrites rich in carbon, water, and organics; believed to form far from the Sun where ices could survive.

Chondrites and solar system history

Chondrites preserve original solar system material and thus inform planetary formation studies.

Early solar system resembles TTauri disks

Dusty, planet-forming disks around young stars (TTauri) resemble our early solar system’s protoplanetary disk.

OSIRIS-REx target: Bennu

Bennu is carbon-rich, near-Earth, and accessible for sample collection and return.

Yarkovsky effect

Small, gradual change in an asteroid’s orbit due to uneven heating and re-emission of absorbed solar energy.

ALH 84001 (Martian meteorite)

Meteorite from Mars that carries gases similar to Mars’ atmosphere, indicating Martian origin.

Ruth Gates coral adaptation

Breeding and cultivating heat-tolerant corals to help reefs survive warmer oceans.

Perovskites (solar cells)

A new class of solar cell material that can be cheaper and more easily manufactured than silicon while absorbing light efficiently.

Lisa Dyson and carbon capture economy

Concept of turning captured CO2 into useful products to make carbon capture financially viable.

Soil carbon sequestration (Dave Legvold)

Practices that store carbon in soils, reducing atmospheric CO2.

Direct air capture (DAC) economics

Removing CO2 directly from ambient air; storage or conversion to products; currently costly and energy-intensive.

Synthetic fuels from captured CO2

Using captured CO2 and hydrogen to create fuels (e.g., jet fuel) to replace fossil fuels.

Geoengineering drawbacks

Potential to disrupt climate/weather and does not address ocean acidification caused by CO2.

Forests and mangroves in carbon capture

Mapping and protecting forests and mangroves to maximize natural carbon sequestration.

Nuclear power carbon footprint (median)

Nuclear power's median carbon footprint is lower than fossil fuels and comparable to solar/wind; manufacturing can raise estimates.

Benefits of nuclear power

Provides steady power, emits very little CO2, and reduces reliance on fossil fuels.

Drawbacks of nuclear power

Waste disposal challenges, high costs, and risk of accidents.

How solar cells generate electricity

Sunlight excites electrons in the cell, generating an electric current; few moving parts contribute to longevity.

Challenges for widespread solar adoption

High manufacturing costs and intermittency due to variable sunlight.

Dust coagulation in planet formation

Dust grains stick together via static electricity and gravity, enabling growth into larger bodies.

Primary atmospheres of planets

Terrestrial planets tend to lose their primary atmospheres after formation, while gas giants retain them.

Loss of terrestrial primary atmospheres

Small planets lose light gases due to heat and solar wind stripping.

Pluto atmosphere discovery (occultation)

Starlight dimming during a occultation revealed Pluto’s atmosphere.

Alice instrument (New Horizons)

Spectrograph onboard New Horizons that analyzes light passing through Pluto’s atmosphere to identify gases.

Pluto’s small size explanation

Neptune’s gravity scattered material and truncated Pluto’s growth, keeping it small.

Hubble ring discovery near Pluto (2008)

Hubble observed faint rings and debris in Pluto’s vicinity.

Power plants: basic electricity generation

Burn fuel to make steam, spin turbines, and generate electricity.

Renewable energy costs trend

Costs for wind/solar have fallen with technology; fossil fuel costs rise due to resource limits and pollution costs.

Subsidies (definition)

Government payments that lower fossil fuel prices, influencing market competitiveness.

Future costs of pollution

Costs associated with pollution may be borne by future generations, even if they do not consume today’s energy.

Uranium enrichment

Enriching U-235 to increase its proportion for nuclear fuel or weapons.

Nuclear waste disposal issues

Long-lived, dangerous waste requiring secure, long-term storage; political and logistical challenges.

Nuclear fusion vs fission

Fusion requires extreme heat/pressure to overcome repulsion; fission splits heavy nuclei to release energy.

Q-value (nuclear fusion)

Net energy gain of a nuclear reaction; energy output minus energy input must be positive.

Radiometric dating example (half-life)

Dating rocks by measuring decay products and using half-life to infer age.

Nebula-to-disk transition (rotation/angular momentum)

Rotation causes a collapsing cloud to flatten into a protoplanetary disk rather than staying spherical.

Condensation near protosun

Rock and metal condense closer to the Sun, while ices condense farther out.

Gas giants and hydrogen/helium capture

Massive, cold outer planets can retain light gases that terrestrial planets cannot.

Planetary atmosphere sources and sinks

Volcanism and comets supply atmospheres (sources); plants and oceans remove gases (sinks).

Carbon cycle in Earth's atmosphere

Sources: volcanism, burning fossil fuels; Sinks: photosynthesis, oceanic absorption.

Why Earth retains CO2 but not H2

CO2 is heavier and less prone to escape; hydrogen is light and escapes more readily due to higher thermal speeds.

Mean molecular speed and atmospheric escape

lighter gases move faster on average, making them more likely to escape a planet’s gravity.