redox state

Chemical reaction environment determined by the balance of negatively and positively charged atoms

replication

Reproduction from a template

ribose

Five-carbon sugar

RNA

Ribonucleic acid, a molecule involved in transcription of the instructions in DNA. Some theorize that RNA was the precursor to DNA.


single-strand break

When one strand of the DNA molecule is broken, usually by oxidative stress or certain forms of radiation

solar flare

Eruption of hot gas and radiation from the Sun’s photosphere

solar neighborhood

Sun and nearby stars

Stardust mission

NASA mission to return dust from Comet Wild 2

subduction

Geologic process by which one tectonic plate is forced under another

Sudbury

Ancient impact basin in northern Canada

supernova

Stellar explosion


tars

Complex hydrocarbons with high viscosity and melting point

tectonics

Theory that Earth’s lithosphere exists as separate and distinct plates that float on a fluid-like asthenosphere

Titan

Largest moon of Saturn

TPF

NASA’s Terrestrial Planet Finder

transition elements

Elements located in groups IB to VIIIB of the Periodic Table. They have many of the characteristics of metals.


ultraviolet

Electromagnetic radiation more energetic than visible light

UVB

Ultraviolet sunlight that penetrates the ozone layer and reaches Earth’s surface

UVC

Ultraviolet sunlight with shorter wavelength than UVB that is filtered out by Earth’s ozone layer


VPL

Virtual Planetary Laboratory, hosted by Caltech and the Jet Propulsion Laboratory

volatile

Substance with a low evaporation temperature

Vredefort

300-km impact crater in South Africa, formed about 2 billion years ago


x ray

Electromagnetic radiation more energetic than ultraviolet light



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