A soil-based ‘concrete’ could make buildings green, even on Mars


alkaline: An adjective that describes a chemical that produces hydroxide ions (OH-) in a solution. These solutions are also referred to as basic — as in the opposite of acidic — and have a pH above 7.

carbon dioxide: (or CO2) A colorless, odorless gas produced by all animals when the oxygen they inhale reacts with the carbon-rich foods that they’ve eaten. Carbon dioxide also is released when organic matter burns (including fossil fuels like oil or gas). Carbon dioxide acts as a greenhouse gas, trapping heat in Earth’s atmosphere. Plants convert carbon dioxide into oxygen during photosynthesis, the process they use to make their own food.

cellulose: A type of fiber found in plant cell walls. It is formed by chains of glucose molecules.

cement: To glue two materials together with a binder that hardens into a rigid solid, or the viscous glue used to affix the two materials. (in construction) A finely ground material used to bind sand or bits of ground rock together in concrete. Cement typically starts out as a powder. But once wet, it becomes a mudlike sludge that hardens as it dries.

chemical: A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.

chemistry: The field of science that deals with the composition, structure and properties of substances and how they interact. Scientists use this knowledge to study unfamiliar substances, to reproduce large quantities of useful substances or to design and create new and useful substances. (about compounds) Chemistry also is used as a term to refer to the recipe of a compound, the way it’s produced or some of its properties. People who work in this field are known as chemists.

civil engineer: An engineer who creates buildings, tunnels, water systems and other large projects that improve everyday life.

clay: Fine-grained particles of soil that stick together and can be molded when wet. When fired under intense heat, clay can become hard and brittle. That’s why it’s used to fashion pottery and bricks.

climate: The weather conditions that typically exist in one area, in general, or over a long period.

compound: (often used as a synonym for chemical) A compound is a substance formed when two or more chemical elements unite (bond) in fixed proportions. For example, water is a compound made of two hydrogen atoms bonded to one oxygen atom. Its chemical symbol is H2O.

concrete: (in construction) A simple, two-part building material. One part is made of sand or ground-up bits of rock. The other is made of cement, which hardens and helps bind the grains of material together.

cross-link: A connection that holds together two long molecules.

engineer: A person who uses science to solve problems. As a verb, to engineer means to design a device, material or process that will solve some problem or unmet need. (v.) To perform these tasks, or the name for a person who performs such tasks.

factor: Something that plays a role in a particular condition or event; a contributor.

fiber: Something whose shape resembles a thread or filament. (in nutrition) Components of many fibrous plant-based foods. These so-called non-digestible fibers tend to come from cellulose, lignin, and pectin — all plant constituents that resist breakdown by the body’s digestive enzymes.

fossil fuel: Any fuel — such as coal, petroleum (crude oil) or natural gas — that has developed within the Earth over millions of years from the decayed remains of bacteria, plants or animals.

fuel: Any material that will release energy during a controlled chemical or nuclear reaction. Fossil fuels (coal, natural gas and petroleum) are a common type that liberate their energy through chemical reactions that take place when heated (usually to the point of burning).

geometry: The mathematical study of shapes, especially points, lines, planes, curves and surfaces.

glue: A sticky substance that attaches one material to another.

graduate student: Someone working toward an advanced degree by taking classes and performing research. This work is done after the student has already graduated from college (usually with a four-year degree).

greenhouse gas: A gas that contributes to the greenhouse effect by absorbing heat. Carbon dioxide is one example of a greenhouse gas.

link: A connection between two people or things.

liquid: A material that flows freely but keeps a constant volume, like water or oil.

literally: A term that the phrase that it modifies is precisely true. For instance, to say: “It’s so cold that I’m literally dying,” means that this person actually expects to soon be dead, the result of getting too cold.

maker: A term used to describe people who are do-it-yourselfers, making things they want and need, rather than buying commercial versions of products (everything from fabric and beer to furniture and tools). Many makers are now turning to 3-D printers to create items when and where they’re needed.

Mars: The fourth planet from the sun, just one planet out from Earth. Like Earth, it has seasons and moisture. But its diameter is only about half as big as Earth’s.

model: A simulation of a real-world event (usually using a computer) that has been developed to predict one or more likely outcomes. Or an individual that is meant to display how something would work in or look on others.

molecule: An electrically neutral group of atoms that represents the smallest possible amount of a chemical compound. Molecules can be made of single types of atoms or of different types. For example, the oxygen in the air is made of two oxygen atoms (O2), but water is made of two hydrogen atoms and one oxygen atom (H2O).

network: A group of interconnected people or things. (v.) The act of connecting with other people who work in a given area or do similar thing (such as artists, business leaders or medical-support groups), often by going to gatherings where such people would be expected, and then chatting them up. (n. networking)

novel: Something that is clever or unusual and new, as in never seen before.

organic: (in chemistry) An adjective that indicates something is carbon-containing; also a term that relates to the basic chemicals that make up living organisms.

oxygen: A gas that makes up about 21 percent of Earth’s atmosphere. All animals and many microorganisms need oxygen to fuel their growth (and metabolism).

particle: A minute amount of something.

prospect: (n.) The vista (as in what’s in view) or the future of something (such as whether it’s going to be successful).

radiation: (in physics) One of the three major ways that energy is transferred. (The other two are conduction and convection.) In radiation, electromagnetic waves carry energy from one place to another. Unlike conduction and convection, which need material to help transfer the energy, radiation can transfer energy across empty space.

salt: A compound made by combining an acid with a base (in a reaction that also creates water). The ocean contains many different salts — collectively called “sea salt.” Common table salt is a made of sodium and chlorine.

silicate: A mineral containing silicon atoms and usually oxygen atoms. The majority of Earth’s crust is made of silicate minerals.

silicon: A nonmetal, semiconducting element used in making electronic circuits. Pure silicon exists in a shiny, dark-gray crystalline form and as a shapeless powder.

sodium: A soft, silvery metallic element that will interact explosively when added to water. It is also a basic building block of table salt (a molecule of which consists of one atom of sodium and one atom of chlorine: NaCl). It is also found in sea salt.

standards: (in research) The values or materials used as benchmarks against which other things can be compared. For instance, clocks attempt to match the official standard benchmark of time — the second, as calculated by the official atomic clock. Similarly, scientists look to identify a chemical by matching its properties against a known standard for a particular chemical. (in regulations) A limit above which something may not be used, sold or considered safe.

sustainability: (adj: sustainable) To use resources in a way that they will continue to be available in the future.

Texas: The second largest state in the United States, located along the southern border with Mexico. It is about 1,270 kilometers (790 miles) long and covers an area of 696,000 square kilometers (268,581 square miles).