The environment is a term that describes all living and non-living things that make up the physical world.
Climate 101: Cause and Effect
Global warming occurs when carbon dioxide (CO2) and other air pollutants and greenhouse gases collect in the atmosphere and absorb sunlight and solar radiation that have bounced off the earth’s surface. Normally, this radiation would escape into space—but these pollutants, which can last for years to centuries in the atmosphere, trap the heat and cause the planet to get hotter. That's what's known as the greenhouse effect.
In the United States, the burning of fossil fuels to make electricity is the largest source of heat-trapping pollution, producing about two billion tons of CO2 every year. Coal-burning power plants are by far the biggest polluters. The country’s second-largest source of carbon pollution is the transportation sector, which generates about 1.7 billion tons of CO2 emissions a year.
Global warming is causing global mean sea level to rise in two ways. First, glaciers and ice sheets worldwide are melting and adding water to the ocean. Second, the volume of the ocean is expanding as the water warms. A third, much smaller contributor to sea level rise is a decline in the amount of liquid water on land—aquifers, lakes and reservoirs, rivers, soil moisture. This shift of liquid water from land to ocean is largely due to groundwater pumping.
Physics is the natural science that studies matter, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines, and its main goal is to understand how the universe behaves.
A force is a push or pull acting upon an object as a result of its interaction with another object. There are a variety of types of forces:
Air Resistance Force
Newton’s Law of Motion
Physical principles discovered over 300 years ago by Sir Isaac Newton. Newton worked in many areas of mathematics and physics. In 1686, he presented his three laws of motion in the "Principia Mathematica Philosophiae Naturalis."
The first law says that any object in motion will continue to move in the same direction and speed unless forces act on it. That means if you kick a ball it will fly forever unless some sort of forces act on it! As strange as this may sound, it's true. When you kick a ball, forces start to act on it immediately. These include resistance or friction from the air and gravity. Gravity pulls the ball down to the ground and the air resistance slows it down
The second law states that the greater the mass of an object, the more force it will take to accelerate the object. There is even an equation that says Force = mass x acceleration or F=ma. This also means that the harder you kick a ball the farther it will go. This seems kind of obvious to us, but having an equation to figure out the math and science is very helpful to scientists.
The third law states that for every action, there is an equal and opposite reaction. This means that there are always two forces that are the same. In the example where you kicked the ball there is the force of your foot on the ball, but there is also the same amount of force that the ball puts on your foot. This force is in the exact opposite direction.
Biology is the natural science that studies life and living organisms, including their physical structure, chemical processes, molecular interactions, physiological mechanisms, development and evolution.
Reproduction is the biological process by which new individual organisms – "offspring" – are produced from their "parents". Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. There are two forms of reproduction: asexual and sexual.
Genetics is the study of how genes and how traits are passed down from one generation to the next. It studies how living organisms, including people, inherit traits from their parents.
Our genes carry information that affects our health, our appearance, and even our personality!
The science that deals with the properties, composition, and structure of substances (defined as elements and compounds), the transformations they undergo, and the energy that is released or absorbed during these processes. Every substance, whether naturally occurring or artificially produced, consists of one or more of the hundred-odd species of atoms that have been identified as elements.
A process in which one or more substances, the reactants, are converted to one or more different substances, the products. Substances are either chemical elements or compounds. A chemical reaction rearranges the constituent atoms of the reactants to create different substances as products.
States of Matter
Matter makes up our planet and the whole universe. On Earth, all matter exists in one of three different states: solid, liquid and gas. A solid can hold its shape (for example, water in solid form is ice). A liquid like water forms a pool: it flows or runs but it can't be stretched or squeezed.
A gas can flow, expand and be squeezed; if it is in an unsealed container it escapes (water in gas form is steam).
Intermolecular forces are forces of attraction or repulsion that occur between neighboring particles such as molecules, atoms and ions.
Astronomy is the study of everything in the universe beyond Earth’s atmosphere. That includes objects we can see with our naked eyes, like the Sun, the Moon, the planets, and the stars . It also includes objects we can only see with telescopes or other instruments, like faraway galaxies and tiny particles.
Stars are giant spheres of superhot gas made up mostly of hydrogen and helium. Stars get so hot by burning hydrogen into helium in a process called nuclear fusion. This is what makes them so hot and bright. Our Sun is a star. The life cycle of a star spans billions of years.
A galaxy is a group of stars and planets. The stars tend to spin around a center of high gravity, sort of like the planets spin around the Sun in the Solar System. Galaxies are huge and can have trillions of stars. We live in the Milky Way galaxy! Scientists think there are over 100 billion galaxies. The universe is huge!
Black holes are one of the most mysterious and powerful forces in the universe. A black hole is where gravity has become so strong that nothing around it can escape, not even light. The mass of a black hole is so compact, or dense, that the force of gravity is too strong for even light to escape. Black holes are truly invisible. We can't actually see black holes because they don't reflect light. Scientists know they exist by observing light and objects around black holes.
Time Scale of the Cosmos
The Cosmic Calendar is a scale in which the 13.7 billion year lifetime of the universe is mapped onto a single year. This image helps to put cosmology, evolution, and written history in context. At this scale the Big Bang took place on January 1 at midnight, and the current time is mapped to December 31 at midnight. At this scale, there are 434 years per second, 1.57 million years per hour, and 37.7 million years per day. The concept was popularized by Carl Sagan in his book The Dragons of Eden and on his television series Cosmos as a way to conceptualize the vast amounts of time in the history of the universe.