Nature of Science
How is an observation different from an inference?
An observation is information directly taken in by one's senses. Inferences are evidence-based conclusions made about things that are not directly observed.
Describe the universe immediately after its formation.
Extremely hot and rapidly expanding from a singularity.
What is the equation for density?
D = m/v
What was here before the solar system?
A large mass star.
List the layers of the Earth in order from inside to the outside.
Inner core, outer core, mantle, crust, atmosphere
All scientific information is based on ___.
Evidence!
What is Hubble's Law?
The further a galaxy is, the faster it is moving away.
What is mass? How is it measured?
Mass is the amount of matter in a substances. It is measured using a scale.
How did the planets form?
The planets formed from the accretion of material in the nebula.
Layering based on density.
What is the goal of science?
Where did cosmic microwave background radiation come from?
It is the energy released when the first atoms formed (380,000 years after the big bang)
Volume is how much space an object takes up. It is measured using water displacement.
Where were all of the elements that make up the Sun, Earth, you, and everything else on Earth created?
How does the temperature and density of the layers change towards the center of the Earth?
The layers get hotter and more dense.
How is qualitative data different than quantitative data? Which is preferred by scientists?
Qualitative data is descriptions while quantitative data involves numbers (measurements). Scientists prefer quantitative data because it is less subjective.
Why is the "big bang" theory a good and bad name for the theory that explains how the universe came about?
"Big bang" tends to make people think of an explosion - this can make people think that the beginning of the universe was loud, fiery, explosion of matter, which isn't true. However, the early universe is like an explosion in that it expanded out from a single spot, much like matter in an explosion does.
How does temperature affect the density of a substance?
As temperature increases, density decreases.
How did Earth's moon form? What are two consequences of this?
Earth's moon formed from a giant collision that caused molten material to be ejected in to space. This material rotated around the Earth and eventually came together to make the moon. Other consequences of this collision were the tilting of the Earth (and therefore seasons) and a longer day-length.
How is ocean crust different from continental crust?
Ocean crust is thinner, more dense, and younger than continental crust.
How are scientific theories and scientific laws similar and different?
Laws and theories are both heavily supported by evidence, held in equally high regard, and both can be used to make predictions. Theories are explanations while laws are descriptions of patterns.
Describe how hydrogen, helium, elements up to iron, and elements larger than iron came about in our universe.
Hydrogen and some helium atoms formed shortly after the big bang when energy converted to atomic particles and these particles came together to make atoms. Helium atoms and atoms of elements up to iron formed in the core of large mass stars from nuclear fusion. Elements larger than iron formed from nuclear fusion in supernovas.
How does density determine the position of a substance in its surroundings?
If an substance is more dense than its surroundings, it will sink. If a substance is less dense than its surroundings it will float.
Describe how Earth's geosphere, hydrosphere, atmosphere, and life has changed over time.
Geosphere: molten -> crust -> changes from plate tectonics, weathering, and erosion
Hydrosphere: water in rock -> water vapor released -> vapor cools into liquid -> liquid water falls to Earth and collects in low areas
Atmosphere: hydrogen from nebula -> hydrogen blown away -> CO2, N3, H2O, CH4, NH3 from rocks -> CO2, H2O, NH3 removed while O2 from cyanobacteria added
Biosphere: no life -> very simple anaerobic life -> cyanobacteria -> aerobic life -> more complex and diverse life forms -> extinctions followed by rise of new species
What is the lithosphere and asthenosphere?
The lithosphere consists of the crust and uppermost part of the mantle. It is rigid and broken into plates. The asthenosphere is the partially melted layer of the mantle that sits beneath the lithosphere.