Astronomy 152

Astronomy

as the study of the objects that lie beyond our planet Earth and the processes by which these objects interact with one another.

The universe is a total of

Energy, Matter, Space, Time

Matter

any substance that has mass and occupies space (volume), forming everything from stars and planets to gas clouds, and is fundamentally composed of elementary particles like quarks and leptons (electrons)

Energy

fundamentally the capacity to do work or cause change

Dark Matter

Astronomers have no solid definition of “dark matter.” It has mass (hence it being matter) because it creates gravity. It does not interact with matter, light, or energy. Most abundant form of matter- shapes the structure of the universe

Potential Energy

Stored energy that is ready to do work

Kinetic Energy

When energy is doing work, typically in motion

Conserved

When energy can be converted from one form to another

Joule (J)

International Unit for Energy

Space is a backdrop

(Theory for what is the nature of space) Space could stretch out infinitely, you could venture as far out as nothingness. Allows for the idea of an infinite universe

Space is a frame

(Theory for what is the nature of space) Space is whit is between two pieces of matter. No reference points, how can you define a space between nothing and nothing. If matter is finite, then space must be finite as well

Time

What can be measured as a clock OR a progression of events from the past, through the present, and into the future

Arrow of Time or Second Law of Thermodynamics

One directional flow of time, which means time only flows in a singular direction- forward