cosmology Flashcards
(31 cards)
if a galaxy is moving away at a higher velocity what does that suggest about its distance from earth
they were created in stars through nuclear fusion- released during
how does the expansion of the universe affect the wave lengths of light over time
as the universe expands, light waves are stretched, increasing wavelength (redshift)
what’s blueshift? why is it less common than redshift?
blueshift occurs when object is moving toward us- rare because most galaxy’s move away due to expansion of the universe
what is the doppler effect?
describes how waves change frequency based on motion
what does redshift indicate about a celestial object motion?
it’s moving away from us
what does hubbles law state about the movement of galaxies?
the farther away the galaxy: the faster its receding from us
how does redshift support the idea of an expanding universe?
redshift shows galaxies are moving away from us and therefore expanding
what discovery provided evidence that the universe is expanding?
the redshift of galaxies, edwin hubble
what is cosmic background microwave radiation and why is it important?
the faint glow of radiation leftover from the early universe
which is not considered evidence for big bang?
the presence of black holes
which fundamental forces emerges shortly after the big bang?
gravity, strong nuclear force, weak nuclear force, electromagnetism
what does the big bang theory suggest happens at t=0
universe began as a small hot dense singularity
who first proposed the big bang theory?
georges lemaitre
why is the steady state model no longer supported?
inconsistent with observational evidence (eg. cosmic microwave background radiation)
which theory suggests the universe has always existed in roughly the same form
steady state model
why is repeatability important in an experiment?
ensures results are reliable and not due to chance
what does r2 value in an scatterplot mean?
correlation strength between independent and dependent variables
five steps to scientific method
-destruction
-design
-data collection
-data analysis
-conclusion
radioactive hazard?
exposure to ionizing radiation
biohazard?
biological dangers (bacteria, viruses)
supernovae?
scatters heavy elements into space which condense into stars and planetary systems
high mass star=
black hole
medium mass star=
neutron star
low mass star=?
white dwarf
