Astronomy Chapter 1 Review – Flashcards

Unlock all answers in this set

Unlock answers
question
Henrietta Swan Leavitt
answer
-discovered that the period of the bright- to-dim-to-bright cycle was related to a star's true brightness (absolute magnitude)
question
Fred Hoyle
answer
-Rejected "Big BAng Theory" - Proposed that stars make elements heavier than helium in their cores and when they explode as supernovae.
question
George Smoot and John Mather
answer
-Studied the CMBR -determined that the CMBR was anisotropic -awarded the Noble Prize in 1996
question
Vesto Slipher
answer
first person to measure redshifts from "spiral nebula" which are now known to be galaxies
question
George Lamaitre
answer
Proposed that the Universe started from a small "primeval atom" state that began expanding.
question
George Gamow
answer
studied how Big Bang reactions produced current levels of hydrogen and helium (75%H , 25%He by mass) ; after glow of the BB should fill the Universe with radiation of 5K (microwave)
question
Arno Penzias and Robert Wilson
answer
Accidentally discovered cosmic background radiation -they were studying radio signals when they came across an annoying sound in their satellite that they couldn't figure out
question
Albert Einstein
answer
created the theory of relativity and created the formula E=mc^2
question
Edwin Hubble
answer
relating galaxy speed and distance; implies universe is expanding
question
Robert Dicke
answer
Priceton professor looking to find background cosmic radiation but didnt build his radio detector in time because Penzias and Wison came across it first (CMBR)
question
Quark
answer
particle comes in six "flavors": up, down, bottom, charm, and strange. Combine to form particles called HADRONS, some of which are the components of atomic nuclei.
question
Neutrino
answer
Particles are electrically neutral and have a very small rest mass. they are created in decay of nuclei and by nuclear fusion reactions (like inside our sun)
question
Proton
answer
A positively charged particle that is a fundamental component of all atomic nuclei. The # of these in the nucleus determines the element.
question
Neutron
answer
This particle has no electric charge and exists in the nuclei of atoms.
question
Photon
answer
This particle has no rest mass and moves at the speed of light in a vacuum. Electrons can release these types of particles when they change energy states within atoms
question
Electron
answer
This particle is in the family of leptons, elementary subatomic particles. It has a negative electric charge. They play a role in such phenomena as electricity, magnetism, and thermal conductivity
question
-Has enough mass that gravity has shaped it to be round or nearly round -cleared its orbit of debris -orbits the sun
answer
planet
question
True/ False : having a moon is a requirement for something to be a planet?
answer
False: mercury and Venus have no moons
question
Weak Force
answer
It regulates radioactive decay of atomic nuclei playing a huge role in nuclear fission.
question
An attractive force between particles or bodies resulting from their mass. It is the weakest force but it is considered to occur at all distances.
answer
Gravity
question
Strong Force
answer
It binds quarks together to make subatomic particles like protons and neutrons as well as holds protons together in atomic nuclei.
question
It is a force between electrically charged particles, and is responsible for binding electrons to atomic nuclei.
answer
electromagnetic
question
Meteorite found in Antarctica. It was determined to be a rock from Mars that landed on Earth after an impact on Mars ejected it off of the Martian surface.
answer
ALH84001
question
How does ALH84001 relate to the concept of panspermia?
answer
Relates to the idea of panspermia in the way that it shows that meteorites from other worlds have landed on Earth's surface. Meteorites and comets may be able to carry forms of life on them. It is possible that life spreads through solar systems and galaxies by these types of impacts. This means that life may not have started originally on Earth, and that it's possible to have come to our planet via meteorites.
question
Panspermia
answer
the theory that life originated in outer space and was transferred to earth via asteroids or comets
question
What does light years measure
answer
distance not time
question
light year
answer
unit of distance that light travels in a year
question
about how many miles is a light year?
answer
6 trillion
question
the idea that there are no special observers or privileged places in our Universe; This is due to the fact that galaxies are not rushing through space, but are embedded in space and space itself is stretching/expanding. This means that there is no special center to the Universe.
answer
Copernican Principal
question
copernican principal analogy
answer
when cooking a loaf of raisin bread the dough represents space and the raisins the galaxies. As the dough cooks, the distances between every raisin increases. If we pick one raisin to be where we are in the Universe we see raisins moving away as the dough expands. It turns out every raisin sees the same thing!
question
Oort Cloud
answer
spherical region or shell of icy bodies that encases our entire solar system -We think that some (long period) comets originate from this region.
question
Nebula
answer
cloud of dust, hydrogen, helium and other gases that exist between stars in galaxies.
question
Meridian
answer
Line from North/ South; represents highest point object is going to get in the sky
question
Cosmic Address
answer
Earth Solar System Orion Spur (arm) Milky way Local Group Local Virgo Supercluster Laniakea Supercluster Universe
question
Age of the Universe
answer
13.8 Billion years
question
Rank distances from Smallest to Largest - Thickness of the disk of the Milky Way - Semi-major axis of Pluto's orbit -Distance to center of Milky Way - Distance to nearest star (other than our Sun), Promixa Centauri (4.2 light years)
answer
1.) Semi- major axis of Pluto's orbit 2.) distance to nearest star ( other than our sun) 3.) Thickness of the disk of the Milky way 4.) Distance to center of milky way
question
Laniakea Supercluster
answer
Defined as all of the clusters of galaxies that are moving toward a common area in the Universe call the Great Attractor. Superclusters of galaxies that are not moving toward the Great Attractor are considered to be of another system of superclusters.
question
Rank sizes from smallest to largest: A. 1 AU B. Average distance from Sun to Neptune C. Distance to center of Milky Way from our Solar System D. The Sun's diameter E. Average distance from Earth to Sun F. One light year G. Distance to Andromeda Galaxy from our Solar System
answer
1.) Sun's Diameter 2.) 1 AU 3.)Average distance from Earth to Sun 4.) Average distance from sun to neptune 5.) One Light year 6.) Distance to center of Milky way from out solar system 7.) Distance to Andromeda Galaxy from our solar system
question
An astronomy student makes the following statement,"The closest star to our galaxy is Proxima Centauri, which is about 4.2 light years away from us." Did this student use the term "galaxy" in the correct way? Explain why or why not.
answer
Our galaxy is the Milky Way and it contains our Sun and about 100-200 billion or so stars in it. Our solar system consist of our Sun and the planets (and other stuff like comets, asteroids, moons, etc). This person really means that the closest star to our solar system is Proxima Centauri which is about 4.2 light years away.
question
about how many stars are in our galaxy the milky way?
answer
100-200 billion
question
what does our solar system consist of?
answer
our sund and the planets (and comets, asteroids, moons)
question
what is proxima centauri?
answer
closest star to our solar system
question
how far away is Proxima Centauri from our solar system?
answer
4.2 light years away - nearest star to us other than sun
question
Shape of Milky Way Galaxy
answer
Barred spiral with warping
question
Galactic year
answer
time it takes our solar system to orbit the milky way
question
how long is a galactic year?
answer
240 million years
question
Sag A*
answer
site of the super massive black hole in the center of the milky way (look at picture)
question
whats the best way to try to communicate with other civilzations in our galaxy?
answer
Radio waves
question
are radio waves light waves?
answer
yes
question
how fast and where to radio waves travel
answer
speed of light and in vacuum -can also travel through thick regions of dust and gas -only form of light that can travel through all of the disk bc most plantes in galasy are probably in the spiral arms
question
true/false: x-rays are a good choice to communicate to aliens with
answer
false: they are easily stopped by earth's atmosphere
question
Golden Record
answer
record sent on the voyager spacecraft launched in 1977 -contains sounds and images -115 images -many natural sounds -see notebook for what the symbols mean
question
why was tyson unhappy with the opening scene in the movie contact
answer
it was really in accurate because the movie showed the radio waves moving past planets and it was playing sounds such as music and mlk jrs speech passing by, but radio waves move at the speed of light so the sounds should have been playing much further past the planets.
question
why is tyson so upset about hollywood aliens?
answer
they look too human like -snake on earth is more "alien" looking than hollywood's
question
The lovely creature below is a Pompeii worm. It lives at hydrothermal vents deep in the Pacific Ocean at scalding temperatures of 176 degrees F. What do scientists call organisms like the Pompeii worm that like very hot, very cold, very alkaline, etc. environments?
answer
Extremophiles
question
Emission Spectra
answer
a gas is energized to move electrons between orbitals), can be used to identify elements/chemicals in far away stars/gas clouds, etc. Every element has unique emission spectra like a fingerprint. - goes from dark purple colors on the left to blue to green to orange to red on the right
question
spectrum with energy levels appearing to be moving up is
answer
absorption
question
When an electron moves down (ex: n=5 to n=2) what happens?
answer
photon is released
question
what is it called when an electron releases a photon?
answer
emission
question
Transitions moving down on the graph and emitting what color is it shifting?
answer
red
question
transitions moving up absorb more what color
answer
violet
question
doppler shift
answer
shift in wavelength of light or sound that depends on the relative motion of the source and the observers
question
Red Shift
answer
-Longer Wavelength -less frequency -away from observer
question
Blue Shift
answer
-shorter wavelength -higher frequency -toward the observer
question
Emission
answer
Electron releases a photon -falls to lower energy level in atom -causes presence of light -High-low=lose energy (light released)
question
Absorption
answer
electron takes in a photon -jumps to higher energy level in atom -causes absence of light -low -high= takes energy
question
Alania qua
answer
supercluster that we live in
question
spiderweb look is?
answer
superclusters
question
give that holds galaxy
answer
dark matter
question
is theblack hole in our galaxy active?
answer
no
question
the farther away the galaxy, the faster its motion away is
answer
hubbles laws
question
the "time" in hubbles law stands for what?
answer
how long the universe has been expanding, aka the age of the universe. -slope= 1/age of the universe
question
Absolute magnitude (M)
answer
the actual magnitude of a star that is beyond earth pespective
question
apparent magnitude (m)
answer
the magnitude of a star in earth's view
question
Lower magnitudes have a dimmer or brighter appearance?
answer
Bright -LOWER THE BRIGHTER
question
what unit does the formula (m-M)=5log(d)-5 give you answers in?
answer
parsecs; must convert to light years
question
Period in which electrons attach to nuclei; photons now travel freely; CMBR forms
answer
Recombination
question
Period from 10-6 to 1 second; it is now cool enough for quarks to make protons and neutrons as well as their anti-particles
answer
hadron epoch
question
In this period, W, Z, and Higgs bosons are created through particle interactions; the Higgs field endows particles with mass; at the end the electroweak force splits into the electromagnetic and the weak forces
answer
electroweak epoch
question
Period from 10-36 s to 10-32 s; GUT force splits into the strong and electroweak forces; triggers a rapid expansion of space; at the end of this time the universe is now the size of a grapefruit
answer
inflation
question
Period from 0 to 10-43 s; temperature is about 1032 K; one unified "superforce;" must have had energy fluctuations from point to point
answer
Planck Epoch
question
which epoch is inflation the first part of?
answer
electroweak epoch
question
In this period, the temperature is about 1 billion K; protons and neutrons begin to fuse to make nuclei such as H, He, and Li
answer
Nucleosynthesis
question
In this period the temperature of the universe falls below 4 K; matter density falls and the expansion of the Universe begins to accelerate
answer
dark energy domination
question
This period lasts from the release of the CMBR up to the formation of the first stars
answer
Dark Ages
question
In this period, galaxies form and change in the areas where large concentrations of dark matter exists
answer
galaxy formation and evolution
question
In the period, all of the 4 fundamental forces exist; quarks along with their anti-particles exist in a plasma state or "soup;" matter and anti-matter meet and annihilate; matter particles slightly outnumber the anti-matter particles 1,000,000,001 to 1,000,000,000
answer
Quark Epoch
question
In the period from 1s to 3 minutes, leptons and anti-lepton pairs are created in equilibrium; leptons dominate the mass of the Universe
answer
Lepton Epoch
question
In the period from 150 million to 1 billion years, the first quasars form and the radiation from them reionizes the plasma in the Universe
answer
Reionization
question
. In this period, which may have occurred as early as 150 million years after the Bang, stars begin to form in collapsing gas clouds
answer
Stelliferous Era
question
In the period from 3 minutes to 240,000 years the Universe is filled with hot, dense opaque soup of nuclei, free electrons, and photons; photons dominate the energy of the Universe
answer
Photon Epoch
question
In the period, gravity separates from the "superforce," while the other three forces are still combined
answer
GUT Epoch
question
4 Primary pieces of evidence that support the Big Bang Theory
answer
1) detection of the cosmic background radiation which was predicted to exist by George Gamow 2) Gamow also predicted that the nucleosynthesis stage of the Big Bang would produce a ratio of 75% H to 25% He of primordial matter. 3) Hubble and Slipher measured redshifts from almost all galaxies which infers the universe is expanding. 4) The detection of intergalactic primordial helium
question
What time does a first quarter moon set at?
answer
midnight
question
As viewed from Earth, the angle between the Sun and the Moon in the sky during the Full Moon phase is what?
answer
180 degrees
question
when did the big bang happen
answer
18.82 billion years ago
question
slipher is the first to measure what?
answer
redshifts of spiral nebula galaxies
question
COBE
answer
cosmic background explorer; smoot and mather use COBE to show anisotropy
question
WMAP
answer
wilkerson microwave anisotropy probe ; launched to study CMBR in more detail shows where gravity formed starts and galaxies -blue= cooler areas
question
what temperature was csmic microwave background radiation discovered at
answer
2.7 K
question
Elementary particles
answer
fundamental building blocks; cant be broken up -Electrons, muons, neutrinos, quarks
question
protons are not
answer
elementary
question
protons are made up of
answer
quarks
question
the universe is a gravitations singularity called
answer
initial singularity
question
initial singularity
answer
point of infinite density before quantum fluctuations that caused the BB and subsequent inflation that created the Universe
question
what periods are we still in ?
answer
-Stelliferous Era -galaxy formation and evolution
question
how many galaxies in our local group?
answer
50- milky way and andromeda are the largest
question
is radio waves frequency low or high?
answer
low and they can travel through anything
question
on the absorbtion spectrum blue/violet are
answer
strong and hot -bigger falls
question
on the absorbtion spectrum red is
answer
weaker and cooler -smaller falls
question
brightest apparent magnitude is a
answer
-30 (our sun is a -26) -dullest is 30 (hubble space telescope is close)
question
Closest star system to ours
answer
Alpha Centauri
question
how far away is alpha centauri?
answer
4.3 light years -made up of 3 stars: alpha centauri a, b, and c
question
S.E.T.I
answer
search for extraterrestrial intelligence, monitors electromagnetic radiation for signs of transmission from civilizations on other planets
question
virus that parasitizes a bacterium by infecting it and reproducing it
answer
bacteriophage
question
planet orbiting a star other than the sun
answer
exoplanet
question
microbes that live in extreme conditions of extreme temperature, acidity, radioactive areas, or chemical concentration
answer
extremophile
question
unit of measurement equal to 149.6 million kilometers, the mean distance from the center of the earth to the center of the sun
answer
astronomical unit (AU) -1 AU earth orbit around the sun -isnt a perfect circle
question
ellipse, parabola, hyperbola
answer
conic sections
question
a subatomic particle with no electric charge very little mass, important in nuclear reaction
answer
neutrino
question
one of the four fundamental forces that govern the universe play a role in the radioactive decay
answer
weak force
question
binds quarks together in clusters to make more similar subatomic particles like protons and neutron it also holds together atomic nucleus and underlies interactions between all particles with quarks
answer
strong force
question
the force exerted by the electromagnetic interaction of electrically charged or magnetically polarized particles or bodies
answer
electromagnetic force
question
dull glow which lights up the unlit part of the moon because the sun's light reflects off the earths surface and back onto the moon
answer
earth shine
question
a subatomic particle such as an electron, muon or neutrino that does not take part in strong interaction
answer
lepton
question
- when a particle and an antiparticle collide they form energy o They collide so violently that protons and neutrons cannot exist as they are being fragments into quarks
answer
particle amihilaton
question
A subatomic particle, such as a photon that has zero or integral spin
answer
boson
question
- any subatomic particles that are made up of quarks and are subject to the strong force
answer
hadron
question
a stable subatomic particle with a charge of negative electricity, found in all atoms and acting as the primary carrier of electricity in solids o Orbits nucleus
answer
electron
question
elementary particles carrying a fractional charge o Predicted to come in pairs with similar mass but opposite charge o Make up the protons and neutrons of hadrons
answer
quarks
question
any substance that when combined with an equal amount of matter results in the complete and direct conversion of all substances to energy composed of anti particles
answer
anti matter
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New