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266 Cards in this Set

  • Front
  • Back
the streak of light produced as matter in the Solar System falls into the Earth's atmosphere
the temporary icandescence (light) from meteors results from
atmospheric friction
matter revolving around the sun or any object that is too small to be called an asteroid or comet
a meteoroid that reaches the surface of the earth without being completely vaporized
when a meteor enters the atmosphere, friction causes _____ of its surface (it burns up)
if a meteor is small (fist-size) it ________ before hitting the ground
___ million meteors enter the Earth's atmosphere everyday...most burn up and about _ million kgs of dust settles to the eart's surface
the three broadest groupings are
the most common meteorites are ____ which are stony meteorites (dated to be 4.55 billion yrs old= age of solar system)
iron meteorites consist primarily of
iron-nickel alloys
meteorites contain evidence of changes that occurred on the
parent bodies from which they were removed or broken off
pallasites are stony iron meteorites composed of
olivine enclosed in metal
meteors often occur in ____ or ___
showers or swarms
The gap between Mars and Jupiter was of great historical interest due to the
Bode-Titus relation
Most asteroids are contained within a main belt that exists between
the orbits of Mars and Jupiter
If the estimated total mass of all asteroids was gathered into a single object, this object would be
if the estimated total mass of all asteroids was gathered into a single object, this object would be - less than 1,500 kilometers across
the ____ are the two stable points in the gravitational attraction between Jupiter and the Sun
Lagrangian points in the Trojan family
The Apollo family of asteroids is ?
asteroids with near-solar orbits - objects with highly eccentric orbits that are Earth-crossing.
In 1931 the asteroid Eros came within
23 million km
In 1988 a 20km object came within
1.1 million km
In 1972 a 10 km object came within
60 km
In 1968 the asteroid Icarus came within
6.4 million km
Amor family asteroids
Mars-crossing orbits
Asteriods have 3 types
C-type or carbonaceous, S-type or silicate and M-type or metal.
Toutatis is a ___________ with a 4 yr orbit just inside earths orbit
near-earth orbit
most geologically diverse of large asteroids
small, fragile, irregularly shaped bodies composed of a mixture of non-volatile grains and frozen gases
comets had highly _______ orbits
surrounding cloud of diffuse material on a comet
the ____ grows in size and brightness as the comet approaches the sun
the ____ and the ____ constitute the head of the comet
coma and the nucleus
comet's dust tails are caused by
the sun's radiation pressure and solar wing
each time a comet visits the sun it loses some of its ________
comets have their orgin in the giant ____ ____
oort cloud
perturbations from _____ _____ cause the comets in the oort cloud to fall into the solar system
nearby stars
if a comet passes to close to _____ the orbit is converted into a highly eccentric ellipse and the comet becomes periodic
the largest planet in the solar system
jupiter's density is close to that of
jupiter is composed of mostly
hydrogen and helium
HCNO compounds make-up most of the
comets, moons, and rings around the Jovian worlds
the beginning of the formation of Jupiter and other Jovian worlds starts with the accrection of
ice-covered dust
since heavier elements sink to the core we expect the core region of JUpiter to be
2 exterior aspects of Jupiter
1) brightly colored latitudinal zones
2)dark belts and thin bands dotted with numerous storms and eddies
due to ______ ______, the equatorial zones and belts rotate faster than the higher latitudes and poles
differential rotation
the zones and belts are zonal ___ ____ moving with velocities up to _____ miles per hr
jet streams/400
the most obvious feature on Jupiter is the ____ _____ ____ which i actually the
Great Red Spot/ top of a large cyclone twice the size of the Earth
gas planets do not have solid surfaces but rather build-up in _______ and ______ as one goes deeper towards the core.
pressure and density
atmosphere of jupiter is so dense and cold that it behaves as a ___ rather than a ____
fluid, gas
when a fluid slips by a second fluid of a different density and produces wave-like features at the boundary of the two fluids
viscous flow
A second pattern is produced by a stream of fluid in a constant medium, called _____ _____
turbulent flow.
The stream breaks up into individual elements, called _____ which can develop into _____
eddies/ cyclones
Cyclones develop due to the _______ _______ where the lower latitudes travel faster than the higher latitudes producing a net spin on a pressure zone.
Coriolis effect
The Great Red Spot is a large high pressure storm that has lasted over _____ yrs
The energy needed to power all the turbulence in Jupiter's atmosphere comes from __________________, on earth the energy to power our storm systems comes from __________
heat released from the planet's core.// sunlight
Jupiter is highly
oblate (flattened)
Since Jupiter is oblate and has a high rotation rate, we know
it has a very small core
20,000 km below Jupiter's atmosphere, liquid hydrogen is compressed into a
metallic state
Jupiter is 20 degrees warmer than it should be because
it radiates about twice as much energy as it receives-extra heat is leftover from the time of formation
if jupiter were _____ times more massive our solar system would have 2 stars
two components to Jupiter's radiation output...
a thermal and non-thermal component.
A thermal component is associated with
the leftover heat of formation
The non-thermal component is associated with radiation that does not follow a _____ ____but follows what is know as a power-law spectrum associated with _____ _______
Planck Curve/synchrotron radiation.
______ _____ occurs when a charged particle encounters a strong magnetic field with a result of a distinct radio signature that reveals the strength of the magnetic field
synchrotron radiation.
The magnetic field of Jupiter is ________ times stronger than the Earth's magnetic field
he origin of Jupiter (and other Jovian planets) strong magnetic field is the____ _____ _____ that surrounds Jupiter's rocky core
metallic hydrogen shell
A strong magnetic field can capture ______ ______ which are trapped in the inner magnetic belts and are reflected back and forth between the north and south magnetic poles
charged particles
A visible result of the charged particle interaction is ______ or ______ _____ on Jupiter.
aurora or northern lights
The interaction of Jupiter's strong magnetic field and nearby space produces a region known as Jupiter's...
features of Jupiter's magnetosphere
# North and South magnetic poles
# current sheet along the magnetic equator
# plasma torus associated with Io's orbit
# magnetopause - the boundary where the magnetosphere encounters the solar wind
the boundary where the magnetosphere encounters the solar wind
the current sheet between Jupiter and IO is intensely
the second larges planet
Much of what is known about the planet is due to the _______ explorations in 1980-81
atmosphere of saturn is composed of _______ and small amounts of ____ and ______
hydrogen/ helium and methane
saturn is the only planet less dense than _____
One of the more obvious features is Saturn's _____ _____, Inclined at ___ degrees
ring system/ 27
On Saturn, the low mass means less _____ _____ and the atmosphere is ______
surface gravity/thicker
winds on saturn ca blow up to ______ miles per hr
Saturn emits ___ times more energy than it receives.
Saturn has a warmer core due to
helium rain
saturn is more _____ than jupiter
Saturn's magnetic field is ______ times the strength of the Earth's magnetic field, but less than ___ of Jupiters
8,000/ half
the strength of a magnetic field is proportional to the size of the____ ___ ____ and the speed of ________
core or mantle/ rotation
Saturn's magnetosphere is smaller and there is no current sheet because (2)
1) the magnetic field is less strong, therefore the magnetosphere is smaller, and 2) the rings of Saturn serve to damp out the charged particles that we saw associated with Jupiter's system
All the Jovian worlds have ring systems due to the massive _____ ______ associated with the gas giants
tidal forces
When a moon or comet approaches within the ____ ____ of a planet, the tidal forces overcome the internal forces and disrupt the moon/comet
Roche limit
We know that that the rings are not solid or liquid because of
Doppler measurements
The brightest rings are made of house-sized blocks of
The faintest rings are made of
icy dust
Saturn's rings are the most prominent and were show by Voyager to be composed of
hundreds of ringlets
Gaps in the rings are due to ____ ______ with the outer moons.
orbital resonances
______ ______ occurs when the orbital period of the moon and the orbital period of a ring particle are in a fractional configuration
orbital resonances
_______ _____ work in pairs on the inner and outer edge of rings to gravitational push and pull ring particles- resulting in confining the ring particles within their orbits
Shepherd moons
____ _____ are thought to be the shadows of smaller particles levitating a few tens of meters above the rings due to electrostatic forces (
radial spokes
ringlets that are disturbed, discontinuities in ringlets, and gaps in the diffuse inner strands are due to the influence of
6) Any formation theory of the Solar System must explain the regularity of the orbits. In particular, it must address:

a) all planets have prograde orbits b) all planet have low eccentricity c) most planets have prograde rotation d) all planet orbits have low inclination e) all of the above
e) all of the above
8) Ammonia is

a) H_2O b) CO_2 c) NH_3 d) N_2 e) CH_4
c) NH_3
10) How long does it take a radio (or light) signal to travel to the Moon and back?

a) 1/2 sec b) 30 secs c) 1 hour d) 1 day e) 1 year
a) 1/2 sec
11) The planet with the most moons is

a) Saturn b) Pluto c) Earth d) Venus e) Mars
13) Suppose the Earth's axis is tilted to 40 degrees, how would this effect the time from sunrise to sunset in the sumer?

a) they would be shorter b) they would be longer c) they would be the same d) they would only be longer for people on the equator e) they would only be shorter for people on the equator
b) they would be longer
22) A silver ball has

a) a lower albedo than the Moon b) a higher albedo than the Moon c) a lower temperature d) a higher temperature e) a redder color
b) a higher albedo than the Moon
30) Why does the Moon have no atmosphere?

a) too little gravity b) too high temperature c) too fast rotation d) a and b e) a and c
d) a and b
37) The largest component of outgassing is

a) H_2O b) CO_2 c) N_2 d) Ar e) SO_2
46) The region of the Moon with the oldest age are

a) highlands b) maria c) crater rims d) domes e) rilles
48) Small worlds

a) cool fast, have thick crusts b) cool slow, have thick crusts c) cool fast, have thin crusts d) cool slow, have thin crusts e) bake, have crusts made with cheese
a) cool fast, have thick crusts
51) The temperature of the core of the Earth is around

a) 1,000K b) 5,000K c) 20,000K d) 273C e) 1000F
54) Radioactive dating uses the fact that

a) some elements emit electrons at a set rate b) all elements gain neutrons and increase in mass c) some elements glow from radioactivity d) some elements emit x-rays which can be detected on film e) some elements emit helium nuclei and convert into light elements
e) some elements emit helium nuclei and convert into light elements
60) Heat to power tectonic activity comes from

a) leftover heat of formation b) radioactive decay c) solar energy d) a and b e) b and c
d) a and b
64) We study the planets to

a) gain knowledge of how the Earth will evolve b) to learn how to exploit the resources of other planets c) to learn how to travel to other planets d) to experiment on the environments where humans can survive e) satisfy our curiosity
a) gain knowledge of how the Earth will evolve
71) A strong planetary magnetic field indicates

a) a large Fe core b) a fast rotation rate c) both a and b d) either a or b e) none of the above
d) either a or b
78) Secondary atmospheres are rich in

a) H_2O, CO_2, SO_2 and N_2 b) CH_4, CO_2, SO_2 and N_2 c) H_2O, NH_3, SO_2 and N_2 d) H_2O, CO_2, CH_4 and N_2 e) H_2O, CO_2, SO_2 and H_2
a) H_2O, CO_2, SO_2 and N_2
80) The surface temperature of a planet is determined primarily by

a) distance from the Sun b) thickness of the atmosphere c) greenhouse effect d) presence of oceans e) all of the above
a) distance from the Sun
84) A hydrogen atom is composed of

a) one proton, one neutron, one electron b) one proton, one neutron, two electrons c) one proton and one neutron d) one proton and one electron e) one proton, two neutrons, one electron
d) one proton and one electron
86) Oxygen is missing in most of the planet's atmosphere because

a) it is not an outgassing product b) it escapes into space c) it is absorbed by water d) it is highly reactive e) it is used by plants
d) it is highly reactive
91) The half-life of a radioactive substance is

a) 1/2 the mass of the nucleus b) the lifetime of a nucleus c) the number of stable isotopes in the sample d) the time need for half the nuclei to decay e) all of the above
d) the time need for half the nuclei to decay
93) Methane is

a) H_2O b) CO_2 c) NH_3 d) N_2 e) CH_4
e) CH_4
94) Under extremely high temperatures and pressures, rock will

a) become a plastic-like substance b) become liquid c) become a solid d) boil e) freeze
c) become a solid
97) The thickness of a planet's crust is primarily determined by

a) its cooling rate b) its chemical composition c) distance from Sun d) presence of a moon e) none of the above
a) its cooling rate
______ ______ created and shaped the Solar System
natural forces
Any model or theory for the formation of the Solar System must have a set of explanations for
large-scale and small-scale properties.
the large-scale properties of the solar system are
1. the planets are isolated in orderly intervals
2. orbits are nearly circular
3. orbits are in the same plane
4. all planets revolve prograde
the small-scale properties of the solar system are
1. most planets rotate prograde
2. the systems of moons can be divided into regular objects (spherical) with direct orbits versus irregular objects with eccentric orbits
3. terrestrial planets have
1. high densities
2. thin or no atmospheres
3. rotate slowly
4. rocky, poor in ices and H/He
4. jovian worlds have
1. low densities
2. thick atmospheres
3. rotate rapidly
4. many moons
5. fluid interiors, rich in ices, H/He
5. most of outer SS objects (not just jovian worlds) are ice-rich
All indicators point to a single formation event about ____ billion years ago.
the Solar System is not a static system, it is ______
ociology of science requires that a hypothesis be tested and confirmed by many scientists since the creator of the hypothesis has a strong _______ ________ to his work.
psychological attachment
One of the earliest theories for the formation of the planets was called the
encounter hypothesis
the encounter hypothesis explains (2)
-why the planets all revolve in the same direction
- why the inner worlds are denser than the outer worlds
two major problems for the encounter theory
- hot gas expands, not contracts
-encounters between stars are extremely rare
in the _____ theory, the whole Solar System starts as a large cloud of gas that contracts under self-gravity
nebular theory
nebular theory- Conservation of _______ _____ requires that a rotating disk form with a large concentration at the center- w/i the disk planets form
angular momentum
two flaws in the nebular theory
- a majority of the angular momentum in the solar system is held by the outer planets
- the mechanism from which the disk turns into individual planets
The current working model for the formation of the Solar System is called the
protoplanet hypothesis.
Since force of gravity is proportional to mass, the ______ ________ are accreted first
largest planetesimals
Uranus is the...?
seventh planet from the Sun and the third largest in the solar system
The lenght of a day on Uranus is
17 hours 14 minutes
Uranus is distinguished by the fact that it is...
tipped on its side with a rotational axis that is inclined to the orbit by 98 degrees
The atmosphere of Uranus is composed of
83% hydrogen, 15% helium, 2% methane and small amounts of acetylene and other hydrocarbons
Winds at mid-latitudes on Uranus move in the direction of _________. These winds blow at velocities between __ and ___ miles per hour.
The planets rotation, 90,360
Uranus'atmosphere energy system is much less active because
it lacks an internal energy source such as Jupiter and Saturn
Neptune is the
outermost planet of the gas giants
A day on Neptune is
16 hours and 6.7 minutes long
Most of Neptunes moons were found by...
Describe Neptunes atmosphere
Neptunes atmosphere is dynamic with large dark spots with storms in the center. The storms are powered by absorbing smaller storms. It also has long bright clouds.
Neptune emits ___ times more energy than it receives from the Sun
in the protoplanet hypothesis, where did all the outgassing material come from?
comets that fall from the outer Solar System after the planets form
the ______ worlds were the most efficient at capturing planetesimals
the Solar System divided into large proto-planets and smaller and smaller planetesimals which eventually became the numerous ______ we see today
leftover large bodies were captured as moons or ejected by gravity assist into the
oort cloud
the only remaining problem in the protoplanet theeory is
the distribution of angular momentum
the mechanism of choice by which the sun has lost angular momentum is
magnetic braking
As the solar wind leaves the solar surface, the charges particles are ``dragged'' by the magnetic field, which in turn slows down the Sun's _________
the outer solar system is still strange, especially the properties of
one explanation is that the outer solar system ______ to their present positions
Early in the formation of the Solar System, there were lots of _____-sized to _____-sized bodies, especially in the outer SS
A large planetesimal that crosses near Neptune will lose some energy, fall down near Jupiter, gain energy to be ejected into the Oort Cloud which will have the effect of..
decreasing the size of jupiters orbit and expanding the size of Saturn, Uranus, and Neptunes orbits
There are now numerous verified _____ _____ ____ that have Jupiter size planets in orbit around them.
solar type stars
_____ _______ is used to detect the periodic velocity shift of the stellar spectrum caused by an orbiting giant planet
Doppler spectroscopy
stars that move toward us, then away from us, then toward us again wobbling with periodic motion are
gravitationally bound to another object.
The periodicity of the Sun's motion is the same as the orbital period of Jupiter: one cycle takes about
12 years
a distant planet passing in front of its star, providing direct and independent confirmation of the existence of extrasolar planets
HD 209458
none of the 18 other extrasolar planets discovered has had its orbital plane oriented _______ __ _____ so that the planet could be seen to transit the star
edge-on to Earth
With the orbital plane of the planet known, the astronomers for the first time could determine precisely the
mass and density of the planet
the planet's mass is only ___ percent of Jupiter's mass, its radius is ____ percent bigger than that of Jupiter
water exists as a liquid between _____K and ____K unless the pressure is too low
the region on the solar system where the temp is in the range of liquid water
habitual zone
the fraction of incident light reflected, not absorbed
the albedo
The albedo of the Earth is ____; that of Venus is ____; that of the Moon is about _____
the earths crust became stable ___ billion years ago
Life appeared around ___ to ___ billion years ago, which is quite fast in astronomical terms
3.6 to 3.9
the evolution of life requires two elements
energy and a medium for growth
sunlight provides the energy needed for (2)
-food manufacture
-molecular construction
water provides the raw material for
protein construction
small, highly reactive molecules composed of 20 to 30 HCNO atoms
amino acids
When amino acids link together in strings they form
huge tides from the Moon produced _____ ______ ______, which would fill and evaporate on a regular basis to produce high concentrations of amino acids, who then linked themselves into macromolecules
inland tidal pools
Living organisms are the supreme example of _____ _______
active matter
Every organism is unique, both in ____ and ___________
form and development
The best way to study chaotic behavior, also called nonlinear behavior, is with the use of a
life on Earth is an intricate network of _______ _______ organisms held in a state of dynamic balance
mutually interdependent
The ingredients for life are:
1. energy source
2. supply of nutrients (building blocks)
3. self-regulating mechanisms
A large number of complex chemical reactions is the underlying process that we call
long chains of nucleic acids were formed which developed into ____ and ____
RNA and DNA are molecular codes for the production of
coated RNA and DNA packages are called a
A virus is halfway between life and non-life meaning
non-living when in isolation, but adapting living characteristics in interaction with other virus' or cells
various virus' to take on specialized tasks which eventually combine to form the first
With the development of cells, life took on an explosive evolution into more diverse forms, invading new
the current amount O2 requires a constant process of replenishment which is
What is weird about Neptunes and Uranus' magnetic fields?
they are not aligned with the rotational axis of the planet and may be unstable
Describe Pluto
Pluto is a binary planet system that orbits around Charon.
What is odd about Pluto?
it is a Terrestrial world out beyond the Jovian worlds
Plutos surface is ...
covered with methane ice and that there is a thin atmosphere that might freeze and fall to the surface as the planet moves away from the Sun.
Pluto is thought to reach as low as
Charons surface appears to be
covered with water-ice
As Pluto/Charon moves away from the Sun what happens?
the methane haze ``snows'' onto the surface and that helps rebuild the surface features
what is the Kuiper Belt?
a group of about 70,000 small bodies that extend from the orbit of Neptune that are confined within a thick band around the ecliptic
It si beleived that the Kuiper Belt is a resevoir for ...
short period comets
The sun is a...
self-luminous ball of gas held together by its own gravity and a dwrf compared to other supergiant stars.
The Suns most outstanding feature is...
the fact that it emits huge quantities of electro-magnetic radiation creates more energy on Earth in 30 minutes than all of human civilization.
What are the six regions of the Sun?
the fact that it emits huge quantities of electro-magnetic radiation
Stars form from
clouds of gas and collapse under self-gravity but when potential energy is converted to kinetic energy during the collapse the collapse is stopped.
the fact that pressure balances the self-gravity
hydrostatic equilibrium
the amount of energy generated equals the amount radiated away...
thermal equilibrium
Only organisms which were able to utilize the visible portion of the spectrum survived =
green plants and plankton
_______ is a change in the gene pool of a population over time
a hereditary unit (the microscopic `atom') that can be passed on unaltered for many generations
the set of all genes in a species or population (the macroscopic `object')
gene pool
a prime example of observed evolution is...
the english moth, biston betularia
populations evolve, not _______
When a population is evolving, the ratio of ______ _______ _______ is changing
different genetic types
the process of evolution can be summarized in 3 sentences...
Genes mutate. Individuals are selected. Populations evolve
an English clergyman, whose writings on population growth had a strong influence on the theory of evolution by natural selection
Thomas Malthus
Malthus believed that poverty, disease, and famine was a natural and inevitable phenomenon, leading to a "______ __ _______"
struggle for existence
Darwin's book
on the origin of species
in his book, darwin proposed a mechanism for evolution called
natural selection
_______ ________ is the only mechanism of adaptive evolution; it is defined as reproductive success of classes of genetic variants in the gene pool.
Natural selection
_______ _______ is natural selection operating on factors that contribute to an organism's mating success
sexual selection
_________ removes the extremes end of a trait distribution.
the resistance of the solar envelope to the flow of photons (how fast the energy is released)
how energy is transported from the core to the photosphere (convection or radiation)
energy transport
in the case of stars, energy is produced by thermonuclear fusion
energy production
________ is the heart of the solar process
energy generation
The primary output from nuclear reactions are
photons in the form of gamma-rays
What are Solar oscillations?
the Sun is not in perfect balance but oscillates with periods from 5 to 160 minutes
What are Solar Neutrinos?
solar neutrinos created during the proton-proton chain reactions are a direct look into the current reaction rates. Large underground neutrino detectors, such as the Super Kamiokande in Japan, are currently detecting less than a 1/3 of the number of neutrinos then what is predicted by the equations.
What is the ``surface'' of the Sun known as?
the Photosphere
The top of the photosphere is about ____ K and has less luminosity because it is at a ______?
4000K, lower temperature
The bottom of the photosphere is about _____K?
The Suns photosphere has 3 main features ...
1. faculae - large, bright regions
2. granules - small (1000 km wide), bright regions that change brightest on the order of several minutes = tops of convection cells
3. sunspots - dark regions that travel in pairs (north and south magnetic poles)
The typical lifetime of a sunspot is
one or two solar rotations.
______ _______ would occur if individuals at one end of the normally distributed curve are favored
Directional selection
_______ _______ would occur if selection simultaneously favored individuals at both ends of the curve, resulting in a tendency for the curve to become bimodal
Disruptive selection
Most of human evolution involves _______ ______
physical evolution
Around __ million yrs ago, a tree-dwelling primate developed: (3)
13 million year
1. steroscopic vision
2. high mobility (upright stance)
3. opposable thumbs
______ ______ was a response to environmental changes in East Africa at the time- to see over tall grasses
upright walking
out first direct ancestor, australopithecus africanus, appeared ___ million years ago
3.5 million
_____ _______ increased to process more complicated visual information and due to increased physical body size
brain capacity
A side benefit from increased brain size was (2)
1) profit from experience (memory/learning) and 2) the ability to choose between alternatives (reasoning)
The idea that man evolved a large brain first was propagated for most of the 20th century by the famous
Piltdown Hoax.
most of the physical attributes of human form (upright walking, jaw and teeth structure, pelvic and leg formation) came before
the brain size evolved
We know that every living human is the direct descendent of a single Homo Sapian woman who lived in
Africa 150,000 yrs ago
Why is the solar magnetic field on the sun different that other magnetic feilds.
it is a surface magnetic field
How long does the sunspot cycle take?
11 years
Where is the chromosphere located?
above the photosphere
Describe the chromosphere and what goes on there.
it is a pinkish atmosphere above the Sun's photosphere that has very hot gasses (20,000K). Solar flares, solar arcs, and prominences happen there.
When is the corona of the sun visible?
During a total eclipse.
The corona gas is ______ and is the source of the ________.
extremely hot, solar wind
solar wind is a constant stream moving how fast?
Faster than the escape velocity of the suns gravitational field.
normal evolution has ______ _____ being transmitted by genes
inherited traits
language allows the passing on of information by _______ _____, the process of learning and teaching
behavioral means
______ has some advantage for the survival of our ancestors, therefore natural selection favors genes responsible for such behavior
________ __________, with its global nature, becomes the distinguishing characteristic of humans
Cultural evolution,
______ ______ in meteors must represent samples from the early stages of the Solar System before chemical evolution
amino acids
over _____ pounds of lunar soil was returned by the Apollo missions
an experiment to test for photosynthesis on MArs
Pyrolytic release
an experiment to look for metabolism on Mars
label release
an experiment to test for respiration on Mars
gas exchange
"If there are all these billions of planets in the universe that are capable of supporting life, and millions of intelligent species out there, then how come none has visited earth?" is known as
The Fermi Paradox
Extra terrestials would possess one of three levels of technology
1- civilization similar to our own- using energy resources of planet
2- civilization that uses the energy resources of a star
3- one that would employ the energy resources of an entire galaxy
The idea of self-reproducing automaton was proposed by mathematician
John von Neumann
the ideas of a self-reproducing automaton could
1) perform tasks in the real world and 2) make copies of itself (like bacteria)
The fastest, and cheapest, way to explore and learn about the Galaxy is to construct
Bracewell-von Neumann probes
a payload that is a self-reproducing automaton with an intelligent program (AI) and plans to build more of itself.
A Bracewell-von Neumann probe
Growth of the number of probes would occur exponentially and the Galaxy could be explored in ___ million years.
possible solutions to fermi's paradox
-they do not exist
-they are here
-they exist but have not yet communicated
solutions to Fermi's paradox come down to either
1) life is difficult to start and evolve
2) advanced civilzations destroy themselves on short timescales