14-20 Flashcards
Who was lowel and what did he do
spent 20 yrs documenting and mapping 437 cannals
None of this is belive dto be correct although his features are documented as true geological structures
What are the faces and pyramids on mars
Face and structures which were debunked by viking 1 in 1976
what was ALH 84001
1.93kg
4.5 b yrs old
thought to have had water on it when it left mars
electron microscope revelaed fossiled bacteria
strong evidence of life on mars
found layered sequances of Ca-Mg-Fe-carbonates
It has been suggested that the carbonates are consisytant with hydrothermal fluids - similar to subaquaous volcanic vents on earth
thought to have been launched by a 1km asteroid 16 million years ago
What is the Zagami meteroite
18 kg thing
1962
belived to come from mars
how do things leave mars
faster than escape velocity - 5km/s
meteroite impact
Why did water disapearfrom mars
most surface water was lost 3.7-3 billion years ago
changes in the core - lost magnetic field and lost oceans
When was the first mars flyby?
1964 - mariner 4 - 21 images
when was the first major mission to mars
Viking project - two orbital and lander craft
1976 - V1 and V2
What were the viking space missions doing>
Pyroltyic release (carbon relases
gas exchange
labled release
what were the results of the Viking experiments
LR - milxed soil with organic nutrients and C14 atoms - if microbes, metabolisation would take place, producing CO2 or methane, which could be measured — It did : 10,000 counts of radio active molecules, higher than the background 50-60
What did the gas spectrometer findings tell us
seoerated water vapour via gas chromotograph and fed the weight to a spectometer
Fe Si and O were found but no Carbon - no organic matter on martian surface
- difficult to explain with the results of the LR
are the results of the viking chemical or biological
chemical
what is the Mars Global Surveyer
since 1999, 240,00 images of mars
south - rough and heavily creators - a number of volcanoes - shows geological activity
north - younger with fewer creatrts
what is the Mars Pathfinder and Sojourner
landed in 1977
wheeled robic rover called sojourner
Sent 2.3 billion bits of information
16,500 pics
8.5 million measurements
Showed that the core of mars may have an iron core of between 1300km and 2400km
what is the tilt of earth and mars
axis tilt is 25 d, earth is 23.5
what are seasons and weather on mars
southern hemishphere has more extreame seasons
winter - temp drops so low that co2 condenses into dry ice at the poles
summer - CO2 sublimates and water ice remains
What happens to the pressure at the poles on mars
pressure increases at summer pole and decreases at winter pole
What is the unusual weather on mars
stong winds from the cycling of CO2 can cuase large storms - dust devils - spirlaing upwards
why does mars atmousphere leak out
leading theory -
weak gravity
lack of global magnetic foeidl
left atmoushere vulnerable to pressure from solar windwha
twhat is the history of water on mars
3800 m yrs CO2 gradually disappears uasing lakes and rovers to freeze
3100 m yrs ago - atmoushphere thins, no liquid water can survive
1500 m yrs ago - atmous very thin, no liquid water
what is the mats odyssey
robotic spaxe craft orbiting mars
spectometer and themal imager
found water ice in upper 1m of soil in south pole (cant see deeper than 1m )
How much ice on mars
The amount of hydrogen detected by the gamma-ray spectromter indicates 20-50% ice by mass in the lower layer
what is the MRO
mars reconnaissance orbiter
finds the strongest evidnce that salty liquid water flows intemitantly
what is curiosity
landed in 2012 in gale creater - collecting data for a manned mission
tell me about jupiter
rotation period - 9h55
mainly H and He
67 moons and thin ring systems
tell me about saturn
10h 34 rotation
M<ianly H
H atoms packed so close together, atoms start sharing electons and behaves like a storm
62 moons and extensive ring system but only 20m thick
Tell me about uranus
17h14m
mainly H and He
27 monns and 2 sets of rings
Tell me about Neptune
rotation period = 16.1h
H and He
14 moons and thin rings
Where are the gas gianets located
outside 2AU
planet surfaces are too cold for liquid water
what is the roche limit
the smallest disatmace which moon can orbit wirthout being torn apaert by the gravity of the planet
the orbiting speed eventually cuases rthe material to forma ring
what is Ganymede
largest moon in soalr system around jupitr
what is titan
largest moon of saturn
discovered in 1655
atmoushphere discovered in 1944
2nd largest moon in solar system
5000 km di
14% gravity of eatrth
-180 degrees
no magnetoc field
dense atmoushphere 0 nitogenm, methane and traces of hydrocarbons
surface pressure is 150% of earth
Likley has a subsurface ocean 60km below
1.88 g/cm cubed density
Not only ice - likley to ahve rock
outside habitable zone
the future:
Likley to become habitable
methane will create green house
water will be supported on the surface
amonia will slow chemical reactions
what is titans atmoushphere like
methane
- finsing is supring as sun radition would have tuend it all inot hydrocarbons, so the methan must be being replenished - cryovolcanoes?
There may be seas of ethane
layer 1 - 600km, where UV breaks down methan and N - react to form more complex organic molecules
these small particles collide and fall deeper to the lower main haze layer, layer 2
what were the cassini/Huygens mission
mission to titan
took 7 years
saw pheobe on the way in
huygen probe - no liquids
cassini orbiter - found lake in north polar region
how to detect extrasolar planets
directly - piccys or spectra of ecoplanets
indirectly - measurement of star properties may reveal the effects of orbiting planets
tell me about direct detection of planets
works when planet
close
large
far from host star
hot and bright - thermal imaging
examples:
HR8799 - 30 m yr old main sequance star 129 ly away
tell me about indirect methods
astronomy
transitys
doppler shirts
pulsar timing
microlensing
what is proper motion
apparent angular motion of stars across the sky, measured with respoect to more distant stars
What is europa
moon
tidally locked to jupoiter
