venus express department of physics national tsing hua university g.t. chen 2006/5/11
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Venus ExpressVenus Express
Department of PhysicsDepartment of PhysicsNational Tsing Hua UniversityNational Tsing Hua University
G.T. ChenG.T. Chen2006/5/112006/5/11
Venus Express – Venus Express – First European Mission to First European Mission to
VenusVenus
• Venus Express is a follow on from the Mars Express mission.
• It had been launched on 9 Nov. 2005• After a 153 day trip to Venus, the spacecr
aft entered Venusian orbit on 11 April 2006.
• It reached final operational orbit on 7 May 2006 .
Instrument Objective
ASPERA-4 Neutral and ionized plasma analysis
MAG Magnetic field measurements
PFS Atmospheric vertical sounding by infrared Fourier spectroscopy
SPICAV Atmospheric spectrometry by star or Sun occultation
VeRa Radio sounding of atmosphere
VIRTIS Spectrographic mapping of atmosphere and surface
VMC Ultraviolet and visible imaging
Scientific PurposesScientific Purposes• Atmospheric dynamics• Atmospheric structure• Atmospheric composition and chemistry• Cloud layer and hazes• Radiative balance• Surface properties and geology• Plasma environment and escape processes
Venus ExpressVenus Express• It will gather data for a planned 500 Eart
h days (about two Venusian years).• At its closest, it will reach an altitude of 2
50 kilometers and at its furthest, it will be 66000 kilometers away from the planet.
Questions:Questions:• What are the global characteristics of th
e atmosphere? • How does it circulate?• How does the composition of the atmos
phere change with depth? • How does the atmosphere interact with
the surface? • How does the upper atmosphere interac
t with the solar wind?
Objectives:Objectives:• What is the mechanism and what is the driving force o
f the super-rotation of the atmosphere?• What are the basic processes in the general circulatio
n of the atmosphere?• What is the composition and chemistry of the lower at
mosphere and the clouds?• What is the past and present water balance in the atm
osphere?• What is the role of the radiative balance and greenhou
se effect in the past present and future evolution of the planet?
• Is there currently volcanic activity on the planet?
Golubkina craterGolubkina crater• Golubkina crater on Venus is 34 kilometres in
diameter. Studying the number and size of craters on Venus proves that the surface of the planet is only 500 million years old. Scientists believe that some kind of volcanic catastrophe, 500 million years ago, spilled molten lava across the entire surface of the planet destroying all the older crater