Venus, the Sister Planet of Earth
This animation of wind circulation on Venus is composed of images taken by the Visual and Infrared Thermal Imaging Spectrometer (VIRTIS) on board ESA’s Venus Express between April 2006 and June 2007.
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Recognized as a terrestrial planet, Venus has the highest atmospheric density of all the terrestrial planets consisting mainly of carbon dioxide. Called the sister planet of Earth, it has been said that “it has no carbon cycle to lock carbon into rocks and surface features nor organic life to absorb it in biomass.” In April of 2006, first images of the wind circulation on Venus were composed by ESA’s Venus Express and its onboard Visual and Infrared Thermal Imaging Spectrometer (VIRTIS) in a much more photogenic viewpoint than ever before.
The VIRTIS observations provided us with 3D Venusian images showing for the first time the winds for an entire planetary hemisphere, obtained at the infrared wavelength of 1.74 micrometers. This allowed for tracking of the clouds at the cloud layer’s lower boundary during the night-side, or the red part of the globe in the above illustration. The grey part of the illustration, or its day-side, was obtained in the near-infrared and in the blue ultraviolet areas. Below are the major parts of VIRTIS as listed by ESA:
ASPERA (Analyser of Space Plasma and Energetic Atoms)
ASPERA will investigate the interaction between the solar wind and the atmosphere of Venus by measuring outflowing particles from the planet’s atmosphere and the particles making up the solar wind. It will study how the molecules and ions escape the planet.
MAG (Venus Express Magnetometer)
Venus has no detectable internal magnetic field, and the field that exists around the planet is entirely due to the interaction between the solar wind and the atmosphere. The MAG magnetometer will study this process and will help in understanding the effect this has on Venus’s atmosphere, for instance the atmospheric escape process.
PFS (Planetary Fourier Spectrometer)
PFS will be able to measure the temperature of the atmosphere between altitudes of 55–100 kilometres at a very high resolution. It will also be able to measure the surface temperature and therefore be able to search for volcanic activity. In addition to its temperature measurements, PFS will be able to make composition measurements of the atmosphere.
SPICAV/SOIR (Ultraviolet and Infrared Atmospheric Spectrometer)
SPICAV assists in the analysis of Venus’s atmosphere. In particular, it will search for the small quantities of water expected to exist in the Venusian atmosphere. It will also look for sulphur compounds and molecular oxygen in the atmosphere. It will determine the density and temperature of the atmosphere at 80–180 kilometres altitude.
VeRa (Venus Radio Science Experiment)
VeRa uses the powerful radio link between the spacecraft and Earth to investigate the conditions prevalent in the ionosphere of Venus. Scientists will also use it to study the density, temperature, and pressure of the atmosphere from 35–40 km up to 100 km from the surface, and to determine roughness and electrical properties of the surface. It will also allow investigations of the conditions of the solar wind in the inner part of the Solar System.
VIRTIS (Visible and Infrared Thermal Imaging Spectrometer)
VIRTIS will be able to study the composition of the lower atmosphere between 40 kilometres altitude and the surface. It will track the clouds in both ultraviolet and infrared wavelengths and allow scientists to study atmospheric dynamics at different altitudes.
VMC (Venus Monitoring Camera)
VMC is a wide-angle multi-channel camera that will be able to take images of the planet in the near infrared, ultraviolet and visible wavelengths. VMC will be able to make global images and will study the cloud dynamics and image the surface. In addition it will assist in the identification of phenomena seen by other instruments.
This entry was posted on Thursday, September 18th, 2008 at 3:28 pm and is filed under Space Agency News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
