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One year at Venus, and orbiter still going strong EUROPEAN SPACE AGENCY NEWS RELEASE Posted: April 15, 2007 One year has passed since Venus Express, Europe's first mission to Venus and the only spacecraft now in orbit around the planet, reached its destination. Since then, this advanced probe, born to explore one of the most mysterious planetary bodies in the Solar System, has been revealing planetary details never caught before.
Using state-of-the-art instrumentation, Venus Express is approaching the study of Venus on a global scale. The space probe is collecting information about Venus' noxious and restless atmosphere (including its clouds and high-speed winds, as seen from this video obtained with the VMC camera on board) and its interaction with the solar wind and the interplanetary environment. Last but not least, it is looking for signs of surface activity, such as active volcanism. "During one year of observations, we have already collected huge amount of data, which is exactly what we need to decode the secrets of an atmosphere as complex as that of Venus," said Hakan Svedhem, Venus Express Project Scientist at ESA. "Analysing it is an extreme effort for all science teams, but it is definitively paying back in terms of results." The first ever, terrific global views of the double-eyed vortex at Venus' south pole, the first sets of 3D data about the structure and the dynamics of the sulphuric-acid clouds surrounding the planet in a thick curtain, temperature maps of the surface and the atmosphere at different altitudes, are only a few of the results obtained so far. "Continuing at today's rate, and on the basis of what we were able to see so far, there is no doubt that Venus Express will eventually allow a better global understanding of this planet," continued Svedhem. "Not only will planetary science in general benefit from this, but also understanding Venus - its climate and atmospheric dynamics - will provide a better comprehension of the mechanisms that drive long-term climate evolution on our own Earth." The night-glowing 'lantern' of Venus New infrared data is now available about Venus' oxygen airglow - a phenomenon detectable on the night-side that makes the planet glow like a 'space lantern'. "The oxygen airglow was first discovered thanks to ground observations, and also observed by other missions to Venus such as the Russian Venera spacecraft and the US Pioneer Venus orbiter," said Pierre Drossart, co-Principal Investigator on Venus Express' VIRTIS instrument. "However, the global and detailed view we are getting thanks to Venus Express is truly unprecedented."
"The oxygen in the atmosphere of Venus is a very rare element," continued Drossart. At high altitudes in the atmosphere, on the day-side of Venus, the strong flux of ultraviolet radiation coming from the Sun 'breaks' the molecules of carbon dioxide ('CO2') present in large quantity in the atmosphere, liberating oxygen atoms. "These atoms are then transported by the so-called 'sub-solar' and 'anti-solar' atmospheric circulation towards the night side of the planet. Here the atoms migrate from the high atmosphere to a lower layer, called 'mesosphere', where they recombine into O2. By doing this, they emit light at specific wavelengths that can be observed through remote sensing from Earth and with Venus Express," added Drossart. The detection of the airglow, and the capability to follow its evolution in time, is extremely important for several reasons. "First, we can use the distribution and motion of these fluorescent O2 'clouds' to understand how the atmospheric layers below move and behave," said Giuseppe Piccioni, the other co-Principal Investigator on VIRTIS. "In this sense, the O2 airglow is a real 'tracer' of the atmospheric dynamics on Venus." "Second, the analysis of this phenomenon will provide new clues on how its global atmospheric chemistry works - a very challenging task indeed, and still an open field of research," continued Piccioni. "By calculating the speed at which this chemical 'recombination' takes place, we might be able - in the future - to understand if there are mechanisms that favour, or catalyze, this recombination, and learn more about the production and recombination of the other chemical species in the Venusian atmosphere." "Third, the observation of the oxygen airglow also allows to a better understanding of the global 'energetic' exchange between Venus's mesosphere - at upper boundary of which the airglow is situated, with Venus' thermosphere, an even higher layer directly influenced by the Sun." Notes for editors The mechanism for the production of the airglow was described in 1979 by P.Connes, after its emission was discovered through ground-based observations. Venus Express was launched on 9 November 2005 from the Baikonur cosmodrome in Kazakhstan on board a Starsem Soyuz-Fregat rocket. It reached Venus about five months later, on 11 April 2006, when a delicate manoeuvre injected it into orbit around the planet. After a period of commissioning the spacecraft and the instruments, Venus Express started its nominal science operations on 4 July 2006.
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The Russian Soyuz spacecraft with Expedition 15 cosmonauts Fyodor Yurchikhin and Oleg Kotov, along with tourist Charles Simonyi, fly to the space station following launch from Baikonur Cosmodrome.
One of the most daunting yet crucial human spaceflights occurred in December 1993 as the crew of shuttle Endeavour embarked on a mission to repair the Hubble Space Telescope. The observatory had been launched three-and-a-half years earlier with a crippling vision flaw. Two teams of spacewalkers carried out five EVAs to install corrective optics and other equipment to fix the telescope's problems. The astronauts take you through the mission in this post-flight film.
Narrating a highlights film from their STS-51 mission, the shuttle astronauts from Discovery's September 1993 flight describe launching the Advanced Communications Technology Satellite with its Transfer Orbit Stage plus the deployment and retrieval of the Shuttle Pallet Satellite carrying the German ORFEUS ultraviolet telescope. TV and IMAX cameras on the SPAS craft provide stunning views of the shuttle. A spacewalk also occurs to test tools and procedures for the upcoming first servicing of the Hubble Space Telescope.
This documentary looks back at Apollo 7, the first manned flight of the Apollo program. Apollo 7 was designated as the essential engineering test of the spacecraft before the ambitious lunar missions could be attempted.
NASA astronaut Suni Williams will run the Boston Marathon on a treadmill aboard the International Space Station. To preview the event, Williams, an accomplished marathoner, and Expedition 14 commander Michael Lopez-Alegria talk with The Boston Globe and the
New England Sports Network.
International Space Station Expedition 14 commander Michael Lopez-Alegria and flight engineer Suni Williams give a show-and-tell about the exercise equipment and routines aboard the orbiting complex.
After nearly a year in space, the European Retrievable Carrier (EURECA) satellite was plucked from orbit and stowed aboard Endeavour for return to Earth during STS-57. The June 1993 mission also featured the first flight of the commercial Spacehab module outfitted with a range of microgravity experiments for the crew to use. A spacewalk to demonstrate working on the end of the shuttle robot arm was performed as well.
Working in two shifts around the clock, the astronauts of shuttle mission STS-56 conducted extensive observations of the Earth's atmosphere using the ATLAS 2 payload in the spring of 1993. The SPARTAN Sun-studying satellite was deployed and then retrieved during Discovery's flight too. The crew narrates the highlights in this presentation.
