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All change for Jupiter's red spots

....there's a serious shake up going on in Jupiter's turbulent atmosphere...

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Mars Express has Phobos in sight

...Mars Express prepares for several close fly-bys of the Martian moon Phobos in the quest to settle debate on the origin of the red planet's two rocky satellites...

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Earth filmed as

alien world

...EPOXI has captured the transit of the Moon as it passes in front of the Earth, an observation that will help scientists develop techniques to study alien worlds...

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Video archive

STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.


STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.


STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

 Full presentation
 Mission film

STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.


Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

 Full coverage

Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

 Launch | Science

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Closing in on Venus

Posted: July 18, 2008

Unexplored regions of Venus will soon be within the reach of Venus Express, which is executing a series of manoeuvres this week to gradually bring it closer to its host planet.

Artist impression of Venus Express swooping over the planet's cloud tops. Image: ESA

Venus Express has been studying largely unknown phenomena in the Venusian atmosphere for over two years, along with the interaction between the solar wind and the planetary environment. Until now, Venus Express has occupied a highly eccentric polar orbit, swooping by the north polar regions at a distance of 250-400 kilometres, and slingshotting around the south polar regions at 66,000 kilometres. This enabled close up views of the global dynamics on the northern hemisphere, and extended observations of south pole phenomenon, such as the evolution of the South Polar Vortex.

By 4 August, the spacecraft will be settled into its new orbit at an altitude of 185-300 kilometres. This modification will enable an in depth study of the magnetic field and the plasma environment deeper in the ionosphere than previously possible.

Close up view of the double-eyed vortex at Venus's south pole. The brighter colours indicate more radiation is coming from the hot layers below. Many intricate sub-structures are visible in the vortex. Image: ESA/VIRTIS/INAF-IASF/Obs. de Paris-LESIA.

In a more ambitious strategy, the spacecraft will be dragged through the thick atmosphere, in order to measure its density and to learn more about drag on the spacecraft's body, which will be measured by the onboard accelerometers. As the next step, Venus Express may test aerobraking, a technique where a spacecraft uses the force exerted by the planet's atmosphere to decelerate, thus significantly changing its orbit, but in a controlled manner.

More about the Venus Express mission can be found on the dedicated pages of the ESA website.