[Space] ESA - Venus Express

[GioFX]

Caratteristiche della missione:


How the mission was named
The name Venus Express comes from the short time to define, prepare and launch the mission. It will take less than three years from the approval to the launch of the mission. To do this, ESA re-used the same design as the Mars Express mission and the same industrial teams that worked on that mission.
Prime contractor: EADS Astrium, Toulouse, France, leading a team of 25 subcontractors from 14 European countries.


Launch date
Launch window is October-November 2005 (Soyuz-Fregat from Baikonur, Kazakhstan).
Launcher: Soyuz/Fregat, built by Starsem, the European/Russian launcher consortium


Launch mass
1270 kg (including 93 kg orbiter payload and 570 kg fuel)
Orbiter instruments: Venus Monitoring Camera (VMC); Analyser of Space Plasma and Energetic Atoms (ASPERA); Planetary Fourier Spectrometer (PFS); Visible/Ultraviolet/Near-infrared Mapping Spectrometer (VIRTIS); Venus Express Magnetometer (MAG); Venus Radio Science Experiment (VeRa); Ultraviolet and Infrared Atmospheric Spectrometer (SPICAV/SOIR);
Spacecraft operations: European Space Operations Centre (ESOC), Darmstadt, Germany


Ground stations
After launch, ground stations at Villafranca (15 m), Spain, New Norcia (35 m), Australia, and Kourou (15 m), French Guiana, will be used for communication and orbit determination.
At Venus, Cebreros (35 m) near Madrid, Spain. The New Norcia antenna will be used to support the Venus Radio science experiments.


Arrival at Venus
April 2006


Journey
The launcher will place the spacecraft into a transfer orbit to Venus. It will travel through space for 162 days and once it is captured by Venusian gravity, it will take five days to manoeuvre into its operational orbit.


Venus Express firsts

• First global monitoring of composition of lower atmosphere in near-infrared transparency ‘windows’;
• First coherent study of atmospheric temperature and dynamics at different levels of atmosphere, from surface up to ~200 km;
• First measurements from orbit of global surface temperature distribution;
• First study of middle and upper atmosphere dynamics from oxygen (atomic and molecular), and nitrogen oxide emissions;
• First measurements of non-thermal atmospheric escape;
• First coherent observations of Venus in spectral range from ultraviolet to thermal infrared;
• First application of solar/stellar occultation* technique at Venus;
• First use of 3D ion mass analyser, high-energy resolution electron spectrometer and energetic neutral atom imager;
• First sounding of Venusian top-side ionospheric structure.

* Occultation can be used to study the atmosphere. Looking at an object like the Sun, Earth or a star through the atmosphere from a limb perspective allows us to analyse how the light emitted by this object is absorbed by the atmosphere, and this tells about the characteristics of the atmosphere itself.

Summary
Venus Express will study our nearest planetary neighbour. It has been built around the design of Mars Express, making it quicker and cheaper to develop. In particular, Venus Express will study the Venusian atmosphere and clouds in unprecedented detail and accuracy. It is ESA's first spacecraft to visit this planet.
With Venus Express, Mars Express and BepiColombo, ESA is the only space agency in the world with current plans to visit each planet in the inner Solar System.

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Brochure ufficiale (PDF): http://esamultimedia.esa.int/docs/VENUSEXPRESSLR.pdf

[GioFX]

Venus Express launch set for 9 November

3 November 2005

In agreement with the European Space Agency, Starsem and its Russian partners have set the launch date for the Venus Express spacecraft. Launch is now scheduled for Wednesday, 9 November 2005, at 03:33 GMT (4:33 CET).

[duchetto]

come mai alla NASA non interessa molto venere?

[GioFX]

Originariamente inviato da duchetto

come mai alla NASA non interessa molto venere?

Beh non è che non interessa proprio... semplicemente hanno già fatto diverse missioni con Mariner e Magellan che hanno studiato Venere, come le russe Venera.

Per l'Europa è la prima volta, e c'è anche da dire che attualmente la NASA è più interessata a Marte, e il budget è limitato anche per loro dati i crescenti costi del programma spaziale.

[CONFITEOR]

Originariamente inviato da duchetto

come mai alla NASA non interessa molto venere?

sono ricchioni

[GioFX]

Roll Out to Launch Pad

05 Nov 2005 18:55

The rollout of the Soyuz launcher carrying the Venus Express Spacecraft has taken place at launch pad number 6 of the Baikonur Cosmodrome on Saturday 5 November 2005 starting at 01:30 UT (07:30 local time), just half an hour before sunrise.

Final preparations of the activity started in the very early morning hours, and included the disconnection of the umbilical connector from the rocket, which had to be completed by 06:00 local time (00:00 UT).

This connection had been used by the Spacecraft team to monitor the status of the Venus Express throughout the night after yesterday's final arming of its onboard batteries.

The Soyuz rocket was installed in horizontal position on the TEW (Transport & Erector Wagon), with the wagon carrying the air-conditioning equipment for the control of cleanliness and temperature under the payload fairing being part of the convoy. It was slowly pulled through the exit doors of the MIK-40 integration building by a Diesel locomotive and commenced its short journey to the launch pad.

The distance between the MIK-40 building and the launch pad is only a couple of hundred meters, and the convoy arrived at the pad at around 08:15 local time (02:15 UT) accompanied by the full Venus Express team launch campaign team walking up to the safety perimeter of the launch tower.

After disconnection of the under fairing air conditioning system the hydraulic system of the TEW was used to tilt the rocket into vertical position, and the Russian specialist team secured the launcher on the 4 support arms of the pad which carry virtually all the weight of the yet unfuelled launcher.

Following the installation of the launcher on the pad the access platforms were closed, enabling physical access to the rocket via a systems of platforms and lift at different levels. The under fairing air conditioning system was reconnected, to guarantee proper environmental conditions for the Venus Express Spacecraft. Access will be required by the Russian teams up until just 45min from the launch to, among other activities, connect and disconnect hoses for propellant loading.

The umbilical links from the Venus Express control bunker, which is located under ground approximately 200m from the launch tower, were checked by the Venus Express team a last time before final connection of the umbilical connector to the rocket was completed around 15:30 local time (09:30 UT).

The launch team located in the bunker switched on Venus Express via the bunker EGSE at around 16:30 local time (10:30 UT) to conduct a last full hardware health check of all vital onboard units before the launch on Wednesday 9 November. This check is performed to ensure full functional integrity of the Spacecraft after its transport from the MIK-112, where the last electrical check had taken place a bit more than a week ago, to the launch pad area.

This health check is still ongoing and is scheduled to finish at around 04:00 on 6 November local time (22:00, 5 November UT) - which will complete a very long first working day of the Venus Express team at the launch pad.


The integrated Soyuz launcher preparing for the tilting of the rocket to vertical position on the launch pad.


The fully integrated Soyuz FG-Fregat vehicle carrying Venus Express, ESA's first probe to Venus, is erected on the launch pad.


The fully integrated Soyuz FG-Fregat vehicle carrying Venus Express stands upright on the launch platform, secured by the four support arms.

[GioFX]

Venus express countdown activities started

8 November 2005

All final countdown activities for the launch of ESA's Venus Express spacecraft, planned for tomorrow, 9 November at 04:33 Central European Time (CET), have started.

The ‘countdown team’, composed of specialists from ESA and industrial partners from Astrium SAS and Alcatel Alenia Space Italia, moved to the bunker near the launch pad at 18:00 CET, from where Venus Express will be made ready for launch.
On arrival at the bunker facilities, the countdown team took over from the last spacecraft ‘babysitting’ team that had monitored the spacecraft status over the last 24 hours.

Actual countdown activities started as planned nine and a half hours before the launch, at about 19:00 CET, and are following a predefined sequence.

During the initial part of this sequence, completed at 21:25 CET, just 7 hours before lift-off, the team has achieved the final configuration of the spacecraft for launch, with the exception of the switch to spacecraft internal power.

This milestone, planned at just 10 minutes before lift-off, means that Venus Express is no longer physically connected to ground power sources and from now on is fully autonomous, as it will be through the course of the whole mission.

[GioFX]

TUESDAY, NOVEMBER 8, 2005

A robotic space probe to examine the mysteries of Venus, the closest planet to Earth, will embark on its mission at 0333 GMT (10:33 p.m. EST) Tuesday night.

The European Space Agency's Venus Express is nestled aboard its Russian Soyuz-Fregat rocket at the Baikonur Cosmodrome in Kazakhstan where countdown activities are in full swing.

The mission was delayed a couple of weeks so technicians could clean bits of insulation that became contamination inside the rocket's nose cone. That work was completed in time for Venus Express to be re-mated to the Soyuz booster last week, and the completely assembled vehicle was rolled out to the launch pad on Saturday morning.

A countdown dress rehearsal was conducted Monday, giving the spacecraft team a final chance to practice events leading up to liftoff.

"We are already receiving live telemetry from the spacecraft in Baikonur on top of the Soyuz launcher via an umbilical cable plugged into launch control and feeding back to ESOC," said Paolo Ferri, Venus Express flight operations director at ESA's European Space Operations Centre (ESOC) in Darmstadt, Germany.

Despite the recent delay, teams have remained busy preparing to see their mission dispatched from Earth.

"We had to do a lot of work to replan the pre- and post-launch activities, so there wasn't too much time to worry while waiting for the new date," said Paolo. "But today, people are extremely motivated."

The lower three stages of the Soyuz rocket will carry Venus above Earth's atmosphere. From there, the Fregat motor will ignite to propel the spacecraft into a preliminary parking orbit. Venus Express and the attached Fregat then coast for more than an hour before the upper stage re-ignites to provide the boost to escape Earth's gravity and begin the cruise to Venus.

The spacecraft should reach our planetary neighbor on April 11, firing its main engine to brake into orbit around Venus.

The mission will perform the most comprehensive examination of the Venusian atmosphere and conduct new observations of the planet's surface.

[GioFX]

Spacecraft sets sail to explore mysteries of Venus

BY STEPHEN CLARK
SPACEFLIGHT NOW
Posted: November 9, 2005

Earth's twin planet has its first new permanent visitor in 15 years on the way after today's successful launch of Venus Express - a European probe that will orbit the second rock from the Sun to study its inhospitable and enigmatic atmosphere.


Venus Express begins its voyage with launch of the Soyuz rocket. Credit: ESA/Starsem

Liftoff of the almost 2,800-pound craft occurred at 0333:34 GMT (10:33:34 p.m. EST Tuesday) aboard a Russian Soyuz rocket topped by a Fregat upper stage. The point of origin was at launch pad 6 at the Baikonur Cosmodrome in Kazakhstan, and the launcher quickly ascended away from the arid central Asian plains through a thin and transparent cloud deck before eventually disappearing from view.

After the three-stage Soyuz system propelled its way to a suborbital trajectory within nine minutes, the Fregat upper stage took over with a pair of burns to first finish the delivery of the probe into a parking orbit about 118 miles above Earth, followed just over an hour later by the maneuver to send Venus Express on its journey toward the inner solar system.

Officials reported a clean separation of the spacecraft one hour and 37 minutes after liftoff, and the performance of the launcher and Venus Express was deemed normal. The Australian New Norcia ground station first made contact with the craft soon after it was released from the Fregat stage, confirming the critical deployment of the solar arrays had occurred, and that all other systems were functioning per the plan, according to controllers at the European Space Operations Center in Darmstadt, Germany.

The launch had been postponed from October 26 when a discovery of contamination was made inside the Soyuz rocket's payload fairing during final preparations a few days prior to the planned launch date. The spacecraft, Fregat upper stage, and fairing were removed and taken to a clean room where the shroud was removed and only large particles were found and easily removed with tweezers, vacuum cleaners, and nitrogen gas airbrushes in the cleaning process.

Testing of the craft was completed before the fairing was re-installed around Venus Express. The entire unit was then transported back to the integration chamber for attachment to the Soyuz rocket.


The Soyuz rocket roars away from the Baikonur Cosmodrome. Credit: ESA/Starsem

Ahead of Venus Express is a five-month, 250 million-mile flight through interplanetary space as it loops inward closer to the Sun before finally reaching Venus in April. The relatively short voyage takes advantage of the close proximity between Earth and Venus this month, an event that occurs in 19-month cycles.

At least two correction burns by the Venus Express propulsion system are planned during the cruise phase of the mission, with the first coming within 48 hours after launch, if needed. Another maneuver in the February timeframe will calibrate the main engine, which is required during arrival at the planet for the make-or-break Venus orbit insertion burn. Other time slots have been reserved in case other adjustments are needed, said Venus Express spacecraft operations manager Andrea Accomazzo.

Two weeks from now, Venus Express will train its camera back toward the Earth and Moon for another test activity, but the results are not expected to jaw-dropping.

"Given the distance, this will be more a calibration for one of the instruments rather than a real picture," Accomazzo said.

An exhaustive series of checks of the probe's scientific payload will also be carried out during the first few weeks of the mission, followed by a complete characterization of the thermal behavior of the craft in January and the main engine test in February before focus shifts to the fine navigation and other preparations in advance of the April 11 arrival at Venus.

In perhaps the most critical moment of the mission, the spacecraft's main engine will ignite for almost an hour to slow its tremendous speed to allow it to be captured by the Venusian gravity. The high stakes burn will drain more than 70 percent of the probe's nitrogen tetroxide and hydrazine-derived propellants, which account for over 1,200 pounds at liftoff, or almost half the weight of the entire spacecraft.


Venus Express will fire its main engine to enter orbit around the planet next April. Credit: ESA

Venus Express will initially be captured into a highly elliptical orbit that stretches from a low point of 155 miles to a high point of over 200,000 miles, and with an orbital period of approximately five-and-a-half Earth days. In the weeks after the arrival, the high point will be lowered to around 41,000 miles in altitude by an additional engine firing, and the orbit will take Venus Express nearly directly over the planet's poles with a period of about 24 hours.

Controllers will then put the craft's observation systems through yet another commissioning period before normal operations begin on July 4, 2006.

Aboard Venus Express, a science payload consisting of seven primary instruments from across Europe will begin their work to conduct comprehensive and unprecedented studies of the planet's atmosphere, which features surface air pressures over 90 times that of Earth's at sea level. This density, along with an abundance of carbon dioxide, helps induce a greenhouse effect that inflates temperatures to extreme levels that are higher than any other planet.

Venus Express will also learn more about the planet's surface and plasma environment as the atmosphere interacts with the solar wind. One objective of the mission is to look for possible volcanic activity at Venus, while another involves the study of fast-moving clouds.

"Some scientists believe there is the potential, at least, that life could be found in the clouds of Venus," said University of Colorado planetary scientist Larry Esposito, member of the Venus Express science team. "There has been speculation that sunlight absorbed by the clouds might be involved in some kind of biological activity."

"The spacecraft will be looking for 'hotspots' through the clouds in an attempt to make a positive detection of volcanoes," said Esposito. "While the Magellan mission that mapped Venus in the 1990s was not able to find evidence of volcanic activity, it did not close out the question. This will give us another shot."

Earlier missions had discovered evidence that a volcanic eruption had deposited large amounts of sulfur dioxide into the Venusian atmosphere, perhaps as recently as the late 1970's.


The Venus Express orbiter will examine the mysterious Venusian atmosphere and make new observations of the planet's surface. Credit: ESA

Though its present atmosphere is strikingly different from Earth's, Venus is otherwise often considered as Earth's twin planet. In its circuitous orbit around the Sun, Venus reaches distances from Earth closer than any other planet, and its size and mass are also very similar to Earth's.

But Venus rotates in the opposite direction of Earth, and a day on the planet equals around 243 Earth days. A year on Venus is about 225 Earth days.

The baseline mission for Venus Express lasts just two Venusian days, but that translates to roughly 500 Earth days. Options exist for officials to extend the life of the mission an additional two Venusian days should resources allow.

The first half of the primary mission will include the full observation of the planet, while the second half will be used to fill data voids from the first Venusian day, along with more detailed study of targets of interest. The craft's elliptical orbit allows it to gather both high-resolution and global observations on a wide scale throughout the mission.

Instruments involved in the science mission of Venus Express include:

• ASPERA The Analyzer of Space Plasma and Energetic Atoms seeks to study the interaction of the solar wind and the Venusian atmosphere. The instrument development was led by the Institute of Space Physics in Sweden.
  
• MAG From Austria, the Venus Express magnetometer will measure the magnetic field around the planet that originates from the interaction of the solar wind with the atmosphere.
  
• PFS The Planetary Fourier Spectrometer will gather precise data on vertical temperatures near the surface and in the upper atmosphere. The Italian instrument will also help determine the composition of the atmosphere and aid in the search for volcanic activity.
  
• SPCAV An imaging spectrometer from France and Russia for the Spectroscopy for Investigation of Characteristics of the Atmosphere of Venus, this instrument features ultraviolet, infrared, and solar occultation channels to look for traces of water vapor, molecular oxygen, and sulphur compounds.
  
• VeRa The German Venus Radio Science experiment will use the radio communications between Venus Express and Earth to conduct radio sounding of the planet's atmosphere, ionosphere, and the solar corona. Results can be used to determine density, temperatures, and pressure of the upper atmosphere.
  
• VIRTIS The Visible and Infrared Thermal Imaging Spectrometer features three observation channels to determine the composition of the lower atmosphere. The joint Italian-French instrument will also track clouds to study atmospheric dynamics.
  
• VMC The Venus Monitoring Camera will take images at visible, near-infrared, and ultraviolet wavelengths. The German camera will also take global images and study cloud dynamics.

Venus Express draws upon the heritage of Europe's earlier Mars Express and Rosetta missions, which lessened the time needed to develop the mission. Three of the craft's seven instruments are spares from the Mars Express project, while another two are from the Rosetta mission. Two more were developed specifically for Venus Express.

"The launch of Venus Express is a further illustration of Europe's determination to study the various bodies in our solar system," said David Southwood, Director of the European Space Agency's science programs. "We started in 2003 with the launch of Mars Express to the Red Planet and SMART-1 to the Moon and both these missions amply exceeded our expectations. Venus Express marks a further step forward, with a view to eventually rounding off our initial planetary overview with the BepiColombo mission to Mercury to be launched in 2013."

The $260 million mission was developed in less than three years from its approval in late 2002, but parts of the design had to be changed to allow operations on the much harsher space environment that will be encountered at Venus. The increased solar radiation forced engineers to add 27 layers of kapton insulation and reduce the size of the craft's solar panels responsible for electricity production. EADS Astrium led the manufacturing team of 25 subcontractors from 14 countries.


Venus Express is Europe's first mission to Earth's closest planetary neighbor. Credit: ESA

"With Venus Express, we fully intend to demonstrate yet again that studying the planets is of vital importance for life here on Earth," said Jean-Jacques Dordain, ESA's Director General. "To understand climate change on Earth and all the contributing factors, we cannot make do with solely observing our own planet. We need to decipher the mechanics of the planetary atmosphere in general terms."

"With Mars Express, we are studying the Martian atmosphere. With Huygens, we have explored that of Saturn's satellite Titan. And now with Venus Express, we are going to add a further specimen to our collection. Originally, Venus and Earth must have been very similar planets. So we really do need to understand why and how they eventually diverged to the point that one became a cradle for life while the other developed into a hostile environment."

Earlier probes to Venus have included missions from both the United States and the former Soviet Union which first flew by the planet at high speeds, while later missions orbited and even landed on Venus. Landers from the Soviet Venera series successfully touched down on the Venusian surface and returned images from 1975 through 1982. The U.S. Magellan mission completed a comprehensive radar mapping mission of Venus in the first half of the 1990's, and the most recent man-made visitor to the planet was in June 1999 when the Cassini spacecraft made a fleeting pass 370 miles above the surface.

[GioFX]

Immagini

ESA - Venus Express - Images


Video

Quicktime: http://a1862.g.akamai.net/7/1862/144...59K_Stream.mov

Windows Media:

http://a1862.g.akamai.net/7/1862/144...aunch_high.wmv

[duchetto]

Successful Venus Express main engine test

17 February 2006
One hundred days after beginning its cruise to Venus, ESA’s Venus Express spacecraft successfully tested its main engine for the first time in space.

The main engine test is a critical step in the mission. In fact, it is due to its powerful thrust that Venus Express will be able to ‘brake’ on arrival at Venus. The spacecraft must slow down in order to be captured in orbit around the planet.
The engine was fired during the night of 16/17 February, starting at 01:27 CET (00:27 UT) and the ‘burn’ lasted for about three seconds. Thanks to this engine burn, the spacecraft changed its velocity by almost three metres per second.

About one hour later, the data received from the spacecraft by the Venus Express ground control team (via ESA’s New Norcia antenna in Australia) revealed that the test was successful.

link

49 days till orbit insertion.

[GioFX]

Da SpaceFligthNow.com:

Spacecraft arrives at Venus to study planet's atmosphere

BY STEPHEN CLARK
SPACEFLIGHT NOW

Posted: April 11, 2006

Venus received a visitor from its sister planet this morning when a European space probe completed a five-month interplanetary cruise and swooped into orbit to begin the first comprehensive scientific survey of its sultry atmosphere.


Venus Express used its main engine to safely enter orbit around the planet. Credit: ESA

Venus Express - a $266 million mission conducted by the European Space Agency - became the first spacecraft to enter orbit around the planet since the 1990 arrival of NASA's Magellan radar observatory.

Officials at ESA's Space Operations Center in Germany received confirmation of the successful completion of a make-or-break 50-minute engine burn at around 0807 GMT (4:07 a.m. EDT). The burn actually ended several minutes before, but it took almost seven minutes for radio signals to make the one-way trip through the 78-million mile void between Earth and Venus.

Venus arrival operations began in earnest at 0603 GMT (2:03 a.m. EDT) Earth received time, when the craft began to maneuver to the precise orientation required for the orbital insertion engine firing. The process aligned the probe's main engine with the direction of travel. Telemetry from the S-band low gain antenna showed Venus Express in the proper position for the burn about a half-hour later.

A NASA Deep Space Network ground station in Madrid relayed data verifying the ignition of the powerful main engine at about 0717 GMT (3:17 a.m. EDT). During the critical burn, the spacecraft passed behind Venus and controllers lost the carrier signal from the probe for around ten minutes. As expected, after the communications link was restored, the propulsion system was shut off at 0807 GMT (4:07 a.m. EDT), followed by an announcement a few moments later.

After the burn, commands ordered the solar arrays to begin tracking the Sun, and one of the X-band high gain antennas was pointed back toward Earth to begin beaming back heaps of information on the orbiter's health and status shortly after 0900 GMT (5:00 a.m. EDT).

During the engine firing, most of the 1,254 pounds of propellant stored aboard Venus Express was exhausted, also significantly reducing the mass of the spacecraft. The burn slowed the velocity of Venus Express by 15 percent from the initial approach of 18,000 miles per hour. The decrease in relative speed allowed Venus' gravity to capture the craft in what was planned to be an egg-shaped orbit stretching from a low point of less than 250 miles above the surface to a high point of over 215,000 miles away. Each trip around the planet in such an orbit takes nine days.


Venus Express is Europe's first mission to Earth's closest planetary neighbor. Credit: ESA

There is a unique opportunity begin early scientific observations later this week. Because of the distance the spacecraft will reach from Venus in its initial capture orbit, instruments will be able to view the entire planet at once. Investigations into the solar wind's interaction with the planet are on tap, as well as continuous long-range studies of the atmosphere for over four days. Images of the entire planet will also be taken.

It will take almost a month for Venus Express to gradually reduce its altitude to the planned operational science orbit. A total of seven burns - two with the main engine and five with less powerful thrusters - will be required to arrive in the final 24-hour polar orbit with a low point of approximately 150 miles and a high point of 41,000 miles. Plans currently call for this orbit to be reached by around May 7.

A simultaneous checkout of the probe's seven science instruments begins on April 22 and lasts through much of May. By June 4, officials hope to begin the scientific operations phase that should last two Venusian days, or about 486 Earth days. Venus Express carries enough propellant to double the planned mission duration if ESA elects to do so.

Venus Express seeks to answer key questions left from earlier exploration of the hostile planet. Its instrument package will largely focus on the thick atmosphere of Venus, which holds secrets that still elude scientists.

The atmosphere acts as a greenhouse on the planet, sending surface temperatures soaring to almost 900 degrees Fahrenheit. Thick cloud layers race around the planet in just four days, and violent winds are common at all levels of the atmosphere. Venus Express aims to reveal some of the elusive secrets of the Venusian atmosphere by observing the structure, circulation, and composition of the atmosphere from the surface to high altitudes to help determine why the atmosphere behaves as it does.

Venus Express will also study how charged particles in the solar wind interact with Venus, and how materials in the atmosphere escape into space due to the planet's lack of a strong magnetic field. Other instruments will also investigate surface geological processes and search for volcanic activity. A wide-angle visible, near infrared, and ultraviolet camera is also expected to take thousands of detailed pictures during the mission.

"With the arrival of Venus Express, ESA is the only space agency to have science operations underway around four planets: Venus, the Moon, Mars, and Saturn," said David Southwood, director of ESA's science programs. "We are really proud to deliver such a capability to the international science community."

"By observing Venus and its complex atmospheric system, we will be able to better understand the mechanisms that steers the evolution of a large atmosphere and the change of climates," said Jean-Jacques Dordain, ESA Director General. "In the end, it will help us to get better models of what is actually going on in our own atmosphere, for the benefit of all Earth citizens."


The Venus Express orbiter will examine the mysterious Venusian atmosphere and make new observations of the planet's surface. Credit: ESA

Tuesday's crucial milestone completed a 153-day, 250 million mile journey from the Earth toward the inner solar system after the craft's launch last November 9 atop a Russian Soyuz rocket. The booster's Fregat upper stage placed Venus Express on a course to Venus about 90 minutes after liftoff. See Spaceflight Now's coverage of the launch here.

Preparations for the arrival at Venus included a full main engine test firing in mid-February to evaluate its performance before being called upon again. Controllers transitioned into the orbital insertion phase of the mission on April 4 when the low gain antenna's radio transmitter was turned on. High bandwidth communications are not possible with Venus Express during the engine burn because those antennas are pointed away from Earth.

The set of commands for the critical hours surrounding the burn early Tuesday were uplinked to Venus Express last Friday. The timeline was stored in an on-board computer before being executed with apparent perfection.

Developed in just three years and on a relatively inexpensive budget, Venus Express borrows much more than just its design from other ESA missions. A nearly identical twin to Mars Express currently in orbit around the Red Planet, Venus Express carries five instruments first manufactured as flight spares for both the Rosetta comet chaser and Mars Express.

Industrial teams led by Astrium of France constructed the spacecraft after finishing their work on Rosetta and Mars Express. The decision to use components and personnel left over from these missions helped to significantly reduce costs and development time on Venus Express.

[duchetto]

prime immagini della regione sud-polare

greyscale


false color


composita

[Paganetor]

incredibile!

meno male che la missione sta andando avanti come previsto... di sonde (costate centinaia di milioni di euro/dollari) se ne perdono pure troppe ormai

ma le ultime foto sono così a piena risoluzione (e mi sembra bassina come qualità ) o sono dei resize?

[gpc]

Originariamente inviato da Paganetor

incredibile!

meno male che la missione sta andando avanti come previsto... di sonde (costate centinaia di milioni di euro/dollari) se ne perdono pure troppe ormai

ma le ultime foto sono così a piena risoluzione (e mi sembra bassina come qualità ) o sono dei resize?

No, sono state prese molto più da lontano rispetto alla distanza a cui funzioneranno... sono solo i test della strumentazione.

[majin mixxi]

Originariamente inviato da CONFITEOR

sono ricchioni

bellissima

[Paganetor]

Originariamente inviato da gpc

No, sono state prese molto più da lontano rispetto alla distanza a cui funzioneranno... sono solo i test della strumentazione.

a ok, sono dei crop

bene, ottimo allora!

[GioFX]

Venus Express spacecraft has reached final orbit

EUROPEAN SPACE AGENCY NEWS RELEASE
Posted: May 9, 2006

Less than one month after insertion into orbit, and after sixteen loops around the planet Venus, ESA's Venus Express spacecraft has reached its final operational orbit on 7 May 2006.

Already at 21:49 CEST on 6th May, when the spacecraft communicated to Earth through ESA's ground station at New Norcia (Australia), the Venus Express ground control team at ESA's European Spacecraft Operations Centre (ESOC) in Darmstadt (Germany) received advanced confirmation that final orbit was to be successfully achieved about 18 hours later.

Launched on 9 November 2005, Venus Express arrived to destination on 11 April 2006, after a five-month interplanetary journey to the inner solar system. The initial orbit -- or 'capture orbit' -- was an ellipse ranging from 330,000 kilometres at its furthest point from Venus surface (apocentre) to less than 400 kilometres at its closest (pericentre).

As of the 9-day capture orbit, Venus Express had to perform a series of further manoeuvres to gradually reduce the apocentre and the pericentre altitudes over the planet. This was achieved by means of the spacecraft main engine -- which had to be fired twice during this period (on 20 and 23 April 2006) - and through the banks of Venus Express' thrusters -- ignited five times (on 15, 26 and 30 April, 3 and 6 May 2006).

"Firing at apocentre allows the spacecraft to control the altitude of the next pericentre, while firing at the pericentre controls the altitude of the following apocentre," says Andrea Accomazzo, Spacecraft Operations Manager at ESOC. "It is through this series of operations that we reached the final orbit last Sunday, about one orbital revolution after the last 'pericentre change manoeuvre' on Saturday 6 May".

Venus Express entered its target orbit at apocentre on 7 May 2006 at 15:31 (CEST), when the spacecraft was at 151 million kilometres from Earth. Now the spacecraft is running on an ellipse substantially closer to the planet than during the initial orbit. The orbit now ranges between 66,000 and 250 kilometres over the Venus and it is polar. The pericentre is located almost above the North pole (80 deg North latitude), and it takes 24 hours for the spacecraft to travel around the planet.

"This is the orbit designed to perform the best possible observations of Venus, given the scientific objectives of the mission. These include global observations of the Venusian atmosphere, of the surface characteristics and of the interaction of the planetary environment with the solar wind," says Hakan Svedhem, Venus Express Project Scientist. "It allows detailed high resolution observations near pericentre and the North Pole, and it lets us study the very little explored region around the South Pole for long durations at a medium scale," he concluded.

Until beginning of June, Venus Express will continue its "orbit commissioning Phase," started on 22 April this year.

"The spacecraft instruments are now being switched on one by one for detailed checking, which we will continue until mid May. Then we will operate them all together or in groups," said Don McCoy, Venus Express Project Manager. "This allows simultaneous observations of phenomena to be tested, to be ready when Venus Express' nominal science phase begins on 4 June 2006," he concluded.

[duchetto]

spulciando un po' sul forum di space.com ho trovato questo link
http://www.mentallandscape.com/V_DigitalImages.htm
non sapevo che i russi avevano in passato inviato diversi lander su venere..

[gpc]

Originariamente inviato da duchetto

spulciando un po' sul forum di space.com ho trovato questo link
http://www.mentallandscape.com/V_DigitalImages.htm
non sapevo che i russi avevano in passato inviato diversi lander su venere..

Oh sì, se non erro mantengono anche il record di funzionamento in quell'ambiente, diciamo così, ostile. Le sonde le facevano con le palle e contropalle, alla faccia dell'elettronica moderna... se pensi che quella roba lì andava a valvole...