Editing Mars Express (section)

== Mission profile ==
{{more citations needed section|date=June 2011}}

=== Mission preparation ===
In the years preceding the launch of a spacecraft numerous teams of experts distributed over the contributing companies and organisations prepared the space and ground segments. Each of these teams focussed on the area of its responsibility and interfacing as required. A major additional requirement raised for the Launch and Early Orbit Phase (LEOP) and all critical operational phases was that it was not enough merely to interface; the teams had to be integrated into one Mission Control Team. All the different experts had to work together in an operational environment and the interaction and interfaces between all elements of the system (software, hardware and human) had to run smoothly for this to happen:

* the flight operations procedures had to be written and validated down to the smallest detail;
* the [[control system]] had to be validated;
* system Validation Tests (SVTs) with the satellite had to be performed to demonstrate the correct interfacing of the ground and space segments;
* mission Readiness Test with the [[Ground station|Ground Stations]] had to be performed;
* a Simulations Campaign was run.

=== Launch ===
[[File:Animation of Mars Express trajectory around Sun.gif|thumb|Animation of Mars Express's trajectory around Sun<br />{{legend2|magenta|Mars Express}}{{·}}{{legend2|Yellow|Sun}}{{·}}{{legend2|Royalblue|Earth}} {{·}}{{legend2|Lime|Mars}}]]
The spacecraft was launched on June 2, 2003, at 23:45 local time (17:45 UT, 1:45&nbsp;p.m. EDT) from [[Baikonur Cosmodrome]] in [[Kazakhstan]], using a [[Soyuz-FG]]/[[Fregat]] rocket. The ''Mars Express'' and Fregat booster were initially put into a 200&nbsp;km Earth [[parking orbit]], then the Fregat was fired again at 19:14 UT to put the spacecraft into a Mars transfer orbit. The Fregat and ''Mars Express'' separated at approximately 19:17 UT. The [[solar panel]]s were then deployed and a trajectory correction manoeuvre was performed on June 4 to aim ''Mars Express'' towards Mars and allow the Fregat booster to coast into interplanetary space. The ''Mars Express'' was the first Russian-launched probe to successfully make it out of low Earth orbit since the Soviet Union fell.

=== Near Earth commissioning phase ===
The Near Earth commissioning phase extended from the separation of the spacecraft from the launcher upper stage until the completion of the initial check out of the orbiter and payload. It included the solar array deployment, the initial attitude acquisition, the declamping of the Beagle-2 spin-up mechanism, the injection error correction manoeuvre and the first commissioning of the spacecraft and payload (final commissioning of payload took place after Mars Orbit Insertion). The payload was checked out one instrument at a time. This phase lasted about one month.

=== The interplanetary cruise phase ===
This five month phase lasted from the end of the Near Earth Commissioning phase until one month prior to the Mars capture manoeuvre and included trajectory correction manoeuvres and payloads calibration. The payload was mostly switched off during the cruise phase, with the exception of some intermediate check-outs. Although it was originally meant to be a "quiet cruise" phase, It soon became obvious that this "cruise" would be indeed very busy. There were [[star tracker]] problems, a power wiring problem, extra manoeuvres, and on October 28, the spacecraft was hit by one of the largest [[solar flare]]s ever recorded.
=== Lander jettison ===
The [[Beagle 2]] lander was released on December 19, 2003, at 8:31 UTC (9:31 CET) on a [[Ballistics|ballistic]] cruise towards the surface. It entered Mars' atmosphere on the morning of December 25. Landing was expected to occur at about 02:45 UT on December 25 (9:45&nbsp;p.m. EST December 24). However, after repeated attempts to contact the lander failed using the ''Mars Express'' craft and the [[NASA]] ''[[Mars Odyssey]]'' orbiter, it was declared lost on February 6, 2004, by the Beagle 2 management board. An inquiry was held and its findings were published later that year.<ref name="inquiry" />

=== Orbit insertion ===
[[File:Animation of Mars Express trajectory around Mars.gif |thumb |right |Animation of ''Mars Express''{{'s}} trajectory around [[Mars]] from December 25, 2003, to January 1, 2010<br />{{legend2|magenta| Mars Express}}{{·}}{{legend2| Lime|[[Mars]]}}]]''Mars Express'' arrived at Mars after a 400 million km journey and course corrections in September and in December 2003.

On December 20 ''Mars Express'' fired a short thruster burst to put it into position to orbit the planet. The ''Mars Express'' orbiter then fired its main engine and went into a highly elliptical initial-capture orbit of 250&nbsp;km × 150,000&nbsp;km with an inclination of 25 degrees on December 25 at 03:00 UT (10:00&nbsp;p.m., December 24 EST).

First evaluation of the orbital insertion showed that the orbiter had reached its first milestone at Mars. The orbit was later adjusted by four more main engine firings to the desired 259&nbsp;km × 11,560&nbsp;km near-polar (86 degree inclination) orbit with a period of 7.5 hours. Near [[periapsis]] (nearest to Mars) the top deck is pointed down towards the Martian surface and near [[apoapsis]] (farthest from Mars in its orbit) the high gain antenna will be pointed towards Earth for uplink and downlink.

After 100 days the apoapsis was lowered to 10,107&nbsp;km and periapsis raised to 298&nbsp;km to give an orbital period of 6.7 hours.

The [[MARSIS]] radar booms were originally scheduled to be deployed in April 2004, but this was delayed to 2005 out of fear that the deployment could damage the spacecraft through a whiplash effect.<ref name=":2" />[[File:Mars Express illustration highlighting MARSIS antenna.jpg|thumb|Illustration of ''Mars Express'' with [[MARSIS]] antenna deployed]]{{multiple image
| align             = right
| direction         = vertical
| image1            = PIA07944 Mars Express Seen by Mars Global Surveyor.jpg
| caption1          = Image of ''Mars Express'' in orbit, taken by [[Mars Global Surveyor]]
| image2            = PIA07944 Mars Express Seen by Mars Global Surveyor, Figure 1.jpg
| caption2          = Artist's impression of the expected appearance of ''Mars Express'' at the time of the Mars Global Surveyor image
| total_width       = 250
}}

=== Routine phase: science return ===
Since orbit insertion ''Mars Express'' has been progressively fulfilling its original scientific goals. Nominal science observations began during July 2005. Nominally the spacecraft points to Mars while acquiring science and then slews to Earth-pointing to downlink the data, although some instruments like [[MARSIS]] or Radio Science might be operated while spacecraft is Earth-pointing.