Andrew Yee[_1_]
May 22nd 08, 05:54 PM
ESA News
http://www.esa.int
22 May 2008
Timeline: Mars Express support to Phoenix landing
Beginning late on 25 May, Mars Express will execute a series of
pre-programmed commands specially designed to support NASA's Phoenix lander.
The ESA spacecraft will conduct a high-speed slew, enabling it to track
Phoenix as it enters the martian atmosphere.
Mars Express will point its Lander Communications Antenna toward Phoenix's
planned entry trajectory and record signals transmitted from the lander as
it plunges toward the surface during the critical entry, descent and landing
(EDL) phase.
Support for Phoenix starts at 21:00 CEST [1900 UTC] when the spacecraft's
MELACOM (Mars Express Lander Communications) system is switched on.
Recording of radio signals transmitted by Phoenix will begin at 01:21 CEST,
26 May [2321 UTC May 25] and end at 01:47 CEST, 26 May [2347 UTC May 25].
During the recording, Mars Express will conduct a high-speed slew as MELACOM
tracks Phoenix, keeping Phoenix in the line of sight of the MELACOM antenna.
Upon completion of recording, Mars Express will perform a (normal) slew to
Earth pointing attitude, and at 02:25 CEST [0025 UTC] on 26 May, the
spacecraft will begin transmitting the recorded data, via a NASA deep-space
ground station, to ESA's Space Operations Centre (ESOC), Darmstadt, Germany.
The one-way signal travel time will be 15 minutes and 20 seconds. The
download will be complete by 02:57 CEST [0057 UTC], and ESOC will make the
data available to NASA immediately upon receipt.
Mars Express will subsequently download the recorded data two more times to
ensure redundancy. The ESA spacecraft will additionally monitor signals from
Phoenix during an overflight of the landing zone, 08:12-08:23 CEST
[0612-0623 UTC], and 14 more times during the following week. During the
night of 25/26 May, Mars Express will be controlled by the Flight Control
Team working in the Dedicated Control Room at ESOC.
Observations before and during Phoenix descent
It is planned that two Mars Express instruments, the High Resolution Stereo
Camera (HRSC) and the Ultraviolet and Infrared Atmospheric Spectrometer
(SPICAM), will be turned on for observations during the Phoenix EDL.
The observations are aimed at visually capturing the trail of the lander's
trajectory to the Martian surface, studying the characteristics of the
atmosphere during the lander's descent, and monitoring the lander's
performance during EDL.
It is not possible to know the exact route Phoenix will take when descending
to the surface, and so it is possible that the instruments may not be
looking in the correct direction during the event. This makes the likelihood
of success less than certain.
Nonetheless, and despite the technical and physical challenges, the Mars
Express science teams are doing their best to boost the potential scientific
value of the observations. In any event, highest priority will be given to
tracking the lander using MELACOM.
These challenging scientific observations have never been performed at Mars
before, and if successful, the knowledge gained will be useful for future
missions.
In addition to the observations planned during EDL, the Planetary Fourier
Spectrometer (PFS) on board Mars Express has been collecting relevant data
since 8 May this year. This includes information on the physical conditions
of the Martian atmosphere (temperature, pressure and density) above the
expected the landing site. This data is being provided to NASA in support of
their observations of the physical conditions in the atmosphere prior to
landing.
Timeline:
http://www.esa.int/esaSC/SEM3ZB1YUFF_index_0.html
http://www.esa.int
22 May 2008
Timeline: Mars Express support to Phoenix landing
Beginning late on 25 May, Mars Express will execute a series of
pre-programmed commands specially designed to support NASA's Phoenix lander.
The ESA spacecraft will conduct a high-speed slew, enabling it to track
Phoenix as it enters the martian atmosphere.
Mars Express will point its Lander Communications Antenna toward Phoenix's
planned entry trajectory and record signals transmitted from the lander as
it plunges toward the surface during the critical entry, descent and landing
(EDL) phase.
Support for Phoenix starts at 21:00 CEST [1900 UTC] when the spacecraft's
MELACOM (Mars Express Lander Communications) system is switched on.
Recording of radio signals transmitted by Phoenix will begin at 01:21 CEST,
26 May [2321 UTC May 25] and end at 01:47 CEST, 26 May [2347 UTC May 25].
During the recording, Mars Express will conduct a high-speed slew as MELACOM
tracks Phoenix, keeping Phoenix in the line of sight of the MELACOM antenna.
Upon completion of recording, Mars Express will perform a (normal) slew to
Earth pointing attitude, and at 02:25 CEST [0025 UTC] on 26 May, the
spacecraft will begin transmitting the recorded data, via a NASA deep-space
ground station, to ESA's Space Operations Centre (ESOC), Darmstadt, Germany.
The one-way signal travel time will be 15 minutes and 20 seconds. The
download will be complete by 02:57 CEST [0057 UTC], and ESOC will make the
data available to NASA immediately upon receipt.
Mars Express will subsequently download the recorded data two more times to
ensure redundancy. The ESA spacecraft will additionally monitor signals from
Phoenix during an overflight of the landing zone, 08:12-08:23 CEST
[0612-0623 UTC], and 14 more times during the following week. During the
night of 25/26 May, Mars Express will be controlled by the Flight Control
Team working in the Dedicated Control Room at ESOC.
Observations before and during Phoenix descent
It is planned that two Mars Express instruments, the High Resolution Stereo
Camera (HRSC) and the Ultraviolet and Infrared Atmospheric Spectrometer
(SPICAM), will be turned on for observations during the Phoenix EDL.
The observations are aimed at visually capturing the trail of the lander's
trajectory to the Martian surface, studying the characteristics of the
atmosphere during the lander's descent, and monitoring the lander's
performance during EDL.
It is not possible to know the exact route Phoenix will take when descending
to the surface, and so it is possible that the instruments may not be
looking in the correct direction during the event. This makes the likelihood
of success less than certain.
Nonetheless, and despite the technical and physical challenges, the Mars
Express science teams are doing their best to boost the potential scientific
value of the observations. In any event, highest priority will be given to
tracking the lander using MELACOM.
These challenging scientific observations have never been performed at Mars
before, and if successful, the knowledge gained will be useful for future
missions.
In addition to the observations planned during EDL, the Planetary Fourier
Spectrometer (PFS) on board Mars Express has been collecting relevant data
since 8 May this year. This includes information on the physical conditions
of the Martian atmosphere (temperature, pressure and density) above the
expected the landing site. This data is being provided to NASA in support of
their observations of the physical conditions in the atmosphere prior to
landing.
Timeline:
http://www.esa.int/esaSC/SEM3ZB1YUFF_index_0.html