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Unmanned Spaceflight.com > Mars & Missions > Past and Future > ExoMars Program
Habukaz
The latest and greatest on the plans for the CaSSIS imaging instrument:

QUOTE
After ExoMars TGO has reached its Mars Capture Orbit, the intention is to switch on CaSSIS in the week from November 21 to 28 and acquire images of Mars for the first time. A media release is planned on 1 December 2016 when ESA’s Ministerial Council is being held in Lucerne.

[...]

The highly elliptical orbit is not ideal. When we approach Mars, the orbital speed is much higher than in our science orbit and the timing will be difficult to get right. Our aim is to get something – we do our best – and learn from what we get.

[...]

When should the image be acquired, do we have enough time to rotate the instrument to get the 2nd half of a stereo pair, do we have enough time to get the data out of the instrument before the next image should be acquired? That planning process costs a lot of time and we don’t have many people to help do it. The hard part in MCO is that the speed over the surface at periapsis is much quicker than in the circular orbit so there is a good chance to mess it up.


http://nccr-planets.ch/getting-ready-tricky-task/
Habukaz
First images should be from the Noctis Labyrinthus region (western edge of Valles Marineris) and (ideally) form a stereo observation.

QUOTE
There are no specific imaging targets in mind, although near the closest approach of the first orbit the orbiter will be flying over the Noctis Labyrinthus region and it will attempt to obtain a stereo pair. In the second orbit, it has the opportunity to capture images of Phobos.


http://www.esa.int/Our_Activities/Space_Sc...r_first_science

Some details on what the other instruments will be doing in the link.
mcaplinger
First images: http://www.esa.int/Our_Activities/Space_Sc...A_s_new_orbiter
Habukaz
Aerobraking complete

Instrument testing starts mid-March, routine science observations around 21 April.

QUOTE
The initial phases of science gathering, in mid-March, will be devoted to checking out the instruments and conducting preliminary observations for calibration and validation. The start of routine science observations should happen around 21 April.

“Then, the craft will be reoriented to keep its camera pointing downwards and its spectrometers towards the Sun, so as to observe the Mars atmosphere, and we can finally begin the long-awaited science phase of the mission,” says Håkan Svedhem, ESA’s project scientist.
PaulH51
QUOTE (Habukaz @ Feb 21 2018, 06:31 PM) *
Aerobraking complete

Instrument testing starts mid-March, routine science observations around 21 April.

TGO returns its first images from its new orbit: http://www.esa.int/Our_Activities/Space_Sc..._from_new_orbit
antipode
Wow! If that's anything like what we will see in future i cant wait.

P
wildespace
QUOTE (PaulH51 @ Apr 26 2018, 09:25 PM) *
TGO returns its first images from its new orbit: http://www.esa.int/Our_Activities/Space_Sc..._from_new_orbit

Any information on what filters were used for this image? It looks similar to MRO's IRB images (with telltale blues and yellows).

Is there a HiRISE coverage of this area?

P.S. If the image is indeed IRB, here's my attempt at reshuffling colour channels to imitate RGB:

http://ibb.co/d3r1tn

Click to view attachment

I assigned the green channel to red, blue to blue, and the average between the two to green, with some hue balancing to move the resulting orange and cyan to red and blue respectively.
Phil Stooke
Need a TGO-CASSIS image fix? There are 5 here:

http://www.esa.int/Our_Activities/Space_Sc...cards_from_Mars

Phil
bobik
Welcome to Cassis DTM Repository
bobik
At the Tenth Moscow Solar System Symposium project scientist Håkan Svedhem revealed that CaSSIS had run into problems with its rotation mechanism. Higher than normal friction in the bearing had led to a suspension of its operation with tests of a new rotation method are going to begin in mid-October. No direct indication in the talk if there are any lasting implications on the stereo imaging capability of the camera.
Sean
QUOTE (bobik @ Sep 13 2019, 10:28 AM) *


Everything except one item is locked until April 2020.
bobik
During the last MEPAG meeting it was said that there has been a recent malfunction of the ACS TIRVIM channel on ExoMars TGO. The cryocooler is no longer able to bring the "IR detector to working temperature". There is no detailed treatment in the presentation materials what this actually means for the further operation of the TIRVIM channel in particular or the science operations in general; besides, that it was mainly used for a general characterization of the martian atmosphere, nor possible root causes of the technical problem are mentioned (A dedicated press release would be desirable). The initial TIRVIM design had two cooled detectors and one redundant pyroelectric detector working at ambient temperature. Because of mass constraints, the design was changed, one of the two cooled detectors and the redundant pyroelectric detector had to be cancelled. That is unfortunate, indeed. The cryocooler is a RICOR K508 Stirling cycle cryogenic refrigerator adapted for operation in space, similar cryocoolers were also used in the ACS MIR channel and NOMAD instrument on ExoMars TGO, as well as highly successfully in many other current and past interplanetary projects.
bobik
It is noticeable that new entries into the Cassis DTM Repository became very sporadic over the last year. If this is related to the problems with the CaSSIS rotation mechanism is impossible to say without any "official" acknowledgment of the problem, let alone its solution.
MahFL
New gas found in Mars's atmosphere.

https://www.esa.int/Science_Exploration/Hum...er_loss_on_Mars
bobik
An intriguing explanation why so few CaSSIS stereo pairs are made (#13), not rotation mechanism bearing problems (#10) but rather the stereo-mode is relatively power-intensive, thus only used sparingly in order to save the batteries... True or not, this issue apparently did not exist before mid-March 2019. huh.gif
bobik
A recent paper (full text available) on CaSSIS science planning contains some info about the rotation mechanism problems (#10) and especially about the consequences for science operations:

QUOTE
Another important event that triggered software changes at all levels were the motor issues CaSSIS experienced at the start of 2019. Although CaSSIS did recover part of the motor movement, at the time of writing the first 100 degrees of the full 360° rotation are not being used. Also the motor is being moved less frequently, with the end result that more images are acquired with a fixed motor position. In order to minimize the impact on the science, the tools were updated to take into account this fixed motor position. The CaSSIS team then identifies on a weekly basis a motor position that allows acquisition of many targets with a maximum of 20° misalignment with the spacecraft ground track. This provides almost full overlap of the colours in the CaSSIS focal plane so that colour imaging is efficient.

The tools were also updated to allow for stereo images and aligned single images that use the motor on an individual basis. As the CaSSIS teams has gained confidence the number of images allowed with these methods has been slowly increased to the point that is almost indistinguishable from the operations before the motor issues.
volcanopele
Yep, we are taking 5 stereo images per week to help reduce wear and tear on the motor mechanism. We are also taking up to 30 "aligned" images, where the motor is rotated to align with the image groundtrack. Otherwise a fixed motor position is used.
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