Update at 06:00CET

This sent in about an hour ago by Andy Johnstone at ESOC.

Update at 05:00GMT

We are now transmitting from NASA’s 70m deep-space station in Madrid, DSS-63, and have released ESA’s 35m station at New Norcia.

The hand-over between the two networks was very smooth with both DSN [NASA] and ESTRACK [ESA] performing their duties exactly on time despite an unusually tight schedule and a hand-over method that is not routinely used.

The telemetry modulation was switched off again at 03:46GMT (04:46CET) and will remain off until shortly after we begin tracking with NASA’s 70m station at Goldstone, California, DSS-14, at 11:23GMT (12:32CET). Until then we will be relying on a system that the NASA tracking stationcolleagues have very helpfully provided for us, in which we can monitor directly their spectrum analysers and check on the quality of the signal.

Everything is currently running as planned and the next event will be the fly-by itself!

Saturday evening update from the MEX team

This sent in from Andy Johnstone at ESOC, ESA’s Space Operations Centre in Darmstadt, just a few minutes ago.

Everything is running smoothly at the moment! James Godfrey and I have been at ESOC since about 17:00GMT (18:00 local); I will stay on through the night and he will come back in with Erhard Rabenau at around 06:00GMT (07:00CET) on Sunday morning.

Acquisition of signal by ESA’s New Norcia ground tracking station was on time today at 18:19GMT (19:19 CET) via both X- and S-Band frequencies.

This animation shows the flyby on 29 Dec 2013 (speeded up) as if you were standing on Phobos, with Mars in the background and Mars Express sweeping out an arc above. Toward the end of the sequence, Mars Express disappears behind Mars and out of sight of Phobos. Thanks to the MEX team and Simon Wood at ESOC for generating this!

We have had our first period where we switch off the telemetry modulation [that is, downloading information from MEX] and only receive a carrier signal [just a raw radio signal] from the spacecraft.

Setting Mars Express to transmit carrier only increases the strength and quality of the signal, which therefore gives us better radio science, But this is always a worrying period for the Flight Control Team as we cannot tell what is happening on board the spacecraft. All we have to go on during these periods is a spectrum analyser and a display from the ground station saying that a signal is still being detected.

The next scheduled event will be loss of signal at 00:25GMT (01:25CET) when Mars Express passes behind Mars; it will reappear at the end of this occultation at 00:53GMT (01:53CET). This in itself is a good opportunity for radio science as our scientists can obtain information on Mars’ atmosphere by the way the radio signal is affected as it briefly passes through en route to Earth.

We are looking forward to a quiet night with everything running as planned!

Best regards

— Andy Johnstone
Spacecraft Operations Engineer, TT&C, Mars Express



First Contact! Mars Express’ first ‘conversation’ with Curiosity

As we reported yesterday, Mars Express had a busy Sunday evening, pointing first at NASA’s Curiosity rover on the surface of Mars and then swinging around to do another relay pass with Opportunity. We received the data from both of these passes this morning over ESA’s New Norcia ground station and, on first look, it seems that both relays were very successful.

First Laser-Zapped Rock on Mars

First Laser-Zapped Rock on Mars. This composite image, with magnified insets, depicts the first laser test by the Chemistry and Camera, or ChemCam, instrument aboard NASA’s Curiosity Mars rover. The composite incorporates a Navigation Camera image taken prior to the test, with insets taken by the camera in ChemCam. The circular insert highlights the rock before the laser test. The square inset is further magnified and processed to show the difference between images taken before and after the laser interrogation of the rock. The test took place on Aug. 19, 2012. Credit: NASA/JPL-Caltech/LANL/CNES/IRAP

In ESA’s MEX team, we’re particularly excited to have had our first contact with Curiosity – proof that the amazing new rover from the United States can talk with our veteran European Mars orbiter!

At the start of the contact, Mars Express was over 3600 km from Curiosity’s landing site in Gale Crater and closed in to only 1300 km by the end of the contact – streaking across the sky as seen from Curiosity.

During this overflight by Mars Express, it ‘hailed’ Curiosity in Gale Crater and the rover responded. The two spacecraft then autonomously established a link with each other and Curiosity flowed data back to Mars Express for nearly 15 minutes. This international chat between two spacecraft in deep space is proof of all our preparation, standardisation and cooperation work in action – so it’s something both agencies can be proud of.

ESA's first 35-metre deep-space ground station is situated at New Norcia, 140 kilometres north of Perth in Australia. The 630 tonne antenna will be used to track Rosetta and Mars Express, the latter to be launched in 2003, as well as other missions in deep space. The ground station was officially opened on 5 March 2003 by the Premier of Western Australia, Hon Dr Geoff Gallop. Credits: ESA

ESA’s first 35-metre deep-space ground station is situated at New Norcia, 140 kilometres north of Perth in Australia. The 630 tonne antenna will be used to track Rosetta and Mars Express, the latter to be launched in 2003, as well as other missions in deep space. The ground station was officially opened on 5 March 2003 by the Premier of Western Australia, Hon Dr Geoff Gallop.
Credits: ESA

The actual data that flowed back was made available to NASA earlier today, who will now retrieve and process the data.

Hopefully we’ll have some info from them in the next couple of days about what exactly was contained within. We’ll also receive (within Tuesday) the ‘housekeeping’ telemetry of Melacom – information on how our radio performed. This will allow us to double-check the performance of this first important contact with Curiosity.

The data was sent at a rate of only 8 kbps – 125 times slower than the 1-Mbit/second Internet connection you might have at home!

We wanted to take things easy to start with, though, and test the performance of the link. Nonetheless, we received 955 data packets from Curiosity, totalling 867 kilobytes of data.

This will be the first of several contacts with Curiosity in the future, as we better learn how to use and optimise this relay link between the two craft and the two space agencies. Watch this space for more details as we get them on this pass and the future contacts between Mars Express and Curiosity.


Mars Express rocking and rolling with NASA’s Curiosity & Opportunity

On 19 August, Sunday evening (European time), Mars Express will start its first data relay with NASA’s Mars Curiosity rover in style by fitting in not just our first pass with Curiosity but also by ‘rolling away’ afterwards to talk with NASA’s veteran Mars rover, Opportunity.

Still Life with Rover This full-resolution self-portrait shows the deck of NASA's Curiosity rover from the rover's Navigation camera. The back of the rover can be seen at the top left of the image, and two of the rover's right side wheels can be seen on the left. The undulating rim of Gale Crater forms the lighter color strip in the background. Bits of gravel, about 0.4 inches (1 centimeter) in size, are visible on the deck of the rover. Credit: NASA

Still Life with Rover This full-resolution self-portrait shows the deck of NASA’s Curiosity rover from the rover’s Navigation camera. The back of the rover can be seen at the top left of the image, and two of the rover’s right side wheels can be seen on the left. The undulating rim of Gale Crater forms the lighter color strip in the background. Bits of gravel, about 0.4 inches (1 centimeter) in size, are visible on the deck of the rover. Credit: NASA

This will be the first time in the history of the Mars Express mission where this double lander contact has been attempted within a single orbit of the spacecraft (1 orbit around Mars for Mars Express lasts around 7 hours).

As the spacecraft approaches the planet it will turn away from Earth and ‘roll’ over the top of Curiosity’s new home in Gale Crater, keeping the Melacom antennas pointed directly at the new rover.

After this contact, Mars Express will turn back to Earth briefly and then spin away again, performing the same ‘Spot Pointing’ manoeuvre for Opportunity as Mars Express flies over its location in Endeavour Crater. This double relay will be an exciting test of the capabilities of Mars Express, both in relay terms and in pointing, and to not only prove our communication capability with the new (and fantastic!) Curiosity rover but also to continue our commitment to its predecessor – the venerable Opportunity rover.

A Digital Opportunity Rover on Mars Credit: Mars Exploration Rover Mission, Cornell, JPL, NASA Rover Model: D. Maas - Synthetic Image: Z. Gorjian, K. Kuramura, M. Stetson, E. De Jong.

A Digital Opportunity Rover on Mars Credit: Mars Exploration Rover Mission, Cornell, JPL, NASA Rover Model: D. Maas – Synthetic Image: Z. Gorjian, K. Kuramura, M. Stetson, E. De Jong. Via http://apod.nasa.gov/apod/ap051214.html

The past weeks have seen intense cooperation between NASA and ESA to coordinate and plan these activities, which are intended as demonstrations of the relay capabilities of Mars Express. The overflight of Opportunity will be part of a long-standing activity to periodically check the ability of Mars Express to relay data from Opportunity, if ever needed.

Many of these overflights were done leading up to the landing of Curiosity to cement the technical ability of the two agencies to work together on planning routine relay operations. The overflight of Curiosity will be the first time that Mars Express and Curiosity have actually ‘talked’ to each other.

During the landing of Curiosity, Mars Express only listened in and recording the radio signal of Curiosity, but Sunday evening, 19 August, the two spacecraft will actually have a ‘conversation’ and for the first time Mars Express will receive and decode actual data from the lander.

We’re confident in the ability of the two spacecraft to be able to communicate for several reasons – the main one being that both implement an international standard called Proximity-1 [this is mentioned in our earlier Melacom post – Ed].

This standard was designed to make sure that even though the spacecraft come from different manufacturers and different agencies, the way they talk to each other is still the same – it can be thought of like an ‘agreed common language’.

On top of this, is our extensive experience relaying data for Phoenix, Spirit and Opportunity and the fact that a team from QinetiQ (who built our Melacom radio) travelled to JPL to test a copy of it with a copy of the Curiosity radio. However, any new activity in space is challenging and we stand ready at ESOC to investigate, analyse and improve – optimising our ability to support the Curiosity mission for NASA.

All of this will allow Mars Express to make a call to Curiosity in Gale Crater and between the spacecraft agree autonomously to exchange data. Curiosity will send back data that will be decoded by Mars Express and stored ready for forwarding to Earth; then we’ll quickly reset and prepare a very similar activity for Opportunity in Endeavour Crater.

Next, on Monday morning, Mars Express will send the data to ESA’s 35m New Norcia (Australia) ground station and then from there it will make its way to ESOC and on to the control room at JPL.

The data’s journey will be long (Gale Crater/Endeavour Crater -> Mars Express -> New Norcia, Australia -> ESOC, Germany -> JPL, USA) but we’ll make sure it arrives safe and sound – proving the ability of Mars Express to support communications with both Curiosity and Opportunity whenever needed.

We’ll post more details when we know the results of the test and can hopefully announce on Monday that Mars Express has been ‘qualified’ as a really-long-distance relay for Curiosity – expanding the network of spacecraft and cooperation at Mars in spectacular style!

Nice note from NASAs’ MSL Mission Interface Manager

Curiosity rover descending under parachute to martian surface, as seen by NASA Odyssey Credit: NASA/JPL-Caltech/Univ. of Arizona

PASADENA, Calif. – An image from the High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance orbiter captured the Curiosity rover still connected to its almost 16-meter-wide parachute as it descended toward Gale Crater.

This note came in last night from Susan Kurtik, NASA’s MSL Mission Interface Manager at JPL and the person with whom ESA’s ESTRACK team at ESOC worked to plan and conduct the tracking of MSL’s arrival using New Norcia station (see our earlier post – ESA, NASA, Parkes: Big ears on Earth will listen to MSL descend – Ed.)

Susan wrote:


We want to extend our Congratulations for the incredible success of the ESA MEX and ESTRACK support of the MSL EDL!  It was flawless and exceeded everyone’s expectations – great job!

Following the landing, the MSL mission manager came over to personally thank us and asked that we extend his most sincere and deep appreciation for the outstanding support of the DSN and ESA teams.  It is always an honor to be collaborating with our international partners and to be working together with such a dedicated and highly skilled team.  We have changed the world today, together.  And we have demonstrated once again the tremendous benefits of international collaboration!

Sending ENORMOUS THANKS to our ESA partners!

Best regards,

Susan C. Kurtik
Jet Propulsion Laboratory
Deep Space Network
MSL Mission Interface Manager

What is Open Loop Recording?

How Mars Express will listen to Curiosity

3-D waterfall diagram showing the open loop recording made by Mars Express of MER-B (Opportunity) during the rehearsal overflight for Curiosity EDL.

You’ll see a lot on our coverage of the Curiosity landing about Open Loop Recording,’ something which was hinted at in a previous post about the difference between ‘signal’ and ‘data’.

OLR refers to the type of recording that will be made by Mars Express as Curiosity descends towards Mars, and in parallel by ESA’s New Norcia station here on Earth.

In open loop recording, we don’t try to decode the bits and bytes being sent by the descending lander but instead try and listen to as much of the radio spectrum as we can, hopefully detecting the tone of the lander’s transmissions within this spectrum. Think of it like listening to a crowd of people – you can either focus on the words one person is saying, or listen to the whole crowd to get a full picture of what’s going on; that’s what we’ll do with open loop recording.

On Mars Express we’ll use our UHF Melacom radio to listen in on the UHF part of the spectrum – usually used on Earth for radio and television transmissions; it’s also used at Mars as the frequency that different orbiters and landers use to talk to each other.

From New Norcia we’ll be listening to the X-Band part of the spectrum – used on Earth mainly for radar systems but also as a way of communicating with spacecraft across the solar system (Mars Express uses X-Band for its main link back to Earth).

Each of these parts of the spectrum is actually a wide range of frequencies and in open loop we listen to as many as possible, creating a diagram like the one in the picture above.

Continue reading

Commands away!

Mars Express has now been almost fully prepared for the upcoming arrival of MSL! This week’s Spacecraft Operations Coordinator, James Godfrey, has confirmed that all the commands to Mars Express for the MSL tracking activities have been transmitted to Mars.

Two clicks (and a lot of background work!) was all it took to start the command file transmission to Mars Express. At 11:04 CEST our Spacecraft Controller at ESOC hit the ARM button then the GO button and the commands began their journey to Mars. Take a look at the video above to see the commands flying off our control system.

From the control system at ESOC they were sent around the world to our deep space antenna at New Norcia, Australia, and from there they were modulated onto a radio signal and blasted with 10 kilowatts (that’s like 10,000 mobile phones all calling at once!) from the antenna toward Mars.

Their journey of 245,750,000 km took 13 minutes and 39 seconds. Once they arrived, Mars Express turned the radio signal back into bits and bytes and stored it on the spacecraft.

The whole command file contained all the instructions for Mars Express to follow over the next week of operations, including the critical instructions to the spacecraft to perform ESA’s support of the MSL landing with Mars Express. These commands will wait on the spacecraft’s on-board memory (its ‘hard drive’) and then execute automatically according to the schedule we created here on Earth.

Mars Express – timeline for MSL support

Early on 6 August, Mars Express will receive crucial signals from NASA’s Mars Science Laboratory mission as it delivers the car-sized Curiosity rover onto the Red Planet. The ESA spacecraft will begin tracking the NASA mission 45 minutes before it enters the martian atmosphere; an ESA ground station will also record vital signals.

The highlight of ESA’s support for NASA’s Curiosity landing happens at 06:29 on Monday, 6 August, when the Mars Express Lander Communication (MELACOM) system is switched on. Recording of the radio signals transmitted by the Mars Science Laboratory (MSL) is planned to begin at 07:09 and end at 07:37 (all times shown as ground event time in CEST).

ESA’s ground tracking station in New Norcia, Australia, will also listen and record signals from the NASA mission at the same time.

CEST = UTC + 2 hours
Earth time = Mars time + 13min:48sec
MEX: Mars Express
MSL: Mars Science Laboratory
NNO: ESA New Norcia station
AOS: Acquisition of signal
S/C: Spacecraft
All times subject to change

Event Earth CEST Earth UTC S/C UTC Notes
DSS-15 (G/S) AOS 4:03:00 2:03:00
NNO AOS MEX 4:03:00 2:03:00
NNO AOS MSL 4:05:00 2:05:00
DSS-15 LOS MEX 6:05:00 4:05:00
NNO LOS MEX 6:05:00 4:05:00
NNO start recording MSL signals 6:25:00 4:25:00
MEX starts slew to point at MSL 6:06:30 4:06:30 3:52:42
MEX MELACOM reciever ON 6:28:48 4:28:48 4:15:00
MEX ends slew to point at MSL 6:36:38 4:36:38 4:22:50 Now pointing at MSL
MEX starts recording MSL signals 7:08:48 5:08:48 4:55:00
MSL Cruise Stage separation 7:14:34 5:14:34 5:00:46 MSL starts transmitting
MRO UHF TM capture starts 7:21:34 5:21:34 5:07:46
MSL Atmosphere entry 7:24:34 5:24:34 5:10:46
MSL Start plasma attenuation 7:26:13 5:26:13 5:12:25
ODY UHF bent pipe relay start 7:26:34 5:26:34 5:12:46
MSL End plasma attenuation 7:27:13 5:27:13 5:13:25
MSL Parachute deploys 7:28:46 5:28:46 5:14:58
MSL Heat shield separation 7:29:07 5:29:07 5:15:19
MSL Backshell separation 7:30:40 5:30:40 5:16:52
MSL Curiosity separation 7:31:17 5:31:17 5:17:29
Curiosity touchdown 7:31:37 5:31:37 5:17:49 Planned
MEX MELACOM reciever OFF 7:36:48 5:36:48 5:23:00
ODY UHF bent pipe relay end 7:37:37 5:37:37 5:23:49
MEX starts slew to point at Earth 7:38:58 5:38:58 5:25:10
NNO stop recording MSL signals 7:40:00 5:40:00
MEX ends slew to point at Earth 8:09:46 6:09:46 5:55:58 Now pointing at Earth
MEX transmitter ON 8:09:48 6:09:48 5:56:00
MEX start sending TM 8:15:00 6:15:00 6:01:12
MEX start recording download 8:15:31 6:15:31 6:01:43
MEX stop recording download 8:40:31 6:40:31 6:26:43
ESOC team passes data to NASA 8:42:00 6:42:00

NASA MSL mission communicates with ESA station


This just in from Wolfgang Hell, one of our ESTRACK engineers looking after the ESA station support to MSL. ESA’s 35m New Norcia (NNO) station made contact with MSL earlier this afternoon — and the connection went fine! Wolfgang wrote:

We had a fully nominal MSL pass over NNO and NASA JPL reports that the telemetry obtained via the first communication chain at NNO was error free. I expect reports for data receipt from chains 2 and 3 during the upcoming telecon.


ESA’s New Norcia station elevating for tracking pass

Next Monday, around 12:00 local, this is how ESA’s superb (may we also say beautiful?) 35m deep-space tracking station at New Norcia, Australia, will appear as it swings into position to track Mars Express and listen for NASA’s Mars Science Lab.

Clip recorded in April 2012 showing ESA’s 35m deep-space tracking station at New Norcia, Australia, swinging into action to conduct a communication pass. DSA-1 is designed for deep-space satellite missions and provides daily support to Mars Express, Rosetta and Venus Express for routine operations. The mechanical movable structure weighs 580 tonnes. Engineers can point it with a speed of 0.4 degrees per second in both axes (horizontal and vertical). Its Servo Control System provides the highest possible pointing accuracy under the site’s environmental, wind and temperature conditions. More details via http://bit.ly/96u55A