Universe Today

Image credit: ESA

Unlike its missing passenger, Beagle 2, controllers from the European Space Agency know exactly where Mars Express is – exactly where they want it. The spacecraft is currently on a wide equatorial orbit which brings it as close as 400 km and then out to 188,000 km away from the planet. Engineers are preparing the spacecraft for a further burn of its main engine which will bring the spacecraft into a closer polar orbit around Mars. Once Mars Express modifies its orbit, it will be the best candidate to communicate with the missing Beagle 2; starting January 4, 2004.

The Mars Express orbiter, mothership of Europe’s first mission to the Red Planet, is in a stable and precise orbit around Mars.

The essential Mars Orbit Insertion (MOI) manoeuvre had been completed on 25 December at 3:47 CET. This brought the spacecraft as close as 400 kilometres to the surface of Mars.

Afterwards, the spacecraft went into a highly elliptical orbit, going as far as 188 000 kilometres away from the planet. The most essential part of the Mars Express mission is performing very well and we are expecting exciting science from January 2004 onwards.

Today, 27 December, the mission control team at ESOC prepared the next steps to turn Mars Express from a near-equatorial orbit into a polar orbit. Michael McKay, Mars Express Flight Director explained, “Our flight dynamics and flight operations teams thoroughly discuss, evaluate and prepare the commands to perform a series of manoeuvres starting with a major move on 30 December – where we will fire the main engine again for three minutes.

“These key manoeuvres will allow us to get even closer to Mars. They will not only allow us more frequent ‘overflights’ of the Beagle 2 landing area, but also ensure the beginning of the orbiter’s science mission. As Mars Express is the planned main communication partner of the Beagle 2, the chances of obtaining a signal strongly increase with these manoeuvres after 4 January 2004.”

Close European and international co-operation
The ESA control team at ESOC are in regular contact with their colleagues of the Beagle 2 team and the Jodrell Bank telescope in the UK, with NASA ground stations and with several other European partners (UK, Germany, Netherlands, etc.). Many international offers have been forthcoming to support the search for the Beagle 2 lander.

Original Source: ESA News Release

Image credit: ESA

Controllers have made two more attempts to reach the Beagle 2 lander, which was thought to have entered Mars’ atmosphere on December 25: once with both the Jodrell Bank radio telescope and again with Mars Odyssey. Although they’re disappointed, the engineers still have a few tricks up their sleeves. A special team has been put together, and is working around the clock to devise solutions for potential problems with the lander; if there are hardware or software problems, or if it’s ended up at an unusual angle. People will really start to lose hope in early January when Mars Express reaches its final polar orbit – it’s the spacecraft Beagle 2 was designed to communicate with.

Two attempts to communicate with Beagle 2 during the last 24 hours – first with the 76 metre (250 feet) Lovell Telescope at Jodrell Bank Observatory in Cheshire, UK, and then this morning with the Mars Odyssey orbiter – ended without receiving a signal. Despite this outcome, fresh attempts to scan for a signal from Beagle 2 will be made over the coming days.

Meanwhile, scientists and engineers are eagerly awaiting ESA’s Mars Express spacecraft return close enough to Mars to try to establish contact with Beagle 2. This may be possible from 4 January 2004.

Mars Express was always intended to be the prime communication relay for Beagle 2, and the lander team is hopeful that a link can be established at that time if it has not already been achieved with Mars Odyssey.

“We need to get Beagle 2 into a period when it can broadcast for a much longer period,” says Professor Colin Pillinger, Beagle 2 lead scientist. “This will happen around the 4 January after the spacecraft has experienced a sufficient number of communication failures to switch to automatic transmission mode.”

Both Professor Pillinger and Professor David Southwood, ESA Director of Science, agreed that the best chance to establish communication with Beagle 2 would now seem to be through Mars Express.

At present, Mars Express is far from the planet and preparing to fire its engines for a major trajectory change that will move it into a polar orbit around Mars.

“We will have no satisfaction until we have a full mission” said Professor Southwood. “Today I’m certainly frustrated, but I’m still confident: let’s wait now until the mothership will have the possibility to get in contact with her baby. With Mars Express we will be using a system that we have fully tested and understand.”

Original Source: ESA News Release

Image credit: PPARC

After NASA’s Mars Odyssey failed to make contact with the British-built Beagle 2 lander on Christmas morning, all hopes were pinned on the Earth-based Jodrell Bank radio telescope to hear its faint signal. After listening for more than two hours, unfortunately, operators failed to tune into the spacecraft’s signal. Then another opportunity to communicate with Odyssey on December 26 failed as well. Mission controllers haven’t completely lost hope, though. When Mars Express reaches its final orbit in early January, it will be the best opportunity to communicate with Beagle 2 and help determine, once and for all, if the spacecraft survived its landing.

Scientists were hopeful that the 250 ft (76 m) Lovell Telescope, recently fitted with a highly sensitive receiver, would be able to pick up the outgoing call from the Mars lander between 19.00 GMT and midnight last night. An attempt to listen out for Beagle’s call home by the Westerbork telescope array in the Netherlands was unfortunately interrupted by strong radio interference.

The next window of opportunity to communicate via Mars Odyssey will open at 17.53 GMT and close at 18.33 GMT this evening, when the orbiter is within range of the targeted landing site on Isidis Planitia.

Another communication session from Jodrell Bank is scheduled between 18.15 GMT and midnight tonight, when Mars will be visible to the radio telescope. It is also hoped that the Stanford University radio telescope in California will be able to listen for the carrier signal on 27 December.

The Beagle 2 team plans to continue using the Mars Odyssey spacecraft as a Beagle 2 communications relay for the next 10 days, after which the European Space Agency’s Mars Express orbiter will become available.

Mars Express, which was always planned to be Beagle 2’s main communication link with Earth, successfully entered orbit around the planet on 25 December and is currently being manoeuvred into its operational polar orbit.

Meanwhile, 13 more attempts to contact Mars Odyssey have been programmed into Beagle 2’s computer. If there is still no contact established after that period, Beagle 2 is programmed to move into auto-transmission mode, when it will send a continuous on-off pulse signal throughout the Martian daylight hours.

The first window of opportunity to communicate with Beagle 2 took place at around 06.00 GMT yesterday, when NASA’s Mars Odyssey spacecraft flew over the planned landing site. In the absence of a signal from the 33 kg lander, the mission team contacted Jodrell Bank to put their contingency plan into operation.

At present, Beagle 2 should be sending a pulsing on-off signal once a minute (10 seconds on, 50 seconds off). Some 9 minutes later, this very slow “Morse Code” broadcast should reach Earth after a journey of some 98 million miles (157 million km).

Although the Beagle’s transmitter power is only 5 watts, little more than that of a mobile phone, scientists are confident that the signal can be detected by the state-of-the-art receiver recently installed on the Lovell Telescope. However, a significant drop in signal strength would require rigorous analysis of the data before it could be unambiguously identified.

Although the ground-based radio telescopes will not be able to send any reply, the new information provided by detection of the transmission from Beagle 2 would enable the mission team to determine a provisional location for Beagle 2. This, in turn, would allow the communications antenna on Mars Odyssey to be directed more accurately towards Beagle 2 during the orbiter’s subsequent overhead passes.

Original Source: PPARC News Release

Image credit: Beagle 2

The European Space Agency confirmed that Mars Express has arrived safely at the Red Planet, ending its 400 million kilometre journey, and beginning its mission to map the surface and search for underground water. The spacecraft began its 37 minute orbital insertion burn at 0247 UTC. Controllers believe that the British-built Beagle 2 also reached Mars at approximately the same time, but the lander failed to make contact with Mars Odyssey, which should have relayed communications back to Earth. Controllers will attempt to make contact again on December 25 at 2200 UTC, this time with the Earth-based Jodrell Bank telescope in Cheshire, UK.

This morning, after a journey lasting 205 days and covering 400 million kilometres, the European Mars Express space probe fired its main engine at 03:47 CET for a 37-minute burn in order to enter an orbit around Mars. This firing gave the probe a boost so that it could match the higher speed of the planet on its orbit around the Sun and be captured by its gravity field, like climbing in a spinning merry-go-round. This orbit insertion manoeuvre was a complete success.

This is a great achievement for Europe on its first attempt to send a space probe into orbit around another planet.

At approximately the same time, the Beagle 2 lander, protected by a thermal shield, entered the Martian atmosphere at high velocity and is expected to have reached the surface at about 03:52 CET. However, the first attempt to communicate with Beagle 2, three hours after landing, via NASA?s Mars Odyssey orbiter, did not establish radio contact. The next contact opportunity will be tonight at 23:40 CET.

The tiny lander was released from the orbiter six days ago on a collision course towards the planet. Before separation, its on-board computer was programmed to operate the lander on its arrival at the surface, by late afternoon (Martian time). According to the schedule, the solar panels must deploy to recharge the on-board batteries before sunset. The same sequence also tells Beagle 2 to emit a signal at a specific frequency for which the Jodrell Bank Telescope, UK, will be listening later tonight. Further radio contacts are scheduled in the days to come.

In the course of the coming week, the orbit of Mars Express will be gradually adjusted in order to prepare for its scientific mission. Mars Express is currently several thousand kilometres away from Mars, in a very elongated equatorial orbit. On 30 December, ESA’s ground control team will send commands to fire the spacecraft’s engines and place it in a polar, less-elongated orbit (about 300 kilometres pericentre, 10000 apocentre, 86? inclination). From there, ESA’s spacecraft will perform detailed studies of the planet’s surface, subsurface structures and atmosphere. Commissioning of some of the on-board scientific instruments will begin towards mid-January and the first scientific data are expected later in the month.

?The arrival of Mars Express is a great success for Europe and for the international science community. Now, we are just waiting for a signal from Beagle 2 to make this Christmas the best we could hope for!? said David Southwood, head of ESA?s Science Directorate. ?With Mars Express, we have a very powerful observatory in orbit around Mars and we look forward to receiving its first results. Its instruments will be able to probe the planet from its upper atmosphere down to a few kilometres below the surface, where we hope to find critical clues concerning the conditions for life, in particular traces of water. We expect this mission to give us a better understanding of our neighbour planet, of its past and its present, answering many questions for the science community and probably raising an even greater number of fascinating new ones. I hope we can see it as opening up a new era of European exploration?.

Original Source: ESA News Release

Image credit: NASA/JPL

The mast-mounted cameras on board the Mars Exploration Rovers, Spirit and Opportunity, will provide the best view so far of the surface of the Red Planet. The cameras are the equivalent of 20/20 human vision – with a resolution of one pixel/millimeter at a range of three metres. Their cameras can pan up and down 90-degrees, and look completely around 360-degrees. The first rover, Spirit, will arrive on Mars on January 3, with Opportunity arriving on January 25.

The Cornell University-developed, mast-mounted panoramic camera, called the Pancam, on board the rovers Spirit and Opportunity will provide the clearest, most-detailed Martian landscapes ever seen.

The image resolution – equivalent to 20/20 vision for a person standing on the Martian surface – will be three times higher than that recorded by the cameras on the Mars Pathfinder mission in 1997 or the Viking Landers in the mid-1970s.

From 10 feet away, Pancam has a resolution of 1 millimeter per pixel. “It’s Mars like you’ve never seen it before,” says Steven Squyres, Cornell professor of astronomy and principal investigator for the suite of scientific instruments carried by the rovers.

Spirit is scheduled to land on Mars on Jan. 3 at 11:35 p.m. EST. Opportunity will touch down Jan. 25 at 12:05 a.m. EST.

The Jet Propulsion Laboratory (JPL) in Pasadena, a division of the California Institute of Technology, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Cornell, in Ithaca, N.Y., is managing the rovers’ science instruments.

Pancam’s mast can swing the camera 360 degrees across the horizon and 90 degrees up or down. Scientists will know a rover’s orientation each day on the Martian surface by using data gained as the camera searches for and finds the sun in the sky at a known time of day. Scientists will determine a rover’s location on the planet by triangulating the positions of features seen on the distant horizon in different directions.

Rover science team member James Bell, Cornell associate professor of astronomy and the lead scientist for Pancam, says that high resolution is important for conducting science on Mars. “We want to see fine details. Maybe there is layering in the rocks, or the rocks are formed from sediments instead of volcanoes. We need to see the rock grains, whether they are wind-formed or shaped by water,” he says.

Also, Pancam is important for determining a rover’s travel plans. Says Bell: “We need to see details of possible obstacles that may be way off in the distance.”

As each twin-lens CCD (charge-coupled device) camera takes pictures, the electronic images will be sent to the rover’s onboard computer for a number of image processing steps, including compression, before the data are sent to Earth.

Each image, reduced to nothing more than a stream of zeros and ones, will be part of a once- or twice-daily stream of information beamed to Earth, a journey that takes 10 minutes. The data will be retrieved by NASA’s Deep Space Network, delivered to mission controllers at JPL and converted into raw images. From there, the images will be sent to the new Mars image processing facility at Cornell’s Space Sciences Building, where researchers and students will hover over computers to produce scientifically useful pictures.

During the surface activity by the rovers, from January to May 2004, there will be daily extensive planning by the Mars scientific team, led by Squyres. Research specialists Elaina McCartney and Jon Proton will participate in these meetings and decide how to implement the plans for Pancam and each rover’s five other instruments.

Processing pictures from 100 million miles away will be no easy feat. It took three years for Cornell faculty, staff and students to precisely calibrate the Pancam lenses, filters and detectors, and to write the software that tells the special camera what to do.

For instance, researchers Jonathan Joseph and Jascha Sohl-Dickstein wrote and perfected software that will produce images of great clarity. One of Joseph’s software routines patches the images together into larger pictures, called mosaics, and another brings out details within single images. Sohl-Dickstein’s software will allow scientists to generate color pictures and conduct spectral analysis, which is important in understanding the planet’s geology and composition.

Extensive work on the camera also was accomplished by Cornell graduates Miles Johnson, Heather Arneson and Alex Hayes. Hayes, who started working on the Mars mission as a Cornell sophomore, built a mock-up of the panoramic camera that aided the delicate color calibration and calculation of the actual Mars camera’s focal length and field of view. Johnson and Arneson spent eight months at JPL running Pancam under Mars-like conditions and collecting calibration data for the camera’s 16 filters.

For the students and recent graduates on the Pancam team, the research has been both valuable experience and education. “I stood inside a clean room at the Jet Propulsion Laboratory and performed testing on the real rovers,” says Johnson. “It was a weird but an exciting feeling standing next to such a really complex piece of equipment that would soon be on Mars.”

Original Source: Cornell University