Posted on by Fraser Cain

Jodrell Listens to Mars, But No Beagle 2

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

Posted on by Fraser Cain

Mars Express Arrives But No Word From Beagle 2

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

Posted on by Fraser Cain

Robert Zubrin Responds to Your Questions

A few weeks ago I reviewed Dr. Robert Zubrin’s newest book, Mars on Earth. I’ve had feedback from Universe Today readers in the past that they they’d like to ask Zubrin a few questions about his goal of sending humans to Mars, so I figured this would be a good chance to get those questions answered. I gave people on the forum a few days to propose their questions and then I selected four questions that I felt were original, and didn’t really cover territory that we’ve heard Zubrin talk about in past (such as in The Case for Mars and Entering Space).

Thanks to everyone who participated, and thanks to Dr. Zubrin for taking the time to respond. If you had fun with this, let me know if there’s anyone else you’d like to throw questions at, and maybe I can track them down.

If you’re interested in the goal of sending humans to Mars, I highly recommend you take a look at the Mars Society, which Robert Zubrin is the President. Click here to visit their website.

1. Dave Mitsky: What do you feel is the most dangerous aspect of the Mars Direct plan?

Zubrin: The ascent from Mars in the Earth Return Vehicle (ERV). The liftoff from Mars followed by trans-Earth injection only requires about half the delta-V as the outbound trip, but there will be much fewer people there to monitor it. So we need really good automated health maintenance and monitoring equipment on the ERV, allowing the launch to be effectively controlled from Earth.

2. Eli: What do you think should be done to make sure a manned Mars mission will not be a “take a photo and not come back for 3 decades” mission ala Apollo?

Zubrin: The problem with Apollo was twofold; that it was the creature of the political class, and the basis upon which it was sold to much of the political class. When it achieved its stated Cold War objective, the elites were then free to dismantle it, as there was no organic space movement with a deeper goal around to sustain it.

We need to make sure that the Mars program is created with the stated goal of opening a new world for humanity, and we need to organize a grassroots movement that supports it and sustains it on that basis.

Black abolitionist leader Frederick Douglas once said “Emancipation would lose half its value were it won by the efforts of white men alone.” He was right. We need to make sure that the Mars program is OUR program, and not THEIR program.

3. Josh: What feedback have the people in power – the government or NASA – given to your ideas?

Zubrin: Many people at the NASA field centers have become supporters of Mars Direct. Some of the headquarters crowd still opposes it as they oppose any destination driven orientation that would force NASA to abandon its constituency-driven method of spending and provide a metric against which results could be measured.

4. exAstro: If it comes down to a cost/benefit analysis we’ll probably never go to Mars- at least by current thinking. So- how do we move beyond that mindset? What would prompt the ultimate decision makers (purse holders) to decide that it’s in “our” best interest to go to Mars? I assume that the technology is not at issue.

Zubrin: I dispute the premise of the question. A cost-benefit analysis demands that we abandon the wasteful Shuttle-era approach of constituency driven spending and return to the highly productive destination driven Apollo era approach.

NASA spending is now 90% of the average Apollo era (1961-1973) level. We spent as much on NASA, in real inflation-adjusted dollars, between 1990 and 2003 as we did between 1961 and 1973. But compare the results. Between 1961-1973 we went from near zero space capability to fly Mercury, Gemini, Apollo, Skylab, Ranger, Mariner, Surveyor, Pioneer Jupiter; we developed hydrogen/oxygen rocket engines, multi-staged heavy lift launch vehicles, in space life support systems, spacesuits, soft landing techniques, lunar rovers, RTGs, space nuclear reactors, nuclear rocket engines, reentry techniques, interplanetary navigation and communication technologies; we built the Deep Space Network, Johnson Space Center, JPL (in the sense it exists today), the Cape Canaveral launch complex, and we inspired a generation of youth to enter science and engineering.

In contrast, between 1990 and 2003 we flew about three-score STS missions, launched and repaired Hubble, launched half a dozen lunar or planetary probes (compared with over 40 for 61-73), and launched a space station which is still less capable than Skylab. So the mission productivity was much less, but the technology return was even worse; as a result of the lack of any forcing function, NASA, despite its claim to be focussing on technology development, developed NO significant new space technologies during the 1990-2003 period, built no new infrastructure, and failed to inspire youth in any way remotely comparable to that it achieved in the sixties.

So if the question is; how do we assure the taxpayers of a real return on their space dollar, there is only one answer; Give NASA a job that is worthy of a $16 billion/year space agency. Assign it the task of sending humans to Mars within a decade.

Posted on by Fraser Cain

One Day to Go for Beagle 2

This time of year, I usually wind things down at Universe Today since the various news sources are all on holiday and there isn’t much to report. This year; however, it’s an entirely different story. The British-built Beagle 2 lander will be touching down on Mars on December 25. Stardust reaches Comet Wild 2 on January 2, and the Mars Exploration Rover arrives on January 3. Things couldn’t be busier.

So, first up… Beagle 2 and Mars Express. The lander is expected to arrive at 0254 UTC on December 25 (9:54 pm EST December 24). We won’t know if Beagle 2 arrived safely for another four hours or so, when Mars Express enters orbit – data won’t arrive back on Earth until 0700 UTC (2:00am EST). Keep your fingers crossed.

The European Space Agency has said they’ll be broadcasting information about the landing live on television, but I haven’t been able to find a link on the web for it (if you know of one, let me know). You can visit their special coverage of the landing and Mars Express arrival here. Or go straight to the Beagle 2 website, where they’ll just be focused on the lander. As I find cool stuff on the web, I’ll let you know.

And make sure you come visit the Universe Today forum and share your thoughts and ideas about the missions with the rest of our community.

Have a happy and safe holiday. See you on Mars!

Fraser Cain
Publisher
Universe Today

Posted on by Fraser Cain

JIMO Ion Engine Passes the Test

Image credit: NASA/JPL

A new ion engine design, under consideration for NASA’s Jupiter Icy Moons Orbiter mission, has been successfully tested. This was the first performance test of the Nuclear Electric Xenon Ion System, which will use a nuclear reactor to generate electricity for the spacecraft’s ion engine – previous ion engines, like on Deep Space 1 and SMART-1 are solar powered. The new engine operated with 10 times the thrust of Deep Space 1, and should be able to run for 10 years; enough time to visit each of Jupiter’s icy moons which are potential candidates for life.

A new ion propulsion engine design, one of several candidate propulsion technologies under study by NASA’s Project Prometheus for possible use on the proposed Jupiter Icy Moons Orbiter mission, has been successfully tested by a team of engineers at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

The event marked the first performance test of the Nuclear Electric Xenon Ion System (Nexis) ion engine at the high-efficiency, high-power, and high-thrust operating conditions needed for use in nuclear electric propulsion applications. For this test the Nexis engine was powered using commercial utility electrical power. Ion engines used on the proposed Jupiter Icy Moons Orbiter spacecraft would draw their power from an on-board space nuclear reactor. The ion engines, or electric thrusters, would propel the orbiter around each of the icy worlds orbiting Jupiter — Ganymede, Callisto and Europa — to conduct extensive, close-range exploration of their makeup, history and potential for sustaining life.

“On the very first day of performance testing, the Nexis thruster demonstrated one of the highest efficiencies of any xenon ion thruster ever tested,” said Dr. James Polk, the principal investigator of the ion engine under development at JPL.

The test was conducted on December 12, in the same vacuum chamber at JPL where earlier this year, the Deep Space 1 flight spare ion thruster set the all time endurance record of 30,352 hours (nearly 3.5 years) of continuous operation. The Nexis engine operated at a power level of over 20 kilowatts, nearly 10 times that of the Deep Space 1 thruster, which enables greater thrust and ultimately higher spacecraft velocities for a given spacecraft mass. It is designed to process two metric tons of propellant, 10 times the capability of the Deep Space 1 engine, and operate for 10 years, two to three times the Deep Space 1 thruster life.

Team members working on the Nexis engine also helped develop the first ion engine ever flown on NASA’s highly successful Deep Space 1 mission, which validated 12 high-risk advanced technologies, among them the use of the first ion engine in space.

“The Nexis thruster is a larger, high performance descendant of the Deep Space 1 thruster that achieves its extraordinary life by replacing the metal, previously used in key components, with advanced carbon based materials,” said Tom Randolph, the Nexis program manager at JPL. “The thruster’s revolutionary performance results from an extensive design process including simulations using detailed computer models developed and validated with the Deep Space 1 life test, and other component test data.”

Unlike the short, high-thrust burns of most chemical rocket engines that use solid or liquid fuels, the ion engine emits only a faint blue glow of electrically charged atoms of xenon – the same gas found in photo flash tubes and in many lighthouse bulbs. The thrust from the engine is as gentle as the force exerted by a sheet of paper held in the palm of your hand. Over the long haul though, the engine can deliver 20 times as much thrust per kilogram of fuel than traditional rockets.

Key to the ion technology is its high exhaust velocity. The ion engine can run on a few hundred grams of propellant per day, making it lightweight. Less weight means less cost to launch, yet an ion-propelled spacecraft can go much faster and farther than any other spacecraft.

“This test, in combination with the recent test of the High Power Electric Propulsion ion engine at NASA’s Glenn Research Center, is another example of the progress we are making in developing the technologies needed to support flagship space exploration missions throughout the solar system and beyond,” said Alan Newhouse, director, Project Prometheus. “We have challenged our team with difficult performance goals and they are demonstrating their ability to be creative in overcoming technical challenges.”

NASA’s Project Prometheus is making strategic investments in space nuclear fission power and electric propulsion technologies that would enable a new class of missions to the outer Solar System, with capabilities far beyond those possible with current power and propulsion systems. The first such mission under study, the Jupiter Icy Moon Orbiter would launch in the next decade and provide NASA significantly improved scientific and telecommunications capabilities and mission design options. Instead of generating only hundreds of watts of electricity like the Cassini or Galileo missions, which used radioisotope thermoelectric generators, the Jupiter Icy Moons Orbiter could have up to tens of thousands of watts of power, increasing the potential science return many times over.

Development of the Nexis ion engine is being carried out by a team of engineers from JPL; Aerojet, Redmond, Wash.; Boeing Electron Dynamic Devices, Torrance, Calif.; NASA’s Marshall Space Flight Center, Huntsville, Ala.; Colorado State University, Fort Collins, Colo.; Georgia Institute of Technology, Atlanta, Ga.; and the Aerospace Corporation, Los Angeles, Calif.

For more information about Project Prometheus on the Internet, visit: http://spacescience.nasa.gov/missions/prometheus.htm .

Information on the proposed Jupiter Icy Moons Orbiter mission is available at: NASA Jimo MIssion .

Original Source: NASA/JPL News Release

Posted on by Fraser Cain

Dark Matter Bends Light from a Distant Quasar

Image credit: SDSS

Gravitational lensing happens when the light from a distant object, such as a quasar, is distorted by the gravity of a closer object. Astronomers have discovered just such a lens, where the distortions are so great, they have to be caused by a significant amount of dark matter – the visible material alone couldn’t be responsible. Dark matter is predicted by its gravitational influence on galaxies and stars in the Universe, but so far, astronomers aren’t really sure what it is; whether it’s just regular matter which is too cold to be seen from Earth, or some kind of exotic particle.

Sloan Digital Sky Survey scientists have discovered a gravitationally lensed quasar with the largest separation ever recorded, and, contrary to expectations, found that four of the most distant, most luminous quasars known are not gravitationally lensed.

Albert Einstein’s Theory of General Relativity predicts that the gravitational pull of a massive body can act as a lens, bending and distorting the light of a distant object. A massive structure somewhere between a distant quasar and Earth can “lens” the light of a quasar, making the image substantially brighter and producing several images of one object.

In a paper published in the December 18/25 edition of NATURE magazine, a Sloan Digital Sky Survey (SDSS) team led by University of Tokyo graduate students Naohisa Inada and Masamune Oguri report that four quasars in close proximity are, in fact, the light from one quasar split into four images by gravitational lensing.

More than 80 gravitationally lensed quasars have been discovered since the first example was found in 1979. A dozen of the cataloged lensed quasars are SDSS discoveries, of which half are the result of the work of Inada and his team.

But what makes this latest finding so dramatic is that the separation between the four images is twice as large as that of any previously known gravitationally lensed quasar. Until the discovery of this quadruple lens quasar, the largest separation known in a gravitationally lensed quasar was 7 arcseconds. The quasar found by the SDSS team lies in the constellation Leo Minor; it consists of four images separated by 14.62 arcseconds.

In order to produce such a large separation, the concentration of matter giving rise to the lensing has to be particularly high. There is a cluster of galaxies in the foreground of this gravitational lens; the dark matter associated with the cluster must be responsible for the unprecedented large separation.

“Additional observations obtained at the Subaru 8.2 meter telescope and Keck telescope confirmed that this system is indeed a gravitational lens,” explains Inada. “Quasars split this much by gravitational lensing are predicted to be very rare, and thus can only be discovered in very large surveys like the SDSS.”

Oguri added: “Discovering one such wide gravitational lens out of over 30,000 SDSS quasars surveyed to date is perfectly consistent with theoretical expectations of models in which the universe is dominated by cold dark matter. This offers additional strong evidence for such models.” (Cold dark matter, unlike hot dark matter, forms tight clumps, the kind that causes this kind of gravitational lens.)

“The gravitational lens we have discovered will provide an ideal laboratory to explore the relation between visible objects and invisible dark matter in the universe,” Oguri explained.

In a second paper to be published in the Astronomical Journal in March 2004, a team led by Gordon Richards of Princeton University used the high resolution of the Hubble Space Telescope to examine four of the most distant known quasars discovered by SDSS for signs of gravitational lensing.

Looking to great distances in astronomy is looking back in time. These quasars are seen at a time when the universe was less than 10percent of its present age. These quasars are tremendously luminous, and are thought to be powered by enormous black holes with masses several billion times that of the Sun. The researchers said it is a real mystery how such massive black holes could have formed so early in the universe. Yet if these objects are gravitationally lensed, SDSS researchers would infer substantially smaller luminosities and therefore black hole masses, making it easier to explain their formation.

“The more distant a quasar, the more likely a galaxy lies between it and the viewer. This is why we expected the most distant quasars to be lensed,” explained SDSS researcher Xiaohui Fan of the University of Arizona. However, contrary to expectations, none of the four shows any sign of multiple images that is the hallmark of lensing.

“Only a small fraction of quasars are gravitationally lensed. However, quasars this bright are very rare in the distant universe. Since lensing causes quasars to appear brighter and therefore easier to detect, we expected that our distant quasars were the ones most likely to be lensed,” suggested team member Zoltan Haiman of Columbia University.

“The fact that these quasars are not lensed says that astronomers have to take seriously the idea that quasars a few billion times the mass of the Sun formed less than a billion years after the Big Bang”, said Richards. “We’re now looking for more examples of high-redshift quasars in the SDSS to give theorists even more supermassive black holes to explain.”

Original Source: SDSS News Release

Posted on by Fraser Cain

Rover Cameras Will Be Like Human Vision on Mars

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

Posted on by Fraser Cain

Three Dusty Galaxy Images

Image credit: ESO

The European Southern Observatory has released three new images of distant spiral galaxies, which were taken while astronomers were searching for quasars. NGC 613 is a beautiful barred spiral galaxy in the southern constellation of Sculptor; NGC 1792 is a starburst spiral galaxy located in the southern constellation of Columba; and NGC 3627 is also known as Messier 66 and located in the constellation Leo.

Not so long ago, the real nature of the “spiral nebulae”, spiral-shaped objects observed in the sky through telescopes, was still unknown. This long-standing issue was finally settled in 1924 when the famous American astronomer Edwin Hubble provided conclusive evidence that they are located outside our own galaxy and are in fact “island universes” of their own.

Nowadays, we know that the Milky Way is just one of billions of galaxies in the Universe. They come in vastly different shapes – spiral, elliptical, irregular – and many of them are simply beautiful, especially the spiral ones.

Astronomers Mark Neeser from the Universit?ts-Sternwarte M?nchen (Germany) and Peter Barthel from the Kapteyn Institute in Groningen (The Netherlands) were clearly not insensitive to this when they obtained images of three beautiful spiral galaxies with ESO’s Very Large Telescope (VLT). They did this in twilight during the early morning when they had to stop their normal observing programme, searching for very distant and faint quasars.

The resulting colour images (ESO PR Photos 33a-c/03) were produced by combining several CCD images in three different wavebands from the FORS multi-mode instruments.

The three galaxies are known as NGC 613, NGC 1792 and NGC 3627. They are characterized by strong far-infrared, as well as radio emission, indicative of substantial ongoing star-formation activity. Indeed, these images all display prominent dust as well as features related to young stars, clear signs of intensive star-formation.

NGC 613
NGC 613 is a beautiful barred spiral galaxy in the southern constellation Sculptor. This galaxy is inclined by 32 degrees and, contrary to most barred spirals, has many arms that give it a tentacular appearance.

Prominent dust lanes are visible along the large-scale bar. Extensive star-formation occurs in this area, at the ends of the bar, and also in the nuclear regions of the galaxy. The gas at the centre, as well as the radio properties are indicative of the presence of a massive black hole in the centre of NGC 613.

NGC 1792
NGC 1792 is located in the southern constellation Columba (The Dove) – almost on the border with the constellation Caelum (The Graving Tool) – and is a so-called starburst spiral galaxy. Its optical appearance is quite chaotic, due to the patchy distribution of dust throughout the disc of this galaxy. It is very rich in neutral hydrogen gas – fuel for the formation of new stars – and is indeed rapidly forming such stars. The galaxy is characterized by unusually luminous far-infrared radiation; this is due to dust heated by young stars.

M 66 (NGC 3627)
The third galaxy is NGC 3627, also known as Messier 66, i.e. it is the 66th object in the famous catalogue of nebulae by French astronomer Charles Messier (1730 – 1817). It is located in the constellation Leo (The Lion).

NGC 3627 is a beautiful spiral with a well-developed central bulge. It also displays large-scale dust lanes. Many regions of warm hydrogen gas are seen throughout the disc of this galaxy. The latter regions are being ionised by radiation from clusters of newborn stars. Very active star-formation is most likely also occurring in the nuclear regions of NGC 3627.

The galaxy forms, together with its neighbours M 65 and NGC 3628, the so-called “Leo Triplet”; they are located at a distance of about 35 million light-years. M 66 is the largest of the three. Its spiral arms appear distorted and displaced above the main plane of the galaxy. The asymmetric appearance is most likely due to gravitational interaction with its neighbours.

Original Source: ESO News Release

Posted on by Fraser Cain

Delta II Launches GPS Satellite

Image credit: Boeing

A Boeing Delta II rocket successfully launched a Global Positioning System satellite for the US Air Force on December 21. The rocket lifted off from Cape Canaveral at 0805 UTC (3:05 EST), and the satellite was deployed 68 minutes later. The satellite, designated GPS IIR-10 was the tenth of 21 IIR class GPS satellites that Boeing will be responsible for launching. The next scheduled Delta launch will also be carrying a GPS satellite; it’s expected to lift off in early 2004.

A Boeing [NYSE: BA] Delta II rocket has successfully deployed a Global Positioning System (GPS) satellite for the U.S. Air Force. This satellite, GPS IIR-10, was the tenth of 21 IIR class GPS satellites Boeing will launch for the Air Force.

Liftoff of the Delta II occurred at 3:05 a.m. EST from Space Launch Complex 17A, Cape Canaveral Air Force Station, Fla. The deployment sequence was completed in 68 minutes at 4:13 a.m. EST.

The GPS satellite, which will orbit nearly 11,000 miles above the Earth, was launched aboard a Delta II 7925-9.5 vehicle.

?Our Delta team has done an outstanding job in supporting the customer, by providing another flawless launch,? said Dan Collins, vice president and program manager, Delta Programs, for Boeing. ?This successful `Delta launch re-affirms our pride in being a part of the GPS program, which is so vital to our nation?s national security.?

Operated by U.S. Air Force Space Command, the GPS constellation provides precise navigation and timing to worldwide military and civilian users 24-hours a day, in all weather conditions. For the warfighter, GPS has enabled the development and use of cost-effective precision guided munitions, and is considered a major component of DoD?s transformational architecture plans.

The next Delta II mission will carry the GPS IIR-11satellite, with the launch scheduled for the first quarter of 2004 from SLC-17B, Cape Canaveral Air Force Station, Fla.

Boeing Launch Services Inc., based in Huntington Beach, Calif., is responsible for the marketing and sales of the Sea Launch and Delta family of launch vehicles to Boeing national security, civil space and commercial customers.
A unit of The Boeing Company, Integrated Defense Systems is one of the world?s largest space and defense businesses. Headquartered in St. Louis, Boeing Integrated Defense Systems is a $25 billion business. It provides systems solutions to its global military, government, and commercial customers. It is a leading provider of intelligence surveillance, and reconnaissance; the world?s largest military aircraft manufacturer; the world?s largest satellite manufacturer and a leading provider of space-based communications; the primary systems integrator for U.S. missile defense; NASA?s largest contractor; and a global leader in launch services.

Original Source: Boeing News Release

Posted on by Fraser Cain

Rovers Will Dig Trenches with Their Wheels

Image credit: NASA/JPL

Scientists are always looking for more ways to cram scientific instruments into spacecraft, and they’ve come up with an innovative idea for the Mars Exploration rovers: using the wheels to dig trenches to see what the environment on Mars is like a few centimetres beneath the surface. Researchers from Cornell University perfected a technique where the rover locks all but one of its six wheels, and then uses the final wheel to churn up the dirt – tests in the lab allowed them to get at material which was more than 10 cm deep.

After the twin Mars Exploration Rovers bounce onto the red planet and begin touring the Martian terrain in January, onboard spectrometers and cameras will gather data and images — and the rovers’ wheels will dig holes.

Working together, a Cornell University planetary geologist and a civil engineer have found a way to use the wheels to study the Martian soil by digging the dirt with a spinning wheel. “It’s nice to roll over geology, but every once in a while you have to pull out a shovel, dig a hole and find out what is really underneath your feet,” says Robert Sullivan, senior research associate in space sciences and a planetary geology member of the Mars mission’s science team. He devised the plan with Harry Stewart, Cornell associate professor of civil engineering, and engineers at the Jet Propulsion Laboratory (JPL) in Pasadena.

The researchers perfected a digging method to lock all but one of a rover’s wheels on the Martian surface. The remaining wheel will spin, digging the surface soil down about 5 inches, creating a crater-shaped hole that will enable the remote study of the soil’s stratigraphy and an analysis of whether water once existed. For controllers at JPL, the process will involve complicated maneuvers — a “rover ballet,” according to Sullivan — before and after each hole is dug to coordinate and optimize science investigations of each hole and its tailings pile.

JPL, 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 science suite of instruments carried by the two rovers.

Each rover has a set of six wheels carved from aluminum blocks, and inside each wheel hub is a motor. To spin a wheel independently, JPL operators will simply switch off the other five wheel motors. Sullivan, Stewart and Cornell undergraduates Lindsey Brock and Craig Weinstein used Cornell’s Takeo Mogami Geotechnical Laboratory to examine various soil strengths and characteristics. They also used Cornell’s George Winter Civil Infrastructure Laboratory to test the interaction of a rover wheel with the soil. Each rover wheel has spokes arranged in a spiral pattern, with strong foam rubber between the spokes; these features will help the rover wheels function as shock absorbers while rolling over rough terrain on Mars.

In November, Sullivan used JPL’s Martian terrain proving ground to collect data on how a rover wheel interacts with different soil types and loose sand. He used yellow, pink and green sand — dyed with food coloring and baked by Brock. Sullivan used a stack of large picture frames to layer the different colored sands to observe how a wheel churned out sloping tailings piles and where the yellow, pink and green sand finally landed. “Locations where the deepest colors were concentrated on the surface suggest where analysis might be concentrated when the maneuver is repeated for real on Mars,” he says.

Stewart notes similarities between these tests and those for the lunar-landing missions in the late-1960s, when engineers needed to know the physical characteristics of the moon’s surface. Back then, geologists relied on visual observations from scouting missions to determine if the lunar lander would sink or kick up dust, or whether the lunar surface was dense or powdery.

“Like the early lunar missions, we’ll be doing the same thing, only this time examining the characteristics of the Martian soil,” Stewart says. “We’ll be exposing fresh material to learn the mineralogy and composition.”

Original Source: Cornell News Release