Category: Mars

Image credit: NASA/JPL

NASA engineers have been working through a problem with one of the Mars rovers currently traveling to the Red Planet, and they think they’ve got a solution. Back in August, engineers detected that Spirit’s M?ssbauer spectrometer – a device for identifying iron-bearing rocks – was sending back incorrect readings. They’ve been able to compensate for the readings, so long as Spirit continues to behave on Mars as it’s working right now. The rovers will land on Mars in January 2004.

A series of tests of one of the science instruments on NASA’s Mars Exploration Rover Spirit has enabled engineers and scientists to identify how to work around an apparent problem detected in August.

Tests now indicate that all of the science instruments on both Spirit and its twin, Opportunity, are in suitable condition to provide full capabilities for examining the sites on Mars where they will land in January.

Spirit’s M?ssbauer spectrometer, a tool for identifying the types of iron-bearing minerals in rocks and soil, returned data that did not fit expectations during its first in-flight checkup three months ago. A drive system that rapidly vibrates a gamma-ray source back and forth inside the instrument appeared to show partial restriction in its motion.

“The drive system is adjustable. We can change its velocity. We can change its frequency,” said Dr. Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers’ science instruments. “We’ve found a set of parameters that will give us good M?ssbauer science if the instrument behaves on Mars the way it is behaving now.”

The corrective countermeasures include using a higher frequency of back-and-forth motion. “With these settings, whatever happened during launch will not decrease the quality of the data we get from the instrument,” said Dr. G?star Klingelh?fer, of Johannes Gutenberg University, Mainz, Germany, lead scientist for the M?ssbauer spectrometers on both rovers. “The instrument was designed with enough margin in its performance that we can make this change with no significant science impact.”

A possible explanation for the instrument’s behavior since launch is that intense vibration of the spacecraft during launch shook something inside the spectrometer slightly out of position, he said.

Landings on Mars are risky. Most attempts over the years have failed. And even if the spacecraft survives the landing, there is the potential that individual components could be damaged. “One remaining issue with the M?ssbauer Spectrometer on Spirit, as with all the instruments, is that we can’t be one hundred percent sure it?ll operate on Mars the way it?s operating now,” Squyres said. “We?ll breathe easier once we?ve done all our post-landing health checks.”

Another fact that has emerged from the in-flight checkouts of the M?ssbauer spectrometers on both spacecraft is that the internal calibration channel of the M?ssbauer spectrometer on Opportunity is not functioning properly. But because the instrument has the redundancy of a separate, completely independent external calibration method, this problem will not hamper use of that instrument, Squyres said.

Spirit is on course to arrive at Mars’ Gusev Crater at 04:35 Jan. 4, 2004, Universal Time, which is 8:35 p.m. Jan. 3, Pacific Standard Time and 11:35 p.m. Jan. 3, Eastern Standard Time. (These are “Earth received times,” meaning they reflect the delay necessary for a speed-of-light signal from Mars to reach Earth; on Mars, the landing will have happened nearly 10 minutes earlier.) Three weeks later, Opportunity will arrive at a level plain called Meridiani Planum on the opposite side of Mars from Gusev. Each rover will examine its landing area for geological evidence about the history of water there, key information for assessing whether the site ever could have been hospitable to life.

As of 13:00 Universal Time on Nov. 5 (5 a.m. PST; 8 a.m. EST), Spirit will have traveled 367.4 million kilometers (228.3 million miles) since its launch on June 10 and will still have 119.6 million kilometers (74.3 million miles) to go before reaching Mars. Opportunity will have traveled 296 million kilometers (184 million miles) since its launch on July 7 and will still have 160 million kilometers (99.2 million miles) to go to reach Mars.

The Jet Propulsion Laboratory, a division of the California Institute of Technology, manages the Mars Exploration Rover project for NASA’s Office of Space Science, Washington, D.C. Additional information about the project is available from JPL at http://mars.jpl.nasa.gov/mer and from Cornell University, Ithaca, N.Y., at http://athena.cornell.edu.

Original Source: NASA/JPL News Release

Image credit: NASA

Astronomers have uncovered a green mineral on Mars called olivine that could indicate that the planet has been completely dry for at least a billion years, since the mineral was exposed to the Martian air. Olivine is found in many rocks on Earth, and it’s highly susceptible to chemical weathering. If liquid water was present at any time in the past, the olivine would have altered into other materials – but this hasn’t happened. The areas will be further investigated in 2005 by the upcoming Mars Reconnaissance Orbiter, which has 100 times the resolution of the Mars Global Surveyor.

The presence of a common green mineral on Mars suggests that the Red Planet could have been cold and dry since the mineral has been exposed, which may have been more than a billion years ago, according to new research appearing in the Oct. 24 edition of Science.

Todd Hoefen, a Denver-based U.S. Geological Survey (USGS) geophysicist, led a team of researchers from USGS, Arizona State University and NASA, that found abundant quantities of olivine on Mars at least locally. They based their conclusions on data obtained from a Thermal Emission Spectrometer (TES) carried by NASA’s Mars Global Surveyor (MGS) spacecraft.

Olivine, a transparent, green-colored mineral found in many rocks containing magnesium and iron (mafic igneous rocks), is highly susceptible to chemical weathering and readily alters to other minerals in the presence of liquid water (minerals such as iddingsite, goethite, serpentine, chlorite, smectite, maghemite and hematite). Except for trace amounts of hematite, which gives Mars its red color, none of these other weathering products have been detected at kilometer scales on Mars.

The team detected a 30,000 square kilometer (18,720 square mile) area rich in olivine, in the Nili Fossae region of Mars, which makes up ~ 0.02 % of the planet by area. Nili Fossae has been interpreted as a complex of grabens (long depressions between geologic faults) and fractures related to the formation of the Isidis impact basin, where post-impact faulting most plausibly exposed the locally abundant olivine. They have also found smaller deposits of olivine all over the planet, all indicating a surface at least regionally dominated by volcanic processes.

The fact that so much olivine is exposed at the surface in the Nili Fossae region indicates that there has been little to no weathering due to water, thus no liquid water-mineral chemical reactions. The absolute age of the surface is somewhat uncertain but is probably over 3 billion years old, on the basis of our best current estimates. If, however, such surfaces have been more recently exposed, one would not expect for the olivine to have been chemically altered due to the current environmental conditions on Mars (cold, dry).

It took approximately three years for the MGS spacecraft and the TES instrument to gather the data for the analysis, and another year for scientists to analyze and fully interpret the results. The MGS spacecraft is healthy and continues to map Mars.

“The detection of minerals such as olivine that serve as fingerprints of the geological processes responsible for forming the Martian surface we are exploring today is a vital part of the overall Mars Exploration Program science strategy,” stated Dr. Jim Garvin, NASA’s Lead Scientist for Mars at NASA Headquarters. “The provocative findings by Hoefen and his team will be further investigated when NASA’s 2005 Mars Reconnaissance Orbiter turns its hyperspectral imaging spectrometer, with 100 times the spatial resolution of the MGS TES instrument, on these olivine-rich regions in a few years,” continues Garvin.

The USGS serves the nation by providing reliable scientific information to describe and understand the Earth; minimize loss of life and property from natural disasters; manage water, biological, energy, and mineral resources; and enhance and protect our quality of life.

Original Source: NASA News Release

Image credit: NASA

Is there life on Mars? A team of scientists from the University of Glasgow have developed a method they believe will help detect evidence of life in ancient rocks – perhaps helping uncover if there’s life on Mars. With their technique, the rocks are crushed to release tiny amounts of liquid water, and then special detectors are used to search for the presence of biomolecules in the water. Once the technique has been proven to work, the researchers believe it could be miniaturized and flown aboard future Mars landers.

A new UK project could help detect evidence of life on Mars and improve our understanding of how life evolved on Earth. The aim is to develop a technique that can identify biomolecules in water that have been trapped in rocks for millions to billions of years.

The three-year initiative will be carried out by geologists and bioengineers at the University of Aberdeen and the University of Glasgow, with funding from the UK’s Engineering and Physical Sciences Research Council.

The initiative is being led by Dr John Parnell of the University of Aberdeen’s Geology and Petroleum Geology Department, in collaboration with Professor Jonathan Cooper of the University of Glasgow’s Department of Electronics.

Professor Cooper says, ‘With our collaborators in Aberdeen, we are fortunate to have the possibility of working on one of the most exciting projects in the universe, the search for life on other planets!’

As well as analysing samples from Earth, the technique could be used to obtain important information from water sealed within rock samples brought back from Mars. The team will also consider how the technique could be miniaturised for incorporation into spacecraft that travel to other planets.

The research will explore significant technological challenges at the interface between the physical sciences and engineering. These include microfluidic methods for sample pre-concentration (ie the extraction and handling of exceptionally small amounts of fluid), single molecule detection technologies to locate very small amounts of biomaterials and the elimination of contaminants.

The project is highly innovative, attempting to access a source of biomolecules that have not been tapped before. Analysis of material dating from the time before the Earth’s fossil record became extensive is a major project aim, potentially resulting in our knowledge of the development of life on Earth being significantly enhanced.

Original Source: University of Glasgow News Release

Image credit: ESA

Three European firms have won contracts to design the European Space Agency’s ExoMars spacecraft – a mission that is expected to launch to the Red Planet in 2009. ExoMars will consist of an orbiter and a rover that will land on Mars, and explore some of its surface. The three winning teams are Alenia Spazio, Alcatel Space and EADS Astrium. Teams have also been selected to provide design studies for the Mars Sample Return mission – where a spacecraft will land on Mars, collect samples, and then return them to Earth.

A major milestone in ESA?s long-term Aurora programme of Solar System exploration has been passed with the announcement of the winners of competitive contracts for two of the programme?s key robotic missions ? ExoMars and Earth re-entry Vehicle Demonstrator (EVD).

A major milestone in ESA?s long-term Aurora programme of Solar System exploration has been passed with the announcement of the winners of competitive contracts for two of the programme?s key robotic missions ? ExoMars and Earth re-entry Vehicle Demonstrator (EVD).

Alenia Spazio (Italy), Alcatel Space (France) and EADS Astrium (France) are heading the three industrial teams selected to carry out a full mission design for ExoMars, the Aurora exobiology mission to Mars.

At the same time, two industrial teams, headed by EADS LV (Launch Vehicles) of France and Surrey Satellite Technology Limited (SSTL) of the United Kingdom respectively, have been selected for the pre-development phase (officially known as Pre-Phase A) of the EVD mission.

?Following the Invitations To Tender (ITTs) for these contracts, issued in April-May 2003, there was an overwhelming and enthusiastic response from industry,? said Bruno Gardini, Aurora Project Manager.

?We were delighted by the number and the excellence of the proposals received,? he added. ?It was also pleasing to see that many of them included new, innovative ideas from industry.?

ExoMars
The ExoMars mission, to be launched in 2009, is the first of the major Flagship missions in the Aurora programme. It includes an orbiter and a descent module that will land a large (200 kg), high-mobility rover on the surface of Mars. After delivery of the lander/rover, the ExoMars orbiter will also operate as a data relay satellite between the Earth and the vehicle on the Martian surface.

The primary objective of the ExoMars rover will be to search for signs of life, past or present, on the Red Planet. Additional measurements will be taken to identify potential surface hazards for future human missions, to determine the distribution of water on Mars and to measure the chemical composition of the surface rocks.

Three parallel Phase A studies for the ExoMars Mission will be carried out by industrial teams that include companies from ESA member states and Canada:

• * Alenia Spazio (Italy) with subcontractors OHB (Germany), GMV (Spain), SEA (UK), SSC (UK) and Laben (Italy).
• * Alcatel Space (France) with subcontractors Deimos (Spain), ETCA (Belgium), Fluid Gravity Engineering (UK), Kayser Threde (Germany), Laben (Italy), MD Robotics (Canada), NGC Aerospatiale (Canada), QinetiQ (UK), Vorticity (UK).
• * EADS Astrium (France) with subcontractors Astrium Ltd. (UK), EADS LV (France) and SAS (Belgium).

The contracts cover the design of the entire ExoMars mission, from launch, through the long interplanetary voyage to the landing of the rover on the planet.

?This is an exciting landmark for the Aurora programme, since these are the first contracts dedicated to mission development rather than technical studies,? said Gardini.

?With the participation of all major European aerospace companies, the proposed concepts will make the best use of their extensive experience, gathered over many years, in the design and development of interplanetary missions,? he said.

?The studies will also bring to fruition several years of efforts from national and international programmes in investigating and planning Mars missions.

?From the quality of the proposals, the agency is very confident that the technical baseline will be fully consolidated by the end of the Phase A studies and that the spacecraft design will then be defined to a level of detail commensurate with a prompt start of Phase B.?

Depending on the availability of funding, the Phase B studies for ExoMars are planned to start in 2004.

Earth re-entry Vehicle Demonstrator (EVD)
The second Aurora Flagship mission is a Mars Sample Return (MSR), planned for 2011. Its main goal will be the retrieval of rock samples from the Martian surface and subsurface for subsequent analysis in laboratories on Earth.

In order to ensure the success of this challenging mission, a number of new technologies will have to be developed and tested. Conceived as a small, technology-driven Arrow-class mission, the Earth re-entry Vehicle Demonstration will be used to validate the design of the small MSR capsule that will bring back the precious samples of Martian soil.

The EVD is expected to be launched in 2007. The baseline mission foresees the insertion into a highly elliptical Earth orbit of a small spacecraft carrying a re-entry capsule. In order to reproduce the final phase of a typical Mars return mission, the capsule will then carry out a ballistic re-entry into Earth?s atmosphere at speeds of up to 45,000 km/h.

Two industrial teams have been selected for the parallel EVD mission Pre-Phase A studies. The concept presented by the industrial team, under the leadership of EADS LV (France) with the participation of OHB System (Germany) and Plansee (Austria) is solidly based on the experience of past projects.

The industrial team led by SSTL (UK), a company well known for its experience in small highly integrated spacecraft, has devised a very innovative concept well adapted for a small technology mission. The participation of highly specialised companies, Fluid Gravity Engineering (UK), Kayser Threde GmbH (D) and Vorticity Ltd. (UK) ensures an excellent coverage of the mission?s most critical technologies.

?The expectations are for highly competitive and exciting Pre-Phase A studies,? said Gardini.

The next Aurora contract for Phase A studies will concern the Mars Sample Return mission. Industrial proposals were submitted on 1 August and the evaluation is nearly completed. The names of the selected companies are expected to be announced in early October.

Original Source: ESA News Release

Image credit: NASA/JPL

NASA has released 10,232 new images of the Red Planet taken by the Mars Global Surveyor spacecraft, including wind whipped polar dunes, steep-walled valleys, and boulder-strewn terrain. The images were taken over the course of several months, from August 2002 to February 2003, and they include views all over the planet. This brings the total number of images taken by Surveyor in six years of observation to more than 134,000.

Thousands of newly released portraits of martian landscapes from NASA’s Mars Global Surveyor spacecraft testify to the diversity of ways geological processes have sculpted the surface of our neighboring planet.

Swirling textures that some scientists call “taffy-pull terrain? fill one new image from the plains of southern Mars, for example. Other images reveal details of features such as wind-whipped polar dunes and steep-sided valleys carved by flowing water or lava.

The 10,232 newly released pictures from the Mars Orbiter Camera on Mars Global Surveyor bring the total number of images in the camera’s online gallery to more than 134,000. The new batch is at: http://www.msss.com/mars_images/moc/2003/09/30/.

“Mars just keeps astounding us with its complexity,” said Dr. Ken Edgett, staff scientist for Malin Space Science Systems, San Diego, Calif, which built and operates the Mars Orbiter Camera.

The new group of images was taken between August 2002 and February 2003, then validated and archived by the camera team. It includes many views of north polar terrain, extremely clear-atmosphere views of a deep southern basin named Hellas Planitia, and a variety of martian landforms between the north pole and the southern middle latitudes. The pictures show martian surface details down to the size of a large sport utility vehicle.

Since Mars Global Surveyor began orbiting Mars six years ago, the mission has provided a wealth of information about the planet’s atmosphere and interior, as well at its surface.

Evaluation of landing sites for NASA’s Spirit and Opportunity, two Mars Exploration Rover spacecraft due to land on Mars in January 2004, relied heavily on mineral mapping, detailed imagery and topographic measurements by Global Surveyor.

Additional information about Mars Global Surveyor is available online at: http://mars.jpl.nasa.gov/mgs/.

In addition to semi-annual releases of large collections of archived pictures, the Mars Orbiter Camera team posts a new image daily and recently began soliciting public suggestions for camera targets on Mars. The full gallery is available at: http://www.msss.com/moc_gallery/.

Original Source: NASA News Release

Image credit: NASA/JPL

For the past few weeks, NASA has been letting the public select targets for the Mars Global Surveyor spacecraft, and the first image was released today. The location was the summit crater of a giant volcano called Pavonis Mons – the walls and floor of the crater are covered with thick dust. It was suggested by U.S. Marine Lance Corporal Robert F. Sanders, of Jacksonville, N.C. from the hundreds of selections submitted so far. Mars Global Surveyor has taken 120,000 images of the planet’s surface in high detail, but this is only 3% of the entire planet.

If you were given a chance to aim the camera on NASA’s Mars Global Surveyor Mars Orbiter and take a picture of something on the red planet, what would you shoot?

Now we know, after NASA released today the first picture selected from hundreds of public suggestions. The photo reveals a thick layer of dust blanketing the floor and wall of the summit crater atop a tall volcano called Pavonis Mons.

“It’s such a thrill to see it,” said U.S. Marine Lance Corporal Robert F. Sanders, of Jacksonville, N.C., who suggested the crater close up as a photo target for the Mars Global Surveyor camera. “I spent hours coming up with suggestions, but I didn’t know whether any of them would be accepted.”

The resulting picture shows details as small as a large SUV in a strip of ground about 9 kilometers (5.6 miles) long within the summit crater of Pavonis Mons.

“We’ve received hundreds of really good ideas since we began accepting public suggestions last month,” said Dr. Ken Edgett, staff scientist for Malin Space Science Systems, which operates the Mars Orbital Camera. “We were excited last week, when the predicted ground track intersected a publicly suggested location for the first time.” Accepted targets are not imaged until the spacecraft’s regular orbiting pattern goes directly over them.

The captioned image and an accompanying wide-angle view for context are available on the Internet from NASA’s Jet Propulsion Laboratory, Pasadena, Calif., at http://photojournal.jpl.nasa.gov/catalog/PIA04735. They are also available from Malin Space Science Systems, San Diego, at http://www.msss.com/mars_images/moc/2003/09/12/.

The camera on Mars Global Surveyor has returned more than 120,000 pictures since the spacecraft began orbiting Mars on Sept. 12, 1997. Still, its high-resolution images have covered only about three percent of the planet’s surface. Three percent of Mars, while seemingly small, represents a huge amount of “real estate,” or nearly 5 million square kilometers (about 3 million square miles), that has been observed at spectacular resolution.

Information about how to submit suggestions is available on the Internet at the Mars Orbiter Camera Target Request Site, at http://www.msss.com/plan/intro.

“Taking public suggestions enhances the science return,” Edgett said. “Every suggestion we get has the potential for discovery.”

“As Mars Global Surveyor continues its legacy of SUV-scale exploration, we’re excited to offer for the first time an innovative approach for direct public participation in Mars exploration,” said Dr. Jim Garvin, NASA’s lead scientist for Mars. “Increasing the breadth of science activities, by working together with the public to uncover the mysteries of Mars, is an important part of NASA’s mission to inspire the next generation of explorers.”

Information about Mars Global Surveyor is available on the Internet at http://mars.jpl.nasa.gov/mgs.

JPL, a division of the California Institute of Technology, Pasadena, manages Mars Global Surveyor for NASA’s Office of Space Science in Washington. JPL’s industrial partner is Lockheed Martin Space Systems, Denver, which developed and operates the spacecraft. Malin Space Science Systems and the California Institute of Technology built the Mars Orbiter Camera. Malin Space Science Systems operates the camera from facilities in San Diego.

Original Source: NASA/JPL News Release

It’s been a couple of days since Mars made its closest approach so it’s time for the news media to completely and utterly forget about it and move onto something new. The reality, though, is that Mars is going to remain bright and close for several months. It’ll still incredible in many small telescopes well into September and even October. Even better than that, it will be visible higher in the sky at earlier times. Instead of waiting for it to rise through the murk at the horizon, you can just wait until it gets dark and then, bang, there it is.

If you tried to attend an event, I know everywhere was busy. I’ve heard stories of two-hour lineups just for a chance to look through a telescope. Yikes. Some astronomy clubs have chosen to organize their events in September, so take another look at my list of Mars 2003 events.

Fraser Cain
Publisher
Universe Today

P.S. I’ve had complaints from AOL subscribers that they aren’t receiving the newsletter – I suspect some aggressive SPAM-filter. If you’re on AOL, can you let me know if you’re receiving this?

Image credit: UKIRT

Astronomers are searching for evidence of past water on Mars from the comfort of an observatory in Hawaii. They’re using the United Kingdom Infrared Telescope (UKIRT) to map the spectral signature given off of minerals on the Red Planet’s surface. They’re looking for minerals, such as hydrated clay, which would indicate the past presence of liquid water. NASA’s two Mars Exploration Rovers will be searching for similar signs on Mars when they arrive in January 2004.

As Mars makes its closest approach in almost 60,000 years, two Australian astronomers have used the United Kingdom Infrared Telescope (UKIRT) in Hawai`i to look for signs that the planet once had liquid water – and so may have hosted life.

Dr. Jeremy Bailey of the Anglo-Australian Observatory and the Australian Centre for Astrobiology (ACA) at Macquarie University in Sydney, and Sarah Chamberlain, a PhD student at the ACA, have produced what is Bailey says is “perhaps the sharpest image of Mars ever made from the ground.”

But the real gold lies in the spectral data they obtained.

The scientists are applying the same remote-sensing technique that geologists use to map minerals on the Earth’s surface.

Minerals absorb some wavelengths from sunshine and reflect others. Each mineral has its own ‘spectral signature’ – the set of wavelengths it reflects.

“We’re looking particularly for the signatures of minerals, such as hydrated clay minerals, that would indicate the past presence of liquid water,” said Bailey.

Similar prospecting by NASA’s Mars Odyssey spacecraft has shown that there is a vast amount of hydrogen below the surface of Mars. The consensus has been that this is probably water ice.

But did Mars ever have liquid water? And if so, how much? It’s still contentious.

NASA’s Mars Global Surveyor has found sizeable deposits of a mineral called crystalline (grey) hematite, which forms only in the presence of liquid water.

NASA’s two Mars Exploration Rovers, due to land on the Martian surface in January 2004, and the UK lander Beagle 2, due to land in December this year, will also be looking for signs that Mars has had liquid water.

“While spacecraft can get up close, ground-based observations still have a role, as they allow us to use larger and more powerful instruments,” said Bailey.

UKIRT, with a 3.8-m diameter aperture, is the world’s largest telescope devoted specifically to infrared observations.

UKIRT is funded by PPARC, the UK Particle Physics and Astronomy Research Council. The Anglo-Australian Observatory is funded by the UK Government, through PPARC, and the Australian Government.

Observations: Jeremy Bailey (Anglo-Australian Observatory and Australian Centre for Astrobiology, Macquarie University) and Sarah Chamberlain (Australian Centre for Astrobiology, Macquarie University). Data processing: Chris J. Davis, Joint Astronomy Centre, Hawai’i.

Original Source: Joint Astronomy Centre News Release

Image credit: Hubble

NASA’s Hubble Space Telescope snapped this beautiful picture of the Planet Mars when our two planets were only 56 million kilometres apart. The picture was actually assembled from a series of exposures taken between 2220-2312 GMT (6:20 – 7:12 pm EDT) – 11 hours before the moment of opposition. The picture shows many details on the planet’s surface, including impact craters, clouds, and dust storms. The next opportunity for a picture like this will be in 26 months, when our two planets are reasonably close again.

NASA’s Hubble Space Telescope snapped this portrait of Mars within minutes of the planet’s closest approach to Earth in nearly 60,000 years. This image was made from a series of exposures taken between 5:35 a.m. and 6:20 a.m. EDT Aug. 27 with Hubble’s Wide Field and Planetary Camera 2. In this picture, the red planet is 34,647,420 miles (55,757,930 km) from Earth.

This sharp, natural-color view of Mars reveals several prominent Martian features, including the largest volcano in the solar system, Olympus Mons; a system of canyons called Valles Marineris; an immense dark marking called Solis Lacus; and the southern polar ice cap.

Olympus Mons [the oval-shaped feature just above center] is the size of Arizona and three times higher than Mount Everest. The dormant volcano resides in a region called the Tharsis Bulge, which is about the size of the U.S. and home to several extinct volcanoes. The three Tharsis Montes volcanoes are lined up just below Olympus Mons. Faint clouds are hovering over Arsia Mons, the southernmost of these volcanoes.

The long, dark scar, below and to the right of the Tharsis Bulge, is Valles Marineris, a 2,480-mile (4,000-km) system of canyons. Just below Valles Marineris is Solis Lacus, also known as the “Eye of Mars.” The dark features to the left of Solis Lacus are the southern highlands, called Terra Sirenum, a region riddled with impact craters. The diameters of these craters range from 31 to 124 miles (50 to 200 km).

The image was taken during the middle of summer in the Southern Hemisphere. During this season the Sun shines continuously on the southern polar ice cap, causing the cap to shrink in size [bottom of image]. The orange streaks are indications of dust activity over the polar cap. The cap is made of carbon dioxide ice and water ice, but only carbon dioxide ice is seen in this image. The water ice is buried beneath the carbon dioxide ice. It will only be revealed when the cap recedes even more over the next two months. By contrast, the Northern Hemisphere is in the midst of winter. A wave of clouds covers the northern polar ice cap and the surrounding region [top of image].

This view of Mars reveals a striking contrast between the Northern and Southern hemispheres. The Northern Hemisphere is home to volcanoes that may have been active about 1 billion years ago. These volcanoes resurfaced the north’s landscape, perhaps filling in many impact craters. The Southern Hemisphere is pockmarked with ancient impact craters, which appear dark because many are filled with coarser sand-sized particles.

Mars and Earth make a “close encounter” about every 26 months. These periodic encounters are due to the differences in the two planets’ orbits. Earth goes around the Sun twice as fast as Mars, lapping the red planet about every two years. Both planets have elliptical orbits, so their close encounters are not always at the same distance. In its close encounter with Earth in 2001, for example, Mars was about 9 million miles farther away. Because Mars was much closer during this year’s rendezvous, the planet will appeared 23 percent larger in the sky. Mars will not be this close again until 2287.

This photograph is a color composite generated from observations taken with blue, green, and red filters. A total of 11 filters, spanning a wide wavelength range?-from blue to near infrared?-were used during the observations. The shorter wavelengths show clouds and other atmospheric changes. The longer wavelengths, including the near infrared, reveal Martian surface features.

Original Source: Hubble News Release

On Wednesday, August 27 at 0951 GMT (5:51 am EDT) Mars and Earth will be only 56 million kilometres apart; the closest they’ve been in almost 60,000 years. Mars looks best in a telescope, where features like its polar ice cap and dust storms are visible, the planet is easy to spot with the naked eye. Just look to the south in the late evening and you can’t miss it; it currently outshines any other object in the sky other than the Moon. Astronomy clubs and observatories around the world are hosting events to give the public a chance to see the Red Planet – it will remain bright and close for several months.