Judging from the initial landing, it accidentally landed in a crater, otherwise it was expected to land on a plain. Opportunity successfully studied soil and rock samples and took panoramic photos at the landing site. The samples it collected enabled NASA scientists to put forward hypotheses about the existence of hematite and the existence of water on the surface in the past. To prove this, Opportunity crossed the surface of Mars to investigate another location-Endurance Crater; The survey was conducted from June 2004 to June 65+February 2004. Subsequently, Opportunity investigated the impact site of its abandoned heat shield during the landing and found a complete meteorite, which was later named as the heat shield rock.
From the end of April 2005 to the beginning of June of that year, several wheels of opportunity were dangerously stuck in the sand dunes. Physical simulation has been carried out on the earth for more than 6 weeks to find the best way to take it out of the sand to avoid permanent jamming and scrapping. Later, after it moved a few centimeters, it successfully got out of trouble and continued its journey.
From June 5438+00, 2005 to March 2006, Opportunity headed for Victoria Crater in the south, passing through a large, shallow and partially covered crater-Erebus Crater. Later, I also encountered the problem of mechanical arm. At the end of September, 2006, Opportunity arrived at Victoria Crater, and explored clockwise along the edge of the crater. In June 2007, Opportunity returned to Duck Bay, where the impact crater first arrived. In September of the same year, it entered the impact crater and began detailed research. In August 2008, Opportunity left Victoria Crater and is now heading for Endeavour Crater.
As of 20 13,16 (3,309 days), the mileage of Opportunity was 35.76 kilometers (22.22 miles), which also broke the record of NASA's unmanned probe vehicle's activities outside the earth. On March 22, 2006 (the 760th mission day), Opportunity left the dark crater and began its journey to Victoria crater. It will stay in Victoria Crater until August 2008 (mission days 1630~ 1634).
Victoria Crater is an impact crater about 7 kilometers from the landing site. Its diameter is six times larger than the endurance crater. Scientists believe that if the rover can survive long enough to investigate, the rocks exposed on the wall of Victoria crater can provide more information about the geological history of Mars.
On the 95 1 mission day (September 26th, 2006), Opportunity reached the edge of Victoria Crater and sent the first real photo of Victoria Crater, including the sand dunes at the bottom of the crater. The Mars Reconnaissance Orbiter also took photos of Opportunity in the pothole. On June 4th, 2007, both Opportunity and Spirit received the new flight software of the on-board computer. This update coincides with the third anniversary of their landing. The new system allows the rover to decide whether to send photos or use robotic arms to study rocks, which can save scientists a lot of time without having to filter hundreds of photos to find the one they want, or study the surrounding environment to decide whether to use robotic arms to investigate rocks.
1 15 1 A series of clean-up activities were started on the mission day (April 20, 2007), and the solar power generation of Opportunity was increased to 800 watts per day and hour, until the mission day (May 4, 2007). Solar panels on vehicles can be produced by 65438. In any case, the large-scale sandstorm on Mars in mid-2007 (the global sandstorm cycle every six earth years coaxial with Mars) reduced the power generation of Opportunity to 280 watts per hour.
At the end of June 2007. A series of sandstorms began to cover the atmosphere of Mars. The storm continued to intensify. On July 20th, both Opportunity and Spirit encountered the possibility of real system failure due to insufficient solar energy. NASA released an official statement (excerpt) to the media: We are trying to make the rovers survive the storm, but they are not designed for such a powerful situation. The key problem is that there is too much sand in the Martian atmosphere, which blocks 99% of the sunlight from directly reaching the Mars vehicle. The spirit of the rover in another place can only get a little more light than the opportunity.
Under normal circumstances, solar arrays can generate 700 watts of energy every day and hour. In the sandstorm, the power generation capacity is greatly reduced. If the rover generates less than 150 watts per hour every day, it will start to run out of battery power. If the battery is exhausted, key electronic instruments may fail due to extreme cold. On July 18, 2007, the solar power generation of the rover can only generate 128 watts per hour, which is the lowest point in the mission history. NASA responded by ordering Opportunity to contact the Earth once every three days, which is the first time in its mission history.
When the sandstorm lasted until the end of July, NASA announced that even in very low power mode, the rover had almost no enough energy to survive. If the temperature of the electronic module of Opportunity continues to drop, according to the official statement, Opportunity is at great risk of low power failure. When a low-power fault occurs, the system of the rover will turn off the battery, let the rover sleep, check whether there is enough light energy to wake the rover, and conduct daily fault communication on each mission day. Without enough energy, opportunities will continue to sleep. Depending on the weather, Opportunity can sleep for days, weeks or even months. It depends on whether it can get enough light to try to make its battery-charged rover never wake up from a low-power failure. At that time, it was very possible.
On August 7, 2007, the sandstorm showed signs of weakening. Although the power generation level was still low, it was enough for Opportunity to start shooting and send back photos. On August 2 1 day, the amount of sand in the sandstorm continued to increase, but the battery on the car was fully charged for the first time since the sandstorm began.
On September 1 1, 2007, Opportunity took a little time to sail into Duck Bay and repeatedly sailed out to test the slope friction when it first entered Victoria Crater. On September 13 of the same year, Opportunity began a more complete exploration of the inner slope, and investigated a series of gray-white rock formations in the north of Yawan and the details of Cape Verde's facade. From August 24 to 28, 2008 (mission days 1630 to 1634), Opportunity left the Victoria Crater after experiencing a spike accident caused by Gemini spirit. On its way to the hard impact crater, Opportunity will study a series of dark pebbles on the meridian plateau.
Endeavour Crater is located in the southeast of Victoria Crater, 12 km, with a diameter of 22 km (13.7 miles). It is estimated that this journey will take two years to reach. Scientists hope to find more rocks in this crater than Victoria crater. The phyllosilicate clay-bearing rock found at the edge of hard impact crater is considered to have the shape of bare rock, which is more suitable for life than previous analysis.
The phenomenon of solar harmony is that the earth and Mars move to relative positions with the sun as the center, when the sun is between the earth and Mars. This phenomenon began on June 29th, 2008 +065438+ and caused the communication between the rover and the earth to be interrupted, and it didn't resume until June 65438+February 65438+March of the same year. In the meantime, the control team plans to let Opportunity use Mossbauer spectrometer to study a bare rock named santorini.
On June 29th, 2009, 65438+ was photographed by the high-resolution Surveying and Mapping Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter. The circle on the way represents the position of Opportunity, which is 0/7 km (10.6 mile) away from the hard impact crater. On March 7th, 2009 (mission day 1820), Opportunity left Victoria Crater in August, 2008, walked about 3.2 kilometers (2 miles), and now it has reached the edge of the crater. It also observed the Iazu crater about 38 kilometers (24 miles) away and estimated its diameter to be 7 kilometers (4 miles).
On April 7th, 2009 (mission day 1850), the power supply of Opportunity increased by 40% to 5 15w per hour due to the accidental removal of dust on the solar panel. From April/KOOC-0/6 to April 22 (mission day/KOOC-0/859 to/KOOC-0/865), Opportunity made several trips, and walked a total of 478 meters (/KOOC-0/568 feet) in that week. When Opportunity was studying a bare rock named Penrhyn, the drive actuator of the right front wheel was reset at this time, which made the motor very close to the normal state. On October 28th, 20 10/0 (the 2nd138th mission day), Opportunity arrived at Concepcion crater. Before going to the hard impact crater, it successfully bypassed the impact crater with a diameter of 10 meter. During this period, the power supply dropped from 305 watts per hour to 270 watts per hour.
On May 5, 20 10, the route between Victoria Crater and Endeavour Crater may have dangerous sand dunes, so the original route was changed and extended to 19 km.
On May 9, 20 10, Opportunity experienced 2,246 mission days, surpassing the record of 2,245 mission days of Viking 1 and becoming the longest mission on the surface of Mars in history.
20 10 In July, the research team of Opportunity announced that Captain james cook, who had led the hard fleet to cruise in 1769~ 177 1 Pacific Ocean, would be informally named as a hard collision pit. These include Tribulus Horn, Camel Horn, Byron Horn (the earliest named place in Australia) and Hicks Horn (the first Australian place seen by the Endeavour fleet at 1770).
On September 8, 20 10, NASA announced that Opportunity had reached the halfway point between Victoria Crater and Endeavour Crater.
In June165438+1October of the same year, Opportunity spent several days shooting a 20-meter-long crater called Brave. 20 10, 165438+ 10 month, 14 (the 2420th mission day), Opportunity reached the mileage record of 25 kilometers. At this time, it is about 1.5 kilometers away from Santa Maria crater, and it takes 6.5 kilometers to reach the hard impact crater. In June 5438+ 10 and June 5438+065438+ 10, the solar power supply was about 600 watts/hour.
By 20 10, 12, 10, Opportunity has traveled more than 26 kilometers on the surface of Mars since it landed on June 25, 2004. On 20 10, 12, 15 (the 2450th mission day), Opportunity arrived at Santa Maria Crater, and the control team planned to let it explore this 90m-wide crater (about the size of an American football field) in the next few weeks. On Friday, scientists described NASA's rover Opportunity as limping and suffering from arthritis, but Opportunity discovered this after going to the red planet for about 10 years.
This unmanned solar rover has just completed the analysis of the oldest rock it has acquired. This rock is named "Hope" 6, which contains a lot of evidence that water that may be suitable for life once flowed on Mars, leaving clay minerals in the rock.
Steve squyres, principal researcher at Cornell University, said: "This is strong evidence that water once interacted with this rock, changing its chemical structure and significantly changing its mineralogical composition."
He called this research "almost the most important" achievement since the beginning of the "Opportunity" exploration 10, because the chemical process it showed was completely different from most previous discoveries about the existence of water on Mars. Mars is very dry.
Scientists believe that a large amount of water once flowed through the rocks of Mars and through the cracks in the rocks, leaving a very high concentration of clay in the rocks. Squyres said that the analysis showed traces of water that might be suitable for drinking, dating back to the first 654.38 billion years in the history of Mars, when clay rocks were formed in a more neutral pH environment, and then the environment became worse and the water became more acidic.
The rock polishing tool, alpha particle X-ray spectrometer and microscope imager carried by Opportunity provide details for scientists on Earth, so that they can understand the history of Mars without bringing rocks back to Earth.
Opportunity and its twin brother Spirit were launched in 2003 and landed on Mars in June 5438+the following year 10. The original plan was to let them explore for three months. Both probes found evidence of the humid environment of ancient Mars. When introducing the main differences in the composition of the stone of hope, squyres told the reporter: "Most of the evidence found by Opportunity before is sulfur-containing sulfonic acid. This time, we found drinking water. In the past, the biggest discovery of Opportunity on Mars was that it stood on an ancient coastline. It found that there is a warm and humid salty liquid ocean on Mars. This discovery was also rated as the biggest scientific breakthrough in 2004 by Science magazine.
Opportunity's first clue was gray hematite. Gray hematite is actually a kind of rust. Most of the iron on the earth sank into the center of the earth at the early stage of its formation. However, because the mass of Mars is much smaller than that of the earth, a large amount of iron remains on the surface, which provides raw materials for the formation of gray hematite. Gray hematite widely exists on the earth. It is usually found in still water and hot springs, and sometimes volcanic activity also brings gray hematite. Therefore, the existence of gray hematite means that liquid water is likely to exist.
Later, Opportunity discovered four other evidences through the analysis of Martian rocks, which strongly suggested that there was a liquid ocean on Mars. Opportunity found spherical objects with a diameter of several centimeters in and around rocks, and their chemical composition is different from that of rocks, which should be solidified from substances in liquid water; Opportunity's photos show that there are some flat holes in the rock, which should be left over from the decomposition of crystals in water; Opportunity's spectrometer detected a lot of sulfur in rocks, which can only come from sulfate formed in water environment; Another Opportunity spectrometer discovered jarosite, a rare substance that usually forms in water.
Shortly after Opportunity discovered the Martian ocean, Spirit also found traces of liquid water on the other side of Mars, but there seems to be much less water there. In March 2007, Opportunity was lucky enough to witness the "solar eclipse" on Mars for the first time. Perhaps saying "solar eclipse" here will cause misunderstanding, because the "solar eclipse" on Mars is really far from the solar eclipse on our earth, but there is no better title to use.
Mars has two natural satellites, both of which are much smaller than the moon, or they are like two huge stones with irregular shapes. One of them is equivalent to a diameter of 23 kilometers, and the other is only equivalent to 13 kilometers. In view, the two satellites are just two small black spots, so when the so-called Mars solar eclipse occurs, only two small black spots pass through the sun, just like two moving sunspots.
The eclipse seen by Opportunity was caused by Phobos. The duration is very short, only more than 20 seconds. This is also a feature of the solar eclipse on Mars. The eclipse caused by Phobos lasts about 30 seconds, and Phobos is longer, up to 3 minutes. In contrast, the total solar eclipse on the earth usually lasts for a few minutes, but it will not exceed 8 minutes.
Found rocks formed in acidic lakes
When Opportunity landed on the meridian plain on the surface of Mars, it found a turning point. It found that the rocks at the landing site were formed in an ancient acidic lake, and the evidence came from hematite, which is generally formed in water and formed in a tiny spherical particle similar to blueberries. This unique curvilinear deposit is formed by gentle water scouring. When salt water evaporates, sulfate precipitates, and finally this rock structure is formed.
The first discovery of meteorites on Mars
June 5438+October 2005 10, Opportunity found an unusual metal-like rock near its abandoned heat shield. The spectrometer carried on the detector confirmed that the rock is composed of iron and nickel, indicating that it may be a meteorite from space. This is the first time that man has found meteorites on an alien planet.
Dune of purgatory
In April, 2005, Opportunity got stuck in a shallow sand ridge, and finally it took five weeks to get rid of the 30cm thick sand ridge. This kind of corrugated sand is named "purgatory sand dune".
Arrive at Victoria crater
In September 2006, Opportunity traveled 9 kilometers from the landing site Eagle Crater to Victoria Crater with a diameter of 800 meters, which is 40 times that of Eagle Crater. This crater was studied for six months in 2004. After a year's investigation and detection of sandstorms around Victoria crater, Opportunity began to enter this crater in September 2007. The crater formed by this meteorite collision is 30 meters deep, which is six times the depth of the crater previously surveyed by Opportunity. More importantly, Victoria Crater will witness the whole life course of Meridian Plateau. This crater is covered with sulfate sandstone and is thought to have been formed billions of years ago. At that time, sand dunes interacted with water, which probably came from shallow lakes and then connected and strengthened to form solid rocks. Ray Arvidson, a Mars probe scientist, said: "This environment confirms that the existence of ancient Mars lakes is regional, not indigenous."
In August, 2008, Opportunity trudged forward in Victoria Crater and began to move forward to a crater with many caves. This crater is called Endeavour, and its area is 20 times that of Victoria Crater.
Found a huge groundwater layer
It still works "healthily" on the surface of this red planet, and celebrated the eighth anniversary of its work on Mars in February 20 12. 20 1 1 In August, after almost three years of trekking, this weather-beaten rover finally reached its dream destination: Endeavour Crater with a diameter of about 22 kilometers. Opportunity also found what geologists think is the best evidence that liquid water once flowed on the surface of Mars, and explored the Matijevic Mountains.
For the exploration mission of Mars, many people put their energy into the exploration of Curiosity. In fact, a rover Opportunity, a figure from the earth, has made an exploration plan on this mysterious red planet, and Opportunity is making an exploration plan for the "Ma Thievy Keshan" on Mars. The camera tools on Opportunity have taken images overlooking Mount Matijevic. The entire "Matijevic Mountain" is 14 mile wide, and there is also a crater called Endeavour. This rover has traveled nearly 22 miles, and the rocks here are also rich in iron.
Ma Thievy Keshan's microspheres have different compositions and internal structures. Opportunity's scientific team is evaluating the composition of rock elements in this area and how these spheroids are formed. The diameter of each sphere is about 3 mm wide.
Opportunity found that there are hydrated minerals in the nodules of these spherical rocks, which is one of the reasons why these rocks form spherical particles. However, this theory is still speculative, and there is no further evidence that the existence of water on Mars led to the formation of these spheres. Another possibility of the formation of these spheres is that the eruption of volcanic ash led to the formation of these spheres. Of course, there are other possibilities.
"At present, we have many hypotheses about the formation of small spheres, all of which are hypothetical studies on the formation and shape of small spheres," said Steve squyres, the principal researcher of Opportunity. "This is very helpful for us to understand the formation of small spheres. We will study our hypothetical possibilities in the next few months and propose the most likely reasons for the formation of small spheres. " According to foreign media reports, NASA's "Opportunity" rover, which has been out of service, is slightly better than the "Curiosity" rover, and now a clay deposit containing water has been discovered. This proves that the clay layer that forms water on the surface of Mars far exceeds the previous scientists' prediction.
The research results were obtained by locating and analyzing the chemical composition of Opportunity in the Mars orbiter mission. 20 1 1 In August, the rover Opportunity reached Endeavour Crater after extending its service life 1000 days and crossing the meridian plain for 20 kilometers. The results of chemical investigation show that there are many kinds of clay here, which is helpful to the formation of water on the earth.
It is reported that the rover Opportunity and Spirit landed on the surface of Mars in June 5438 +2004 10, and they were responsible for surveying and looking for evidence of water resources in the history of Mars. These two rovers played an important role in mastering water resources in ancient Mars, but the chemical properties of Martian liquid were determined to be strongly acidic, similar to battery electrolyte, which was not suitable for our known life.
Steve squyres, the scientist in charge of this research, said at the American Geophysical Congress held in San Francisco, USA that clay minerals are closely related to the chemical properties of neutral water resources, and neutral water is potable water.
If the service period of the rover Opportunity can be extended, scientists will hopefully make more important discoveries. The Mars Compact Sky Survey Imaging Spectrometer (CRISM) of Mars Orbiter found that the edge and interior of Endeavour Crater contain more types of clay minerals, which are far richer than the two kinds of clay claimed in previous reports.
Associate Professor James Rey, a planetary scientist at Georgia Institute of Technology, said that if the rover Opportunity can find samples of Martian clay and let us observe and analyze them closely, we can determine how these clays were formed, so as to determine whether they were formed in deep-water lakes, shallow ponds or volcanic eruptions.
Further exploration and analysis data of Martian clay are expected to come from Curiosity Rover. On August 6, 2003, the rover landed in a huge crater with a 4.8-kilometer-high layered sedimentary plateau at the bottom. Unlike the rover Opportunity, Curiosity is equipped with a complex airborne chemistry laboratory, which can be used to analyze rock and soil samples. Two important scientific instruments of Opportunity are no longer working properly. This research report was published in Geophysical Research Letters,
This is also the first 10 year that Opportunity greeted it on the surface of Mars. Opportunity landed on June 24, 2004. Its original goal was to find clues on the surface of Mars whether water ever existed. This was originally a three-month mission, but it has continued to this day, and the running time of Opportunity has been 36 times that of the original plan.
Since landing on Mars, Opportunity has traveled 22.03 miles (more than 35,000 meters), further than its target of 2,000 feet (609.2 meters). In the first three months, NASA scientists were full of excitement because Opportunity provided evidence that water once flowed on the surface of Mars at some time in the past. These days, Opportunity has been busy between craters, trying to observe the surface of Mars more deeply.
The spirit of Opportunity is touching, but we bet that NASA will continue to get more scientific investigations from Opportunity.