Марсоход Opportunity: История Исследований Красной Планеты

NASA Mars rover deployed in 2004

Opportunity, also known as MER B (Mars Exploration Rover – B) or MER 1, is a robotic rover that was active on Mars from 2004 until 2018. the rover had traveled a distance of
Due to the planetary 2018 dust storm on Mars, Opportunity ceased communications on June 10 and entered hibernation on June 12, 2018. It was hoped it would reboot once the weather cleared, but it did not, suggesting either a catastrophic failure or that a layer of dust had covered its solar panels. NASA hoped to re establish contact with the rover, citing a recurring windy period which was forecast for November 2018 to January 2019, that could potentially clean off its solar panels. On February 13, 2019, NASA officials declared that the Opportunity mission was complete, after the spacecraft had failed to respond to over 1,000 signals sent since August 2018.

Opportunity and Spirit rovers were part of the Mars Exploration Rover program in the long term Mars Exploration Program. The Mars Exploration Program's four principal goals were to determine if the potential for life exists on Mars (in particular, whether recoverable water may be found on Mars), to characterize the Mars climate and its geology, and then to prepare for a potential human mission to Mars. The Mars Exploration Rovers were to travel across the Martian surface and perform periodic geologic analyses to determine if water ever existed on Mars as well as the types of minerals available, as well as to corroborate data taken by the Mars Reconnaissance Orbiter (MRO). Both rovers were designed with an expected 90 sols (92 Earth days) lifetime, but each lasted much longer than expected. Spirit mission lasted 20 times longer than its expected lifetime, and its mission was declared ended on May 25, 2011, after it got stuck in soft sand and expended its power reserves trying to free itself. Opportunity lasted 55 times longer than its 90 sol planned lifetime, operating for 5498 days from landing to mission end. An archive of weekly updates on the rover's status can be found at the Opportunity Update Archive. On January 25, 2004 (GMT) (January 24, 2004, PST), the airbag protected landing craft settled onto the surface of Mars in the Eagle crater. From its initial landing into an impact crater amidst an otherwise generally flat plain, Opportunity successfully investigated regolith and rock samples and took panoramic photos of its landing site. Its sampling allowed NASA scientists to make hypotheses concerning the presence of hematite and past presence of water on the surface of Mars. Following this, it was directed to travel across the surface of Mars to investigate another crater site, Endurance crater, which it explored from June to December 2004. Subsequently, Opportunity examined the impact site of its own heat shield and discovered an intact meteorite, now known as Heat Shield Rock, on the surface of Mars. Opportunity was directed to proceed in a southerly direction to Erebus crater, a large, shallow, partially buried crater and a stopover on the way south towards Victoria crater, between October 2005 and March 2006. It experienced some mechanical problems with its robotic arm. In late September 2006, Opportunity reached Victoria crater and explored along the rim in a clockwise direction. In June 2007 it returned to Duck Bay, its original arrival point at Victoria crater; in September 2007 it entered the crater to begin a detailed study. In August 2008, Opportunity left Victoria crater for Endeavour crater, which it reached on August 9, 2011. Since January 2013, the solar array dust factor (one of the determinants of solar power production) varied from a relatively dusty 0.467 on December 5, 2013 (sol 3507), to a relatively clean 0.964 on May 13, 2014 (sol 3662). amnesia events continued to occur, however, which eventually resulted in vehicle resets. In light of this, on Sol 4027 (May 23, 2015), the rover was configured to operate in RAM only mode, completely avoiding the use of non volatile memory for storage.

In early June 2018, a large planetary scale dust storm developed, and within a few days the rover's solar panels were not generating enough power to maintain communications, with the last contact on June 10, 2018. but the rover kept silent even after the storm ended in early October, The team remained hopeful that a windy period between November 2018 and January 2019 might clear the dust from its solar panels, as had happened before. On February 12, 2019, past and present members of the mission team gathered in the Jet Propulsion Laboratory (JPL)'s Space Flight Operations Facility to watch final commands being transmitted to Opportunity via the dish of the Goldstone Deep Space Communications Complex in California. Following 25 minutes of transmission of the final 4 sets of commands, communication attempts with the rover were handed off to Canberra, Australia. More than 835 recovery commands were transmitted since losing signal in June 2018 to the end of January 2019 with over 1000 recovery commands transmitted before February 13, 2019. NASA officials held a press conference on February 13 to declare an official end to the mission. NASA associate administrator Thomas Zurbuchen said, "It is therefore that I am standing here with a deep sense of appreciation and gratitude that I declare the Opportunity mission is complete." As NASA ended their attempts to contact the rover, the last data sent was the song "I'll Be Seeing You" performed by Billie Holiday. Assets that had been needed to support Opportunity were transitioned to support the Mars rovers Curiosity and Perseverance.

Opportunity (and its twin, Spirit) are six wheeled, solar powered robots standing high, wide and long and weighing Six wheels on a rocker bogie system enabled mobility over rough terrain. Each wheel had its own motor. The vehicle was steered at front and rear and was designed to operate safely at tilts of up to 30 degrees. The maximum speed was ; , although the average speed was about Both Spirit and Opportunity have pieces of the fallen World Trade Center's metal on them that were "turned into shields to protect cables on the drilling mechanisms". Solar arrays generated about 140 watts for up to fourteen hours per sol, while rechargeable lithium ion batteries stored energy for use at night. Opportunitys onboard computer uses a 20 MHz RAD6000 CPU with 128 MB of DRAM and 3 MB of EEPROM. The rover's operating temperature ranges from and radioisotope heaters provide a base level of heating, assisted by electrical heaters when necessary. Communications depended on an omnidirectional low gain antenna communicating at a low data rate and a steerable high gain antenna, both in direct contact with Earth. A low gain antenna was also used to relay data to spacecraft orbiting Mars.

Archive of MER progress reports by A. J. S. Rayl at planetary. org