With her Launch Readiness Review (LRR) milestone upcoming on Monday, 27 July, the way is now clear for NASA’s long-awaited Perseverance rover to begin its voyage to the Red Planet on Thursday, 30 July. Liftoff of the giant United Launch Alliance (ULA) Atlas V rocket—flying in its “541” configuration for the seventh time, equipped with a 17-foot-diameter (5-meter) payload fairing, four solid-fueled boosters and a single-engine Centaur upper stage—is targeted for a two-hour “window” which opens at 7:50 a.m. EDT. The mission will spend 203 days in transit to Mars, before Perseverance commences its Entry, Descent and Landing (EDL) and “Seven Minutes of Terror” on 18 February 2021 to land in the geologically-rich Jezero Crater region, just north of the Martian equator. Although it bears a close similarity to NASA’s in-service Curiosity rover, Perseverance carries a quite different scientific agenda and a different set of tools to enable its explorations, including, for the first time, a helicopter to be flown on another world.
As outlined in AmericaSpace’s three-part look back at past successes, failures and ongoing endeavors on Mars, earlier in July, the United States has a long love affair with the Red Planet, but she has proven to be a mistress notoriously unforgiving of mistakes. Two early Mariner missions suffered launch vehicle failures, the ill-fated Mars Observer was lost shortly before reaching its destination and both Mars Climate Orbiter and Mars Polar Lander failed upon arrival.
Juxtaposed against those losses, America has seen multiple successes: Mariner 4 conducted the first flyby of Mars in July 1965, Mariner 9 became the first spacecraft to enter orbit around Mars in November 1971 and the twin Viking orbiters and landers of the late 1970s began to turn human perceptions of Mars as a “dead” world on its head. More recently, in July 1997 Sojourner became the first roving vehicle to successfully operate on another planet, followed in short order by the Spirit and Opportunity rovers and from August 2012 by Curiosity itself. In May 2008, Phoenix performed the first in-situ exploration of the Martian arctic, whilst a flotilla of others—Mars Odyssey, Mars Reconnaissance Orbiter, the Mars Atmosphere and Volatile Evolution (MAVEN) and InSight—continue to return valuable data from a world which, more than any other, perhaps once closely resembled our own.
The rover today known as “Perseverance” arose following the tremendous early success of Curiosity, which employed a never-before-tried “SkyCrane” to land in the geologically significant Gale Crater, back in August 2012. Shortly afterwards, its mission was extended “indefinitely” by NASA and in December 2012 plans were announced for a “Mars 2020 Rover” to continue a “robust” program of exploration, ahead of human bootprints on the Red Planet in the 2030s.
From the outset, the mission would draw heavily upon the Curiosity design heritage to minimize costs and risks and in January 2013 a 19-member Science Definition Team, chaired by planetary scientist Jack Mustard of Brown University, set to work outlining its research objectives. Six months later, their 154-page report zeroed-in on searching for signs of past life, gathering samples for possible future return to Earth and demonstrating technologies for human missions to Mars. The mission would investigate its landing site “down to microscopic scale” and gather up to 31 samples of rock cores and soil for subsequent return to Earth, as well as demonstrating how to collect carbon dioxide as a potential resource for making oxygen and rocket fuel.
An Announcement of Opportunity for potential instruments was issued in September 2013 and garnered no less than 58 proposals in what NASA said was indicative of “the extraordinary interest in exploration of the Red Planet”. By July 2014, Mars 2020’s $130 million payload of seven instruments had been formally selected.
The Planetary Instrument for X-ray Lithochemistry (PIXL), provided by NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, Calif., sits at the end of Perseverance’s robotic arm and will determine the fine-scale elemental composition of the Martian surface. It reportedly has the capacity to identify chemical elements in targeted spots as small as a grain of salt and will do so very rapidly: spending between a few seconds and two minutes mapping an area the size of a postage stamp on an identified rock or soil specimen.
Norway has provided the Radar Imager for Mars’ Subsurface Experiment (RIMFAX), mounted at the rear of the rover. It will employ ground-penetrating radar to image different densities, structural layers, buried rocks, meteorites and underground water-ice and salty brine to a depth of 33 feet (10 meters). Built by the Norwegian Defence Research Establishment in Kjeller, near Oslo, the acronym also pays tribute to Hrímfaxi, a horse of the night in ancient Norse mythology. RIMFAX will enable Perseverance to image differing surface densities, structural layers, buried rocks, meteorites and the presence of underground water-ice and salty brine. This is expected to yield a unique window into Martian geological and environmental history.
The Mars Environmental Dynamics Analyzer (MEDA), provided by the Spanish Astrobiology Center in Madrid, will provide a set of sensors to measure temperature, wind speed and direction, pressure, relative humidity, radiation and the size and shape of dust particles. MEDA will also contribute to assessments of local Martian weather, as part of ongoing efforts to design In-Situ Resource Utilization (ISRU) technologies for future human exploration missions. As water dominates Earth’s weather, so dust dominates that of Mars, and understanding its behavior is critical if we are to predict meteorological change on the Red Planet. Derived from technologies already deployed on Mars aboard Curiosity and InSight, MEDA will gather data using a battery of sensors on Perseverance’s upright mast and on the body of the rover.
The Mars Oxygen ISRU Experiment (MOXIE) has been jointly devised by the Massachusetts Institute of Technology (MIT) and the Niels Bohr Institute at the University of Copenhagen. It is one of the most exciting of Perseverance’s instruments from a standpoint of developing the means for future human explorers to “live off the land”, in that it will produce a small quantity of pure oxygen from Martian atmospheric carbon dioxide via the process of solid oxide electrolysis. If successful, it is envisaged that MOXIE technology could be used in a significantly scaled-up configuration to produce oxygen for a Mars Ascent Vehicle (MAV) on a future sample-return mission. It is anticipated that MOXIE will produce 0.04 ounces (22 grams) of oxygen per hour over around 50 Martian “sols”—equivalent to about 1,230 hours—with a purity of up to 99.6 percent.
The Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) is an ultraviolet Raman spectrometer which combines fine-scale imaging and an ultraviolet laser to examine minerals and organic compounds on Mars’ surface. Built by JPL, with major subsystems furnished by Malin Space Science Systems and Los Alamos National Laboratory, SHERLOC will assess the “habitability potential” of a sample and its aqueous history, look for the availability of key elements and energy sources needed for life to thrive, determine potential “biosignatures” in rocks and outcrops and provide organic and mineralogical analysis for selective sample caching. Mounted on Perseverance’s robotic arm, SHERLOC will thus be responsible for selecting and storing samples which may someday be returned to Earth for analysis.
Provided by an international collaboration including Los Alamos National Laboratory, France’s Research Institute in Astrophysics and Planetology, the University of Hawaii, the University of Valladolid in Spain and the French Space Agency—the Centre National d’Etudes Spatiales (CNES)—SuperCam is a suite of two lasers and four spectrometers to image and analyze rocks and regolith from a distance, as part of a campaign to identify traces of biosignatures of ancient microbial life.
And MastCam-Z, provided by Arizona State University, consists of a multispectral, stereoscopic imaging instrument to characterize Mars’ landscape geomorphology and processes, assess current atmospheric and astronomical conditions and provide operational support as Perseverance traverses the surface. Its twin zoom cameras, like SuperCam, are mounted on the rover’s remote-sensing mast. All told, this new robotic explorer for Mars boasts no fewer than 23 cameras.
Many of these instruments are based in design on those previously used by Curiosity. Others are wholly new in scope. But one total novelty is the presence of the first helicopter ever to be deployed on an alien world. Dubbed “Ingenuity”, it will scout ahead of Perseverance’s ground-track, perhaps as often as once per day, and was first considered for the mission back in early 2015, as a means of aiding navigation. Envisaged to measure about 3.6 feet (1.1 meters) between blade-tips, the helicopter would check out the best spots to collect soil samples and rocks for a “cache” which a next-generation robotic explorer could pick up for return to Earth.
And although Ingenuity will only fly at altitudes of between 6.6 feet (3 meters) and 30 feet (10 meters) above the Martian surface, on a planet whose atmosphere is barely one-hundredth as dense as our own this is comparable to a height on Earth of 100,000 feet (30,500 meters). That is about seven times higher than terrestrial helicopters can reach. That reality demanded that the helicopter be as light as possible and Ingenuity tips the scales at only 4 pounds (1.8 kg). On each of its short flights, Ingenuity will travel as far as 980 feet (300 meters) and can remain airborne for up to 90 seconds at a time. Formally approved to fly on the mission in May 2018, it was noted that the United States would be first to fly a heavier-than-air craft on another planet. Shortly after Perseverance arrives on Mars, Ingenuity will be put through a 30-day test campaign, involving as many as five airborne sorties with incrementally farther flight distances.
The helicopter has been described by NASA as a “high-risk, high-reward” undertaking, which carries enormous promise for the future exploration of the Red Planet. But Perseverance itself remains highly risky, despite many of its technologies—including the SkyCrane—having already been trialed by its predecessor, Curiosity. With almost half of all missions to Mars having succumbed to failure, nothing can be taken for granted. In tomorrow’s article, AmericaSpace will look at the extensive campaign to build and test this new robotic set of eyes, ears and hands which the United States will soon bring to bear on this mysterious world.
The second part of this article will appear tomorrow.