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What Is The Thesis Statement Of The Research Report Life On Mars?

Many students look for an excellent way to start a research paper on life on mars. However, to write a good thesis statement on the topic, a student must understand what a thesis statement is and its importance. This article aims to enlighten you on how to write a great thesis statement and give you some suggestions on thesis statements ideas you can use for your upcoming essay. But first: a thesis statement appears in the introductory paragraph and presents the essay’s main topic. In your life on mars paper, the thesis statement should introduce the reader to what you’ll be talking about. Your thesis statement is the most crucial part of an essay because it also sets the tone for the rest of the paper.

What Can You Write About in Your Life on Mars Thesis?

How to start thesis statement of the research report life on mars, why introduction to research report on life on mars matters, topics to write in your life on mars research paper thesis statement, let’s help you write the best life on mars thesis statements and papers.

There are three approaches you can use to write a thesis statement about life on Mars. They include giving detailed explanations, arguing your facts, and analyzing the topic. Here’s more to that:

• Explanatory thesis statement: This is where the writer gives a detailed account of a particular topic on life on mars. It requires you to be accurate on facts you write down and present evidence. These thesis statements do not support or oppose any claim.
• Argumentative thesis statement: Such a thesis statement requires you to express a specific view on life on Mars. After that, back or oppose your idea while supporting your stand. You need plenty of research to back your opinion. An example is ‘There can be no life on Mars.’
• Analytical thesis statement: It requires analysis of a particular topic, defining it, noting its various features, and evaluating it. Such thesis statements are suitable for writing papers where data analysis dominates.

An introduction to a research report done correctly will help you structure your argumentative, analytical or explanatory essay . Here are the steps to follow when writing your thesis statement on the research report on life on Mars:

• Conceptualize your thesis statement. It’s always a good idea to brainstorm and have the statement ready before writing. Have the relevant research to help you develop the body of your essay. In this case, read about life on Mars from several materials to establish points to write about.
• Answer a certain question. Your thesis statement should be an answer to a specific question. It should inform the reader what you’ll be writing about. For instance, a thesis statement such as ‘How life on mars negatively affects human life’ tells the reader that you intend to write about the adverse effects of mars on human life.
• Go straight to the point. A good thesis statement should be brief. While a couple of sentences may be acceptable, you should express your point in one sentence. For instance, an ideal thesis statement would be’ Human life on Mars is not possible.’

The introduction of any research report informs the reader of the paper’s contents. It gives some information on the subject that will be discussed. An excellent example of an introduction ought to:

• Provide the reader with background information about Mars.
• Talk about features of Mars similar to other planets like Earth.
• Briefly explain what you intend to write.

Are you figuring out what to write? The following are some examples regarding life on Mars that you can use as inspiration in your paper:

• How life on Mars would positively influence human life
• Analysis of the future possibilities of life on Mars
• Mars has the potential to support human life
• Evidence supporting the hypothesis of life on Mars

Feel free to reach out and learn more about thesis statements and relevant information to help you write a thesis. More so, we’ll write a variety of papers, from essays, homework, assignments, to dissertations, and guarantee quality essays with thesis statements that stand out.

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Writing Life on Mars: Posthuman Imaginaries of Extraterrestrial Colonization and the NASA Mars Rover Missions

• First Online: 01 January 2022

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• Jens Temmen 6  

Part of the book series: Palgrave Studies in Life Writing ((PSLW))

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Focusing on three different life narratives and practices of Mars colonization—the NASA rover missions, the technoliberal campaign to settle the red planet by space entrepreneur Elon Musk, and the critical activist project “Planetary Personhood”—Jens Temmen analyzes how, in the context of climate change debates, human colonization of other planets has been reframed as inevitable and necessary to ensure the survival of humanity. Temmen’s contribution focuses on how these “astrofuturist” narratives negotiate the utopian vision of space colonization as a transformative posthuman experience of escape from the terrestrial limits placed on humanity, and it discusses whether life writing as a format allows for a thorough and critical posthuman inquiry of humanity’s anthropocentrism.

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Scorched Earth: Discourses of Multiplanetarity, Climate Change, and Martian Terraforming in Finch and Once Upon a Time I Lived on Mars .

The Universe Decentered: Transcultural Perspectives on Astrobiology and Big History

Missions and Explorers: “Amundsen” as a Key to Reading Alice Munro’s Other Stories

Ganser, “Astrofuturism,” 36.

Ibid., 35, 37.

See Ganser, “Astrofuturism,” 36, 40. See Kilgore, “Astrofuturism,” 1, quoted in Ganser, “Astrofuturism,” 35.

Davenport, The Space Barons , 4, 123, 143–144.

See Ganser, “Astrofuturism,” 37, 40. See Redmond, “The Whiteness of Cinematic,” 348.

See Braidotti, The Posthuman , 9.

See Messeri, Placing Outer Space , 2.

See Vertesi, Seeing Like a Rover , 20.

Similar to the idea of “greenwashing” products as environmental-friendly, the concept of “double red washing” refers to how the privatization of the space industry is promoted by Musk and others as the only way to achieve the colonization of the red planet, and to how both the privatized space industry and Mars colonization are depicted as progressive measures aiming for greater social justice (see Marx, “Elon Musk is Planning”).

See Braidotti, The Posthuman , 43–44.

Opportunity’s sister rover “Spirit” had shut down in 2009 already.

See “‘My battery is low.’”

See Simon, “Opinion.”

See Butler, “Precariousness and Grievability.”

Butler analyzes how in times of war and crisis, the notion of a grievable death is a political issue of enormous significance. Focusing on 9/11 and the subsequent war in Iraq, Butler describes how public mourning can be used as a way of supporting the war effort and of constructing nationalist (non-)belonging, but also as a mode of dehumanization of the lives that are specifically constructed as ungrievable. Even though Butler’s work is deeply immersed in the specific context of warfare, her assumptions are valid for the way in which the rovers and their demise figure as a ledger for nationalistic sentiments of belonging and pride.

The playlist consists of the music that NASA staffers had sent to Opportunity along with its wake-up command after the storm had crippled him and includes songs such as David Bowie’s “Life on Mars?,” “Staying Alive” by the BeeGees, as well as Wham!‘s “Wake Me up Before You Go-Go.”

Simon, “Opinion.”

See Messeri, Placing Outer Space , 19.

Messeri, Placing Outer Space , 19.

See Messeri, Placing Outer Space , 5, 19, 34.

Braidotti, The Posthuman , 2.

Vertesi, Seeing Like a Rover , 20.

See Atanasoski and Vora, “Why the Sex Robot,” 2.

The way that the rovers seem to break barriers between technology, human, and animal, make them comparable to other posthuman icons, such as the cloned sheep Dolly, which, according to Braidotti, is an entity “no longer an animal but not yet fully a machine,” 74. The rovers, no longer a machine but not yet fully human, seem to be on that same spectrum.

Atanasoski and Vora, “Why the Sex Robot,” 6. See Markley, Dying Planet , 270.

Braidotti, The Posthuman , 43–44.

See Vertesi, Seeing Like a Rover , 7, 170–171.

Vertesi, Seeing Like a Rover , 25.

Ibid., 171.

Ibid., 176.

Keeling, “Queer OS,” 157.

See Braidotti, The Posthuman , 9, 124, 125–126. See Mbembe, Necropolitics .

Atanasoski and Vora, “Why the Sex Robot,” 1, 6. Atanasoski and Vora’s work focuses predominately on self-reproducing robots which are projected to be a vital part of the first steps to Martian colonization, but which have not yet been constructed or deployed (see ibid., 2). The way that NASA frames the current Mars rovers as links in human evolution, allows, I would argue, for a broadening of Atanasoski and Vora’s argument to apply here as well.

See Messeri, Placing Outer Space , 18, 68.

See Messeri, Placing Outer Space , 18. See Vertesi, Seeing Like a Rover , 31–32. A prominent and striking example is the influential essay by aerospace engineer Robert Zubrin, titled “The Significance of the Martian Frontier,” which advocates for Martian colonization through frontier discourses in general and by directly drawing on Frederick Jackson Turner’s infamous frontier thesis in particular, 13.

The concept of terra nullius is a core tenet of settler colonialism that relies on framing the Indigenous populations of newly “discovered” lands as less-than-human and therefore without claim to their own land (see Robertson, Conquest by Law ).

Atanasoski and Vora, “Why the Sex Robot,” 2.

See Temmen, “From HI-SEAS to Outer Space.”

See Saraf, “‘We’d Rather Eat Rocks.’”

See Messeri, Placing Outer Space , 68.

Atanasoski and Vora, “Why the Sex Robot,” 6.

Even though space agencies around the globe rely (and have relied for a long time) on private industry contractors, space travel is not a privatized business, but regulated on a national and international level. Private businesses can partner with national agencies, but they cannot conduct space travel on their own. While Musk and others have become important players as contractors, their vision includes completely privatizing space travel, which would, in their perspective, break a detrimental nation-state monopoly on space travel.

Davenport, The Space Barons , 4.

Ibid., 4–5.

See Wallace-Wells, The Uninhabitable Earth , 175–176.

Messeri, Placing Outer Space , 18.

Atanasoski and Vora, “Why the Sex Robot,” 11.

Davenport, The Space Barons , 1–2.

See Davenport, The Space Barons , 2.

Atanasoski and Vora, “Why the Sex Robot,” 1.

See Davenport, The Space Barons , 49–60, 117.

“When Slow Violence Sprints.”

Wallace-Wells, The Uninhabitable Earth , 176.

See Braidotti, The Posthuman , 5–6. See Chakrabarty, “The Climate of History,” 221–222.

See Heise, Sense of Planet , 25. See Atanasoski and Vora, “Why the Sex Robot,” 16.

Nonhuman Nonsense, “Planetary Personhood.”

See New Zealand Parliamentary Counsel Office, “Te Urewera Act 2014.”

See Atanasoski and Vora, “Why the Sex Robot,” 14.

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Temmen, J. (2021). Writing Life on Mars: Posthuman Imaginaries of Extraterrestrial Colonization and the NASA Mars Rover Missions. In: Batzke, I., Espinoza Garrido, L., Hess, L.M. (eds) Life Writing in the Posthuman Anthropocene. Palgrave Studies in Life Writing. Palgrave Macmillan, Cham. https://doi.org/10.1007/978-3-030-77973-3_8

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• Published: 21 February 2023

Life on Mars, can we detect it?

• Carol R. Stoker   ORCID: orcid.org/0000-0001-7265-292X 1  

Nature Communications volume  14 , Article number:  807 ( 2023 ) Cite this article

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• Astrobiology
• Biochemistry

Searching for evidence of life on Mars is a major impetus for exploration. A new study published in Nature Communications finds that current Mars mission instruments lack the essential sensitivity to identify life traces in Chilean desert samples that strongly resemble the martian area currently under study by NASA’s Perseverance rover.

Almost half a century ago the NASA Viking landers searched for evidence of life in Mars soils by attempting to detect active metabolism and measuring organic compounds by heating to vaporize them for detection via Gas Chromatography Mass Spectrometry (GC-MS). When no organic compounds were detected even at levels of parts per billion 1 , this provided a puzzle. Since organic compounds are continuously delivered to Mars by meteorites, comets, and interplanetary dust particles they should be ubiquitous and comprise up to 2% of Mars soil 2 . But where are they? This curious lack of organics argued both against a biological interpretation for results of the metabolism experiments, and for the presence of strong soil oxidants that actively destroy these compounds 3 . However, decades later the Viking GC-MS results were explained by the presence of high levels of perchlorate salts in the Martian soil 4 that oxidized organics during pyrolysis in the Viking GC-MS instrument 5 .

While Viking lander results seemed unpromising for surface life in the cold, dry martian conditions, data from Viking orbiters and later missions showed that Mars had surface liquid water early in its history (3 to 4 billion years ago) 6 where life may have thrived. This led later NASA rover missions to seek evidence of ancient habitable environments hosting organic remnants of life. The SAM ( Sample Analysis on Mars ) instrument on the Curiosity rover detected organics in ancient lakebed deposits 7 , 8 , but they are found at low levels (parts per billion) and appear to be highly altered. The Perseverance rover, now exploring an ancient illuvial fan river delta, has detected aromatic organic compounds using fluorescence spectroscopy 9 . But in these cases, the simple organics detected could have been delivered to Mars from space so proving a biological origin is impossible.

The paper by Azua-Bustos et al. 10 in Nature Communications describes analysis of samples collected from “Red Stone”, an alluvial fan river delta more than 100 million years old in the Atacama Desert of Chile, Earth’s oldest and driest desert. Red Stone has similar geology to the delta area currently being studied by NASA’s Perseverance rover 11 (Fig.  1 ). The Red Stone location (near the ocean) frequently experiences fogs that provide water for sparse but active microbial life that was detected by DNA extraction and gene sequencing, microscopy, and growth of a few microbial strains cultured from the samples. Most microbes identified consist of “microbial dark matter” i.e., genetic information is from organisms that have not yet been described.

a Red Stone deposit from panorama image courtesy of Armando Azua-Bustos. b A section of the panoramic composite image [image PIA24921_MAIN-20k.jpg] of the Jezero delta captured by the MastCam-Z camera on the Perseverance Rover in June 2022 15 (Courtesy NASA/JPL-Caltech/ASU/MSSS). The height of both white scale bars are ~2 m.

Samples from Red Stone were also analyzed by instruments that simulate those used on Mars, but even finding organics in these samples was challenging. A GC-MS instrument comparable to but ten times more sensitive than Curiosity rover’s SAM instrument was barely able to detect specific biogenic organic compounds at the limit of detection, suggesting that SAM could not have detected them. There was more success with organic detection after sample extraction with a powerful solvent that was also implemented on the SAM instrument. Indeed, the SAM instrument detected organics in both sedimentary mudstones and dune sands on Mars by using solvent extraction and derivatization (a chemical treatment to make organic compounds easier to detect) 8 .

Red Stone samples were analyzed with a testbed of the MOMA (Mars Organic Molecular Analysis) instrument 12 planned for the European ExoMars rover payload. No organics were detected when flash pyrolysis was used, but a few organic molecules were identified in evaporite samples when they were first extracted with a solvent and derivatized.

Red Stone samples were also analyzed with the SOLID-LDChip (Signs of Life Detector-Life Detector Chip) 13 , an instrument based on the technology of immunoassay that is commonly used in biomedicine. SOLID was designed for life detection on Mars but no scheduled missions plan to use it. Interestingly, the LDChip detected evidence of cyanobacteria that were not seen in the modern microbiota so Azua-Bustos et al. 10 posit these biosignatures were deposited along with the delta sediments at least 100 million years ago.

This Red Stone sample analysis 10 shows how critical it is to test instruments designed for life detection on other planets by using samples from relevant Earth analogs prior to selecting them for flight missions. If the biosignatures can’t be detected in Earth samples, where both current and ancient life is clearly documented, we should not expect these instruments to be capable of detecting evidence of life from Mars’ early history.

Azua-Bustos et al. 10 argue that detection of ancient life signatures will require sample analysis in sophisticated terrestrial laboratories. This same view has led to the current plans for searching for life: the Perseverance rover is collecting samples that are to be retrieved and brought to Earth by a future mission 14 . But any biological activity in these samples presumably took place billions of years ago, and only a few small samples can be brought to Earth for study. It remains to be seen if unambiguous signatures of life can be found in those limited samples. We must be cautious about interpreting absence of strong evidence of life as evidence of its absence!

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Azua-Bustos, A. et al. Dark microbiome and extremely low organics in an Atacama fossil river delta unveil the limits of life detection on Mars. Nat. Commun. this issue . https://doi.org/10.1038/s41467-023-36172-1 (2023).

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Haltigen, T. et al. Rationale and Proposed Design for a Mars Sample Return (MSR) Science Program. Astrobiology 22 , S27–S55 (2022).

A small segment of a panorama comprised of Perseverance Rover MastCam-Z images (image PIA24921_Main-20k.jpg) taken June 2022. The full panoramic image is available for download at https://mars.nasa.gov/resources/26978/detailed-panorama-of-mars-jezero-crater-delta/ .

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Stoker, C.R. Life on Mars, can we detect it?. Nat Commun 14 , 807 (2023). https://doi.org/10.1038/s41467-023-36176-x

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“Is there life on Mars?” is a question people have asked for more than a century. But in order to finally get the answer, we have to know what to look for and where to go on the planet to look for evidence of past life. With the Perseverance rover set to land on Mars on February 18, 2021, we are finally in a position to know where to go, what to look for, and knowing whether there is, or ever was, life on the Red Planet.

Science fiction aside, we know that there were not ancient civilizations or a population of little green people on Mars. So, what sort of things do we need to look for to know whether there was ever life on Mars? Fortunately, a robust Mars exploration program, including orbiters, landers, and rovers, has enabled detailed mapping of the planet and constrained important information about the environment.

We now know that there were times in the ancient past on Mars when conditions were wetter and at least a little warmer than the fairly inhospitable conditions that are present today. And there were once habitable environments that existed on the surface. For example, the Curiosity rover has shown that more than three billion years ago, Gale crater was the location of a lake  that held water likely suitable for sustaining life. Armed with information about the conditions and chemical environments on the surface, the Perseverance rover is outfitted with a science payload of instruments finely tuned for extracting information related to any biosignatures that might be present and signal the occurrence of life .

Panoramic view of the interior and rim of Gale crater. Image generated from pictures captured by the Curiosity rover.

But where should we go on Mars to maximize the chances of accessing the rocks most likely to have held and preserve any evidence of past life? To get at that answer, I co-led a series of workshops attended by the Mars science community to consider various candidate landing sites and help determine which one had the highest potential for preserving evidence of past life. Using data from Mars orbiters coupled with more detailed information from landers and rovers, we started with around thirty candidate sites and narrowed the list over the course of four workshops and five years. Some sites were clearly less viable than others and were weeded out fairly quickly. But once the discussion focused on a couple of different types of potentially viable sites, the process became much tougher. In the end, the science community felt—and the Perseverance mission and NASA agreed—that Jezero crater was the best place to look for evidence of past life on Mars.

This image shows the remains of an ancient delta in Mars' Jezero Crater, which NASA's Perseverance Mars rover will explore for signs of fossilized microbial life. The image was taken by the High Resolution Stereo Camera aboard the ESA (European Space Agency) Mars Express orbiter. The European Space Operations Centre in Darmstadt, Germany, operates the ESA mission. The High Resolution Stereo Camera was developed by a group with leadership at the Freie Universitat Berlin.

What is so special about Jezero crater and where is it? Jezero crater is ~30 miles (~49 km) across, was formed by the impact of a large meteorite, and is located in the northern hemisphere of Mars (18.38°N 77.58°E) on the western margin of the ancient and much larger Isidis impact basin. But what makes it special relates to events that happened 3.5 billion years ago when water was more active on the surface of Mars than it is today. Ancient rivers on the western side of Jezero breached the crater rim and drained into the crater, forming a river delta and filling the crater with a lake. From the study of river deltas on the Earth, we know that they typically build outwards into lakes as sediment carried by the associated river enters the lake, slows down, and is deposited. As this process continues, the delta builds out over the top of lake beds and can bury and preserve delicate and subtle signatures of past life. These “biosignatures” are what Perseverance will be looking for when it lands on the floor of the crater and explores the ancient lake beds and nearby delta deposits.

Perseverance will use its instruments to look for signs of ancient life in the delta and lake deposits in Jezero crater and will hopefully allow us to finally answer the question of whether there was ever life on Mars. In addition, Perseverance will begin the process of collecting samples that could one day be returned to Earth. The importance of sample return cannot be overstated. Whether or not evidence of past life is found by Perseverance’s instruments, the legacy enabled by samples the rover collects will be the “scientific gift that keeps on giving”. Once returned to Earth by a future mission, these Mars samples can be subjected to more detailed analysis by a much wider set of instruments than can be carried by Perseverance . Moreover, sample archiving can preserve material for future analysis here on Earth by new and/or more detailed instruments that may not yet exist. So even if Perseverance does not find evidence of past life, it will collect samples that, once returned to Earth, could provide new insight into the evolution of Mars and whether there was ever life on the Red Planet.

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Life on Mars and the Imagination of Scientists

Around this time seven years ago I was trying to figure out a topic for my Master’s thesis. It could have been anything at all, so long as it fit under the wide umbrella of science writing. After a few dead ends (sumo wrestling, Amish science) I finally chose to write about the hunt for life on Mars.

My advisor wasn’t keen on the idea, and it was way, way out of my wheelhouse. But I pushed on anyway, for three reasons I can remember. Astrobiology   has only been considered a legitimate scientific endeavor since the ’60s. So every study felt fresh and exciting. It’s also inherently multidisciplinary — requiring geologists, climate scientists, astrophysicists, engineers, DNA experts, microbiologists and even philosophers — which meant my story would have lots of different voices. Perhaps most important, all of those voices are focused on one Big Question: Are we alone in the universe?

For the same reasons, astrobiology is perfect for science education, or so argues a new study in the journal Astrobiology . Researchers from the University of New South Wales, in Sydney, Australia, surveyed high schoolers before and after completing a one-day museum program in which they pretended to be scientists involved in Mars rover missions . The study found that this simulation corrected some of the students’ misperceptions about science and scientists.

These effects, though, were small. Overall the study was quite depressing, especially on one point: Even after completing the program, around two-thirds of the students said they didn’t think that scientists are creative or use their imaginations.

This is a massive problem. And fixing it will take a lot more than flashy rovers and the promise of aliens.

Somebody in the humanities might legitimately ask why I think this is a problem. Some kids like science, some like art, big deal?

Liking science isn’t the issue.   Consider a 2007 survey of 15-year-olds from some 25 countries. The students rated how much they agreed with a bunch of statements about science (from 1, Disagree, to 4, Agree). In every country surveyed, the average rating of “School science is interesting”   was above the neutral score of 2.5. In the new Australian study, too, the teenagers liked science. They were recruited to the study, in fact, because they had signed up for a one-day museum program.

But kids can’t picture themselves doing science for a living. Another statement in that same 2007 survey was, “I would like to become a scientist.” The average rating from developed countries* was around 2 for boys and a dismal 1.5 for girls. Similarly, a 2010 study followed 33 students in California who in 10th grade said they were “very interested” in a science career. By 12th grade, 45 percent had lost interest.

So how come kids who like science don’t want to become scientists? One big reason, according to many studies, is they don’t think it’s a creative job. In-depth interviews with high school and college students (whether from New York , Europe , or   New Zealand ) have revealed that the students often believe that science and creativity are incompatible. Seriously.

This couldn’t be farther from the truth, of course, and that’s the lesson the Australian researchers were hoping to get across with the Mars programs. The researchers surveyed 230 teenagers who participated in one of two museum programs: Pathways to Space at the Powerhouse Museum, in Sydney, and Mission to Mars at the Victorian Space Science Education Centre, in Melbourne. Both programs seem super-fun. In Pathways, students plan a rover mission and then execute it in a “Mars Yard” that looks strikingly like the real thing (which you can see in this short   video ). In Mission to Mars, students role-play being astronauts or mission control engineers, and analyze data picked up by a rover in a simulated martian crater.

The students’ responses perfectly illustrate the broader issues in science education that I outlined above. Before the one-day program, only 17 percent of the kids agreed or strongly agreed with the statement, “Science is boring.” Yet just 15 percent agreed or strongly agreed with the statement, “I want to become a scientist,” and only about 30 percent agreed or strongly agreed that scientists use their imagination and creativity throughout their investigations. After the day with the rovers, there was a statistically significant increase in the creativity rating, to about 35 percent. But   there was no change in the number of kids who wanted to be scientists.

My intention here isn’t to disparage what seems like a wonderful outreach program — if I lived in Australia I’d try to sign up for it myself. It would be crazy to expect a day-long field trip, however awesome, to immediately change a teenager’s career plans or philosophical outlook.

Still, the reason the program is great isn’t because it introduces kids to the exciting, multidisciplinary and provocative field of astrobiology. All fields of science, after all, are similarly   wondrous   and inspirational.

What we need to focus on instead is why the imagination of scientists doesn’t get through to most of the world’s young minds, even to those who are interested in science .

Are science journalists not describing it? Are science teachers ignoring it? Are scientists themselves too shy or modest or data-centric to spend much time talking about their creative process?

How can we fix this?

Interestingly, ratings from students in developing countries were much higher, around 3.

Images from   Ben Heine , cigcardpix , and   NASA Goddard

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Assessment of Mars Science and Mission Priorities (2003)

Chapter: 13. conclusions, 13 conclusions.

It is humankind’s nature to explore our surroundings if it can be done. Fifty years ago, exploring Mars was not one of the things anyone could do. Those who were curious had to be content with fuzzy images of the planet, quivering in the oculars of telescopes. But that is far from the case today. Forty years ago, spacecraft began to be sent to the planets, and since then, the art of space exploration has become increasingly refined and discoveries have multiplied. We now have the capability, in principle, of reaching and exploring any object in the solar system. At the top of the list of targets of exploration is Mars, the most Earth-like, most accessible, most hospitable, and most intriguing of the planets. Two years ago, in October 2000, NASA recognized this by setting the study of Mars apart in a structured Mars Exploration Program. The present document reports on COMPLEX’s study of the program.

COMPLEX has compared the elements of the Mars Exploration Program with the research objectives for Mars that have been stressed by advisory panels, including this one, for more than 23 years. The committee found that correspondence between the two is not perfect. Currently, NASA focuses on the search for life, and its prerequisite, water, as the main drivers for Mars research, and has favored missions and experiments that support these goals. The space agency is not now in a position to ask direct questions about life on Mars, and has not been since the Viking mission in the 1970s, but the missions supported are designed to find the areas most promising for water and life, and to investigate in situ their chemical and petrographic potential for extant or fossil life.

Since NASA operates within budget constraints, this emphasis on one particular scientific objective necessarily comes at the expense of others. COMPLEX considered the question of whether NASA’s priorities are too heavily skewed toward life-related investigations. The committee decided, however, that this is not the case. The emphasis on life is well justified; the life-related investigations that are planned range over so much of Mars science that they will result in broad and comprehensive gains in our knowledge; and the areas most neglected as a consequence of this emphasis (see Chapter 12 ) will, to some extent, be investigated by projected missions of our international partners.

COMPLEX endorses the program NASA has set up, though the committee has also pointed out several areas of high scientific priority that the program does not address. This report stresses the uniquely important role of sample return in a program of Mars research, and urges that sample-return missions be performed as early as possible. Discussions and recommendations related to sample return appear in Chapters 7 and 12 . A more general review of the conclusions of this report is contained in the Executive Summary.

FIGURE 13.1 The study of Mars has come very far. This map is a reminder of how the planet was perceived in 1967. SOURCE: Mariner 69 Mars Chart, NASA MEC-2.

Our understanding of the most Earth-like planet beyond our own has increased dramatically in 35 years of spacecraft research (see Figure 13.1). Most of us will live to see an even greater increment of knowledge result from execution of the Mars Exploration Program that this report describes.

Within the Office of Space Science of the National Aeronautics and Space Administration (NASA) special importance is attached to exploration of the planet Mars, because it is the most like Earth of the planets in the solar system and the place where the first detection of extraterrestrial life seems most likely to be made. The failures in 1999 of two NASA missions—Mars Climate Orbiter and Mars Polar Lander—caused the space agency's program of Mars exploration to be systematically rethought, both technologically and scientifically. A new Mars Exploration Program plan (summarized in Appendix A) was announced in October 2000. The Committee on Planetary and Lunar Exploration (COMPLEX), a standing committee of the Space Studies Board of the National Research Council, was asked to examine the scientific content of this new program. This goals of this report are the following:

-Review the state of knowledge of the planet Mars, with special emphasis on findings of the most recent Mars missions and related research activities;

-Review the most important Mars research opportunities in the immediate future;

-Review scientific priorities for the exploration of Mars identified by COMPLEX (and other scientific advisory groups) and their motivation, and consider the degree to which recent discoveries suggest a reordering of priorities; and

-Assess the congruence between NASA's evolving Mars Exploration Program plan and these recommended priorities, and suggest any adjustments that might be warranted.

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Life on Mars: A Definite Possibility

Was Mars once a living world? Does life continue, even today, in a holding pattern, waiting until the next global warming event comes along? Many people would like to believe so. Scientists are no exception. But so far no evidence has been found that convinces even a sizable minority of the scientific community that the red planet was ever home to life. What the evidence does indicate, though, is that Mars was once a habitable world . Life, as we know it, could have taken hold there.

The discoveries made by NASA ’s Opportunity rover at Eagle Crater earlier this year (and being extended now at Endurance Crater) leave no doubt that the area was once ‘drenched’ in water . It might have been shallow water. It might not have stuck around for long. And billions of years might have passed since it dried up. But liquid water was there, at the martian surface, and that means that living organisms might have been there, too.

So suppose that Eagle Crater – or rather, whatever land formation existed in its location when water was still around – was once alive. What type of organism might have been happy living there?

Probably something like bacteria. Even if life did gain a foothold on Mars, it’s unlikely that it ever evolved beyond the martian equivalent of terrestrial single-celled bacteria. No dinosaurs; no redwoods; no mosquitoes – not even sponges, or tiny worms. But that’s not much of a limitation, really. It took life on Earth billions of years to evolve beyond single-celled organisms. And bacteria are a hardy lot. They are amazingly diverse, various species occupying extreme niches of temperature from sub-freezing to above-boiling; floating about in sulfuric acid; getting along fine with or without oxygen. In fact, there are few habitats on Earth where one or another species of bacterium can’t survive.

What kind of microbe, then, would have been well adapted to the conditions that existed when Eagle Crater was soggy? Benton Clark III , a Mars Exploration Rover ( MER ) science team member, says his “general favorite” candidates are the sulfate-reducing bacteria of the genus Desulfovibrio . Microbiologists have identified more than 40 distinct species of this bacterium.

Eating Rocks

We tend to think of photosynthesis as the engine of life on Earth. After all, we see green plants nearly everywhere we look and virtually the entire animal kingdom is dependent on photosynthetic organisms as a source of food. Not only plants, but many microbes as well, are capable of carrying out photosynthesis. They’re photoautotrophs: they make their own food by capturing energy directly from sunlight.

But Desulfovibrio is not a photoautotroph; it’s a chemoautotroph. Chemoautotrophs also make their own food, but they don’t use photosynthesis to do it. In fact, photosynthesis came relatively late in the game of life on Earth. Early life had to get its energy from chemical interactions between rocks and dirt, water, and gases in the atmosphere. If life ever emerged on Mars, it might never have evolved beyond this primitive stage.

Desulfovibrio makes its home in a variety of habitats. Many species live in soggy soils, such as marshes and swamps. One species was discovered all snug and cozy in the intestines of a termite. All of these habitats have two things in common: there’s no oxygen present; and there’s plenty of sulfate available.

Sulfate reducers, like all chemoautotrophs, get their energy by inducing chemical reactions that transfer electrons between one molecule and another. In the case of Desulfovibrio, hydrogen donates electrons, which are accepted by sulfate compounds. Desulfovibrio, says Clark, uses “the energy that it gets by combining the hydrogen with the sulfate to make the organic compounds” it needs to grow and to reproduce.

The bedrock outcrop in Eagle Crater is chock full of sulfate salts. But finding a suitable electron donor for all that sulfate is a bit more troublesome. “My calculations indicate [that the amount of hydrogen available is] probably too low to utilize it under present conditions,” says Clark. “But if you had a little bit wetter Mars, then there [would] be more water in the atmosphere, and the hydrogen gas comes from the water” being broken down by sunlight.

So water was present; sulfate and hydrogen could have as an energy source. But to survive, life as we know it needs one more ingredient carbon. Many living things obtain their carbon by breaking down the decayed remains of other dead organisms. But some, including several species of Desulfovibrio, are capable of creating organic material from scratch, as it were, drawing this critical ingredient of life directly from carbon dioxide (CO 2 ) gas. There’s plenty of that available on Mars.

All this gives reason to hope that life that found a way to exist on Mars back in the day when water was present. No one knows how long ago that was. Or whether such a time will come again. It may be that Mars dried up billions of years ago and has remained dry ever since. If that is the case, life is unlikely to have found a way to survive until the present.

Tilting toward Life

But Mars goes through cycles of obliquity, or changes in its orbital tilt. Currently, Mars is wobbling back and forth between 15 and 35 degrees’ obliquity, on a timescale of about 100,000 years. But every million years or so, it leans over as much as 60 degrees. Along with these changes in obliquity come changes in climate and atmosphere. Some scientists speculate that during the extremes of these obliquity cycles, Mars may develop an atmosphere as thick as Earth’s, and could warm up considerably. Enough for dormant life to reawaken.

“Because the climate can change on long terms,” says Clark, ice in some regions on Mars periodically could “become liquid enough that you would be able to actually come to life and do some things – grow, multiply, and so forth – and then go back to sleep again” when the thaw cycle ended. There are organisms on Earth that, when conditions become unfavorable, can form “spores which are so resistant that they can last for a very long time. Some people think millions of years, but that’s a little controversial.”

Desulfovibrio is not such an organism. It doesn’t form spores. But its bacterial cousin, Desulfotomaculum, does. “Usually the spores form because there’s something missing, like, for example, if hydrogen’s not available, or if there’s too much [oxygen], or if there’s not sulfate. The bacteria senses that the food source is going away, and it says, ‘I’ve got to hibernate,’ and will form the spores. The spores will stay dormant for extremely long periods of time. But they still have enough machinery operative that they can actually sense that nutrients are available. And then they’ll reconvert again in just a matter of hours, if necessary, to a living, breathing bacterium, so to speak. It’s pretty amazing,” says Clark.

That is not to say that future Mars landers should arrive with life-detection equipment tuned to zero in on species of Desulfovibrio or Desulfotomaculum. There is no reason to believe that life on Mars, if it ever emerged, evolved along the same lines as life on Earth, let alone that identical species appeared on the two planets. Still, the capabilities of various organisms on Earth indicate that life on Mars – including dormant organisms that could spring to life again in another few hundred thousand years – is certainly possible.

Clark says that he doesn’t “know that there’s any organism on Earth that could really operate on Mars, but over a long period of time, as the martian environment kept changing, what you would expect is that whatever life had started out there would keep adapting to the environment as it changed.”

Detecting such organisms is another matter. Don’t look for it to happen any time soon. Spirit and Opportunity were not designed to search for signs of life, but rather to search for signs of habitability. They could be rolling over fields littered with microscopic organisms in deep sleep and they’d never know it. Even future rovers will have a tough time identifying the martian equivalent of dormant bacterial spores.

“The spores themselves are so inert,” Clark says, “it’s a question, if you find a spore, and you’re trying to detect life, how do you know it’s a spore, [and not] just a little particle of sand? And the answer is: You don’t. Unless you can find a way to make the spore do what’s called germinating, going back to the normal bacterial form.” That, however, is a challenge for another day.

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Origin of life on mars: suitability and opportunities.

1. Introduction

2. materials and methods, 2.1. organic molecules and elements, 2.2. energy sources, 2.3. planetary settings, 3.1. elements and molecules on mars, 3.1.1. organics and chnops elements, 3.1.2. transition elements, 3.1.3. other key elements, 3.1.4. elements availability, 3.2. energy sources on mars, 3.3. settings on mars, 3.3.1. early mars as compared to early earth, 3.3.2. subaerial terrain proto-macrobionts, 3.3.3. suboceanic hydrothermal proto-macrobionts, 4. discussion, 4.1. when would be an ool on mars: past, present, future, 4.2. where an ool would have been on mars, 4.3. likelihood for origin of life, 4.3.1. expected value for the ool, 4.3.2. lithopanspermia, 4.4. future research, author contributions, institutional review board statement, informed consent statement, acknowledgments, conflicts of interest, abbreviations.

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Clark, B.C.; Kolb, V.M.; Steele, A.; House, C.H.; Lanza, N.L.; Gasda, P.J.; VanBommel, S.J.; Newsom, H.E.; Martínez-Frías, J. Origin of Life on Mars: Suitability and Opportunities. Life 2021 , 11 , 539. https://doi.org/10.3390/life11060539

Clark BC, Kolb VM, Steele A, House CH, Lanza NL, Gasda PJ, VanBommel SJ, Newsom HE, Martínez-Frías J. Origin of Life on Mars: Suitability and Opportunities. Life . 2021; 11(6):539. https://doi.org/10.3390/life11060539

Clark, Benton C., Vera M. Kolb, Andrew Steele, Christopher H. House, Nina L. Lanza, Patrick J. Gasda, Scott J. VanBommel, Horton E. Newsom, and Jesús Martínez-Frías. 2021. "Origin of Life on Mars: Suitability and Opportunities" Life 11, no. 6: 539. https://doi.org/10.3390/life11060539

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Signs of Life on Mars? NASA’s Perseverance Rover Begins the Hunt

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The robotic arm on NASA’s Perseverance rover reached out to examine rocks in an area on Mars nicknamed the “Cratered Floor Fractured Rough” area in this image captured on July 10, 2021 (the 138th sol, or Martian day, of its mission).

After testing a bristling array of instruments on its robotic arm, NASA’s latest Mars rover gets down to business: probing rocks and dust for evidence of past life.

NASA’s Mars 2020 Perseverance rover has begun its search for signs of ancient life on the Red Planet. Flexing its 7-foot (2-meter) mechanical arm, the rover is testing the sensitive detectors it carries, capturing their first science readings. Along with analyzing rocks using X-rays and ultraviolet light, the six-wheeled scientist will zoom in for closeups of tiny segments of rock surfaces that might show evidence of past microbial activity.

NASA’s Perseverance Mars rover took this close-up of a rock target nicknamed “Foux” using its WATSON camera on the end of the rover’s robotic arm. The image was taken July 11, 2021, the 139th Martian day, or sol, of the mission.

Called PIXL , or Planetary Instrument for X-ray Lithochemistry, the rover’s X-ray instrument delivered unexpectedly strong science results while it was still being tested, said Abigail Allwood, PIXL’s principal investigator at NASA’s Jet Propulsion Laboratory in Southern California. Located at the end of the arm, the lunchbox-size instrument fired its X-rays at a small calibration target – used to test instrument settings – aboard Perseverance and was able to determine the composition of Martian dust clinging to the target.

“We got our best-ever composition analysis of Martian dust before it even looked at rock,” Allwood said.

That’s just a small taste of what PIXL, combined with the arm’s other instruments, is expected to reveal as it zeroes in on promising geological features over the weeks and months ahead.

Scientists say Jezero Crater was a crater lake billions of years ago, making it a choice landing site for Perseverance. The crater has long since dried out, and the rover is now picking its way across its red, broken floor .

“If life was there in Jezero Crater, the evidence of that life could be there,” said Allwood, a key member of the Perseverance “arm science” team.

PIXL, one of seven instruments aboard NASA's Perseverance Mars rover, is equipped with light diodes circling its opening to take pictures of rock targets in the dark. Using artificial intelligence, PIXL relies on the images to determine how far away it is from a target to be scanned.

To get a detailed profile of rock textures, contours, and composition, PIXL’s maps of the chemicals throughout a rock can be combined with mineral maps produced by the SHERLOC instrument and its partner, WATSON. SHERLOC – short for Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals – uses an ultraviolet laser to identify some of the minerals in the rock, while WATSON takes closeup images that scientists can use to determine grain size, roundness, and texture, all of which can help determine how the rock was formed.

Early WATSON closeups have already yielded a trove of data from Martian rocks, the scientists said, such as a variety of colors, sizes of grains in the sediment, and even the presence of “cement” between the grains. Such details can provide important clues about formation history, water flow, and ancient, potentially habitable Martian environments. And combined with those from PIXL, they can provide a broader environmental and even historical snapshot of Jezero Crater.

“What is the crater floor made out of? What were the conditions like on the crater floor?” asks Luther Beegle of JPL, SHERLOC’s principal investigator. “That does tell us a lot about the early days of Mars, and potentially how Mars formed. If we have an idea of what the history of Mars is like, we’ll be able to understand the potential for finding evidence of life.”

This data shows chemicals detected within a single rock on Mars by PIXL, one of the instruments on the end of the robotic arm aboard NASA’s Perseverance Mars rover. PIXL allows scientists to study where specific chemicals can be found within an area as small as a postage stamp.

The Science Team

While the rover has significant autonomous capabilities, such as driving itself across the Martian landscape, hundreds of earthbound scientists are still involved in analyzing results and planning further investigations.

“There are almost 500 people on the science team,” Beegle said. “The number of participants in any given action by the rover is on the order of 100. It’s great to see these scientists come to agreement in analyzing the clues, prioritizing each step, and putting together the pieces of the Jezero science puzzle.”

That will be critical when the Mars 2020 Perseverance rover collects its first samples for eventual return to Earth. They’ll be sealed in superclean metallic tubes on the Martian surface so that a future mission could collect them and send back to the home planet for further analysis.

Despite decades of investigation on the question of potential life, the Red Planet has stubbornly kept its secrets.

“Mars 2020, in my view, is the best opportunity we will have in our lifetime to address that question,” said Kenneth Williford, the deputy project scientist for Perseverance.

The geological details are critical, Allwood said, to place any indication of possible life in context, and to check scientists’ ideas about how a second example of life’s origin could come about.

Combined with other instruments on the rover, the detectors on the arm, including SHERLOC and WATSON, could make humanity’s first discovery of life beyond Earth.

More About the Mission

A key objective for Perseverance’s mission on Mars is astrobiology , including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

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April 5, 2023

NASA’s Perseverance Rover May Already Have Evidence of Ancient Martian Life

A half-kilogram’s worth of samples gathered by NASA’s Perseverance rover for eventual return to Earth holds weighty implications for life on Mars

By Jonathan O'Callaghan

NASA’s Perseverance Mars rover took a selfie with several of the 10 sample tubes it deposited at a sample depot it is creating within an area of Jezero Crater nicknamed Three Forks.

NASA/JPL-Caltech/MSSS

If life ever existed on Mars, we may already have the answer at hand. In January NASA’s Perseverance rover deposited 10 tubes on the surface of Mars. Each contains a sample of Martian rock that was carefully selected for its potential to clarify chapters of the planet’s still-murky history. Those tubes “are capable of telling us whether Mars was habitable,” says Mitch Schulte, Perseverance’s program scientist at NASA Headquarters in Washington, D.C. “We see evidence of particular minerals that tell us there was water. Some of these minerals indicate there was organic material.”

But to know for sure, scientists need to bring these tubes back to Earth for closer study—an audacious endeavor known as Mars Sample Return (MSR), which is slated for the early 2030s via a follow-up robotic mission . These 10 tubes are only the opening course in a bigger awaiting feast, a backup cache in case Perseverance breaks down before it can fill and deliver the 33 additional tubes that it carries. These tubes will hold samples sourced from the area in and around Jezero Crater, the site of a four-billion-year-old river delta and the locale where the rover landed on February 18, 2021. Although many of the samples are yet to be gathered for a journey to Earth that remains years in the future, those already collected have whetted researchers’ appetite for their return home.

Scientists targeted Jezero for Perseverance because, on our planet, sprawling river systems like that found in the Martian crater build up enormous deposits of sediments. Washed in from a sizable swath of the surrounding landscape, these deposits contain various minerals that can be used to chart the Red Planet’s past geology. Also most anywhere water is found on Earth, life accompanies it. The same might hold true for Mars, meaning Jezero’s sediments could conceivably harbor biological remains. “We’re looking for signs of habitability—liquid water and the raw materials of life,” says Mark Sephton of Imperial College London, a member of the rover’s sampling team.

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A close-up of one of the Perseverance Mars rover’s 43 sample tubes, deposited for future retrieval on the surface of Mars. Credit: NASA/JPL-Caltech/MSSS

Perseverance collects most of its samples using a small drill, producing chalk-stick-sized specimens that each fit within cigarlike tubes measuring less than 15 centimeters long. Of the 43 sample tubes, 38 are slated for samples from the surface, with the remaining five being “witness tubes” to catch whiffs of Martian air and check for any contaminating gases that might vent from the rover. Collected in September 2021 , the rover’s first sample is thought to be igneous rock from an ancient lava flow. Studying this material should allow scientists to date the crater more precisely. Since then, the rover has filled nearly half of its remaining tubes as it journeys several kilometers further up the ancient river’s channels toward Jezero Crater’s rim.

As a contingency, 10 of the samples are duplicates, each paired with another sample taken from the same location. These are the tubes Perseverance dropped on the surface as backup for potential future retrieval. In December 2022, in one of the last decisions he’d make at the space agency before reentering the private sector, NASA’s then science chief Thomas Zurbuchen made the call to drop that cache at a location called Three Forks. The surface drop-off was completed at the end of January, around the same time Perseverance officially began the “extended” phase of its mission—and after the science team agreed that those 10 samples alone could answer the question of past habitability if needed. MSR’s optimal plan calls for the rover to carry its remaining tubes to a yet-to-be-built lander slated to touch down in Jezero’s vicinity around 2030. Once the lander has secured those samples, it will launch them on a rocket back to Earth .

“We want the ones on the rover to come back,” Zurbuchen says. “But even the ones on the surface check all the boxes.” That includes igneous rock to date the crater and sedimentary rock and clays that may contain biosignatures, perhaps even fossilized evidence of microbial life. “They’re already worth the $10-billion investment,” Zurbuchen says, citing the MSR program’s estimated total cost. Some of the most promising samples are from a location called Wildcat Ridge, a meter-wide rock that contains evidence of sulfates. “Those are the ones we’re most excited about in terms of potential biosignatures,” says Kathleen Benison of West Virginia University, who is part of Perseverance’s sampling team. “Sulfate minerals can grow from groundwater. On Earth, those kinds of waters tend to have a lot of microbial life,” which can be entombed and preserved in sulfate minerals.

Besides sulfates, life-seeking scientists are particularly eager to grab samples from mudstones—fine-grained sedimentary rocks that the Curiosity rover has seen in Gale Crater but that Perseverance has not yet spotted. “Microbe cells are tiny,” says Tanja Bosak of the Massachusetts Institute of Technology, who is also part of the sampling team. “The mineral grain size should be even finer to preserve the [fossil] shape instead of destroying it. If you roll a boulder over a person, you will smush that person into something unrecognizable. For a microbe, everything is a boulder—unless you’re talking about mudstones.” The team members are also keen to sample carbonates, similar to things like chalk and limestone on Earth, which could preserve biosignatures as well. “If there had been microbial life in the lake, [the carbonates] could have trapped microbial matter in it,” says Sanjeev Gupta of Imperial College London, who is one of the “long-term planners” who plot out the rover’s path. On March 30, Perseverance collected its first carbonate sample, from a rock named “Berea” thought to have formed from material washed into Jezero by the ancient river.

Taken on March 30, 2023, this image shows the rocky outcrop the Perseverance science team calls “Berea” after the NASA Mars rover extracted a carbonate rock core ( right ) and abraded a circular patch ( left ). Credit: NASA/JPL-Caltech

While Perseverance has been hard at work collecting samples on Mars, the return phase of the mission remains in flux. Originally, NASA had planned for a European-built “fetch” rover to land on Mars around 2030, collect the samples from Perseverance and return them to a capsule on the lander for launch. Once in orbit, the sample capsule would rendezvous with a European orbiter, which would ferry the samples back to Earth for a landing in 2033. These plans were complicated, however, by Russia’s invasion of Ukraine in 2022. In response to Russia’s aggression, European Space Agency (ESA) officials chose to step back from a partnership with the nation on another long-simmering Mars mission, the Rosalind Franklin ExoMars rover. Russia had been due to provide the rover’s nuclear power source, as well as the launch vehicle and landing platform. NASA has now agreed to supply such missing pieces and has sought funding to do so in its budgetary request to Congress last month. But this unanticipated assistance comes at the cost of the fetch rover. “We couldn’t do both,” Zurbuchen says. “We could not individually land the fetch rover and do ExoMars.”

The ExoMars mission, most everyone agrees, is eminently worth saving. The Rosalind Franklin rover will carry a drill that can augur two meters beneath the Martian surface, accessing a subterranean habitat for past and present life that is considerably less hostile than the surface. “Nobody has ever done that on Mars,” Zurbuchen says. “Our science community thinks it’s really important.”

Jorge Vago, ESA’s ExoMars project scientist in the Netherlands, was glad that NASA stepped in. To hit a target launch date of 2028, set forth by European member states in order to save the mission, “we need the American contributions,” Vago says. “It’s an amazing mission. If we find super interesting stuff that’s suggestive of a possible biological origin, I would expect we may want to have another sample return mission and bring back samples from the subsurface.”

NASA’s current MSR plan faces its own challenges. In a mid-March town hall hosted by NASA’s Science Mission Directorate, Jeff Gramling, MSR program director at NASA Headquarters, said that some aspects of the mission may need to be “descoped.” This would be a preventative measure to keep budgets under control. NASA’s annual request of nearly $1 billion for MSR is expected to grow in the next few years, raising fears that unchecked increases could force the space agency to siphon funds from unrelated missions. Descoping options include removing one of two “Marscopters” planned for MSR, which had been included to build on the wildly successful Ingenuity rotorcraft that is now approaching 50 flights on Mars . Among other tasks, MSR’s helicopters were added as a backup option for collecting the 10-tube sample cache at Three Forks. “The mission remains complex,” Gramling said during the town hall. “We’re working to our earliest possible launch date.”

Despite the overwhelmingly intricate logistics of seeking life on Mars, the scientific riches on offer have lost none of their luster. Perseverance’s returned samples will cumulatively be only about half a kilogram, but the weight of their implications is immeasurable. Will they reveal that a second genesis of life in the universe has unfolded on the surface of Mars? For that matter, will Rosalind Franklin, once it arrives, validate the long-held suspicion that Mars’s subsurface was—or still is—habitable, too? In our winding quest to determine if we are alone in the universe, the answer may be practically within our grasp, merely waiting for us to reach out to claim it. “We won’t know until we get the samples back,” Bosak says.

Has Nasa found evidence of ancient life on Mars? An expert examines the latest discovery

Reader in Astrobiology, The University of Edinburgh

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Sean McMahon has received funding from Nasa.

The University of Edinburgh provides funding as a member of The Conversation UK.

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Nasa has announced the first detection of possible biosignatures in a rock on the surface of Mars. The rock contains the first martian organic matter to be decisively detected by the Perseverance rover , as well as curious discoloured spots that could indicate the past activity of microorganisms.

Ken Farley, project scientist on the mission, has called this “the most puzzling, complex, and potentially important rock yet investigated by Perseverance”.

Perseverance is part of Mars 2020, the first mission since Viking that is explicitly designed to seek life on Mars (officially, to “search for potential evidence of past life using observations regarding habitability and preservation as a guide”). Arguably, that objective has now been achieved: potential evidence for past life has been found. But much more work is needed to test this interpretation of the data. Here’s what we do know.

Since landing in Jezero crater a few years ago, Perseverance has traversed a series of rocks formed nearly four billion years before present. Mars back then was far more habitable than the cold, dry, toxic red planet of today.

There were thousands of rivers and lakes, a thick atmosphere, and comfortable temperatures and chemical conditions for life. Many of the rocks in Jezero are sedimentary: mud, silt and sand dumped by a river flowing into a lake.

The new discovery concerns one of these rocks. Informally named “Cheyava Falls” (a waterfall in Arizona), it is a small reddish block of what looks like a mudstone, enriched with organic molecules. The rock is also laced with parallel white veins. Between the veins are millimetre-scale whitish spots with dark rims. For an astrobiologist, all these features are intriguing. Let’s take them one-by-one.

First, “organic molecules” , are made of carbon and hydrogen (commonly with sulphur, oxygen or nitrogen as well). Examples include the proteins, fats, sugars, and nucleic acids from which all life as we know it is constructed.

Organic matter is common in rocks on Earth, most of it derived from the remains of ancient organisms. But the term “organic” is slightly misleading: such molecules can also be produced by non-biological reactions (in fact, we know this was happening four billion years ago on Mars).

Simple non-biological organic molecules are common in the universe, and Nasa’s Curiosity rover already found them in mudstones in Gale Crater. They were also reportedly detected by Perseverance in Jezero crater last year.

Nevertheless, Ken Farley considers the new observation the first truly “compelling detection” of organics made by Perseverance. Nasa has not told us which types of organic molecules are actually present in Cheyava Falls, so it is hard to evaluate their origins. They could turn out to be biological, but a full analysis using laboratories on Earth would be needed to settle this question.

Next, the veins. These are composed of calcium sulphate, which precipitated like limescale when liquid water ran along fractures in the subsurface. Veins like these are common in Martian sedimentary rocks (Curiosity saw plenty of them), and of course they are not “biosignatures” even though they normally represent habitable conditions.

My own work has shown that microorganisms inhabiting subsurface fractures can produce chemical fossils that get trapped in calcium sulphate veins. Strangely, however, the veins in Cheyava Falls also contain olivine, an igneous mineral. This might suggest that the water was injected at temperatures too high for life. We need more data to know one way or the other.

Finally, what about those whitish, discoloured spots? These look like the “reduction spots”, also called “leopard spots”, commonly seen in red sedimentary rocks on Earth. Such rocks are rusty-red because they contain an oxidised form of iron. When chemical reactions modify the iron to a less oxidised state, it becomes soluble. Water carries the pigment away leaving a bleached spot behind.

On Earth, these reactions are often driven by subsurface-dwelling bacteria. They use the oxidised iron as a source of energy, just as you and I use oxygen in the air. On Mars, bacteria-like organisms could have used the organic matter in the rock to complete the reaction (just as we use glucose from the food we eat).

Reduction spots haven’t been seen before on Mars, although bleached linear “halos” observed by Curiosity in Gale crater are somewhat similar. As one of the few astrobiologists to have studied reduction spots on Earth – and found evidence for biological processes within them – I am personally delighted. But as ever, caution is needed.

Potential non-biological causes need to be explored and ruled out. Iron-dissolving reactions can and do happen in sedimentary rocks without life. The dark margins of the Cheyava Falls spots are enriched in both iron and phosphate, an association previously suggested to occur around some calcium sulphate veins on Mars. This observation is consistent with life, but also with chemical reactions driven by acidic fluids.

The new findings will nevertheless embolden those calling on Nasa and the European Space Agency to proceed with the troubled multi-billion-dollar sample retrieval programme , which Perseverance was supposed to begin. The rover has now cored out a piece of the Cheyava Falls rock. If current plans are realised – a big if – then future spacecraft will collect this piece (and others) and bring it to Earth.

It will then be analysed in state-of-the-art laboratories far more capable than the instruments aboard Perseverance. Until that happens, we cannot be sure whether Perseverance has really found fossils of ancient life on Mars. The evidence so far is not definitive, but it is certainly tantalising.

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Essay on Life on Mars for Students and Children

500 words essay on life on mars.

Mars is the fourth planet from the sun in our solar system. Also, it is the second smallest planet in our solar system. The possibility of life on mars has aroused the interest of scientists for many years. A major reason for this interest is due to the similarity and proximity of the planet to Earth. Mars certainly gives some indications of the possibility of life.

Possibilities of Life on Mars

In the past, Mars used to look quite similar to Earth. Billions of years ago, there were certainly similarities between Mars and Earth. Furthermore, scientists believe that Mars once had a huge ocean. This ocean, experts believe, covered more of the planet’s surface than Earth’s own oceans do so currently.

Moreover, Mars was much warmer in the past that it is currently. Most noteworthy, warm temperature and water are two major requirements for life to exist. So, there is a high probability that previously there was life on Mars.

Life on Earth can exist in the harshest of circumstances. Furthermore, life exists in the most extreme places on Earth. Moreover, life on Earth is available in the extremely hot and dry deserts. Also, life exists in the extremely cold Antarctica continent. Most noteworthy, this resilience of life gives plenty of hope about life on Mars.

There are some ingredients for life that already exist on Mars. Bio signatures refer to current and past life markers. Furthermore, scientists are scouring the surface for them. Moreover, there has been an emergence of a few promising leads. One notable example is the presence of methane in Mars’s atmosphere. Most noteworthy, scientists have no idea where the methane is coming from. Therefore, a possibility arises that methane presence is due to microbes existing deep below the planet’s surface.

One important point to note is that no scratching of Mars’s surface has taken place. Furthermore, a couple of inches of scratching has taken place until now. Scientists have undertaken analysis of small pinches of soil. There may also have been a failure to detect signs of life due to the use of faulty techniques. Most noteworthy, there may be “refugee life” deep below the planet’s surface.

Get the huge list of more than 500 Essay Topics and Ideas

Challenges to Life on Mars

First of all, almost all plants and animals cannot survive the conditions on the surface of Mars. This is due to the extremely harsh conditions on the surface of Mars.

Another major problem is the gravity of Mars. Most noteworthy, the gravity on Mars is 38% to that of Earth. Furthermore, low gravity can cause health problems like muscle loss and bone demineralization.

The climate of Mars poses another significant problem. The temperature at Mars is much colder than Earth. Most noteworthy, the mean surface temperatures of Mars range between −87 and −5 °C. Also, the coldest temperature on Earth has been −89.2 °C in Antarctica.

Mars suffers from a great scarcity of water. Most noteworthy, water discovered on Mars is less than that on Earth’s driest desert.

Other problems include the high penetration of harmful solar radiation due to the lack of ozone layer. Furthermore, global dust storms are common throughout Mars. Also, the soil of Mars is toxic due to the high concentration of chlorine.

To sum it up, life on Mars is a topic that has generated a lot of curiosity among scientists and experts. Furthermore, establishing life on Mars involves a lot of challenges. However, the hope and ambition for this purpose are well alive and present. Most noteworthy, humanity must make serious efforts for establishing life on Mars.

FAQs on Life on Mars

Q1 State any one possibility of life on Mars?

A1 One possibility of life on Mars is the resilience of life. Most noteworthy, life exists in the most extreme places on Earth.

Q2 State anyone challenge to life on Mars?

A2 One challenge to life on Mars is a great scarcity of water.

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Signs of life on mars nasa’s perseverance rover begins the hunt, jet propulsion laboratory, the science team, more about the mission.

After testing a bristling array of instruments on its robotic arm, NASA’s latest Mars rover gets down to business: probing rocks and dust for evidence of past life.

NASA’s Mars 2020 Perseverance rover has begun its search for signs of ancient life on the Red Planet. Flexing its 7-foot (2-meter) mechanical arm, the rover is testing the sensitive detectors it carries, capturing their first science readings. Along with analyzing rocks using X-rays and ultraviolet light, the six-wheeled scientist will zoom in for closeups of tiny segments of rock surfaces that might show evidence of past microbial activity.

Called PIXL , or Planetary Instrument for X-ray Lithochemistry, the rover’s X-ray instrument delivered unexpectedly strong science results while it was still being tested, said Abigail Allwood, PIXL’s principal investigator at NASA’s Jet Propulsion Laboratory in Southern California. Located at the end of the arm, the lunchbox-size instrument fired its X-rays at a small calibration target – used to test instrument settings – aboard Perseverance and was able to determine the composition of Martian dust clinging to the target.

“We got our best-ever composition analysis of Martian dust before it even looked at rock,” Allwood said.

That’s just a small taste of what PIXL, combined with the arm’s other instruments, is expected to reveal as it zeroes in on promising geological features over the weeks and months ahead.

Scientists say Jezero Crater was a crater lake billions of years ago, making it a choice landing site for Perseverance. The crater has long since dried out, and the rover is now picking its way across its red, broken floor .

“If life was there in Jezero Crater, the evidence of that life could be there,” said Allwood, a key member of the Perseverance “arm science” team.

To get a detailed profile of rock textures, contours, and composition, PIXL’s maps of the chemicals throughout a rock can be combined with mineral maps produced by the SHERLOC instrument and its partner, WATSON. SHERLOC – short for Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals – uses an ultraviolet laser to identify some of the minerals in the rock, while WATSON takes closeup images that scientists can use to determine grain size, roundness, and texture, all of which can help determine how the rock was formed.

Early WATSON closeups have already yielded a trove of data from Martian rocks, the scientists said, such as a variety of colors, sizes of grains in the sediment, and even the presence of “cement” between the grains. Such details can provide important clues about formation history, water flow, and ancient, potentially habitable Martian environments. And combined with those from PIXL, they can provide a broader environmental and even historical snapshot of Jezero Crater.

“What is the crater floor made out of? What were the conditions like on the crater floor?” asks Luther Beegle of JPL, SHERLOC’s principal investigator. “That does tell us a lot about the early days of Mars, and potentially how Mars formed. If we have an idea of what the history of Mars is like, we’ll be able to understand the potential for finding evidence of life.”

While the rover has significant autonomous capabilities, such as driving itself across the Martian landscape, hundreds of earthbound scientists are still involved in analyzing results and planning further investigations.

“There are almost 500 people on the science team,” Beegle said. “The number of participants in any given action by the rover is on the order of 100. It’s great to see these scientists come to agreement in analyzing the clues, prioritizing each step, and putting together the pieces of the Jezero science puzzle.”

That will be critical when the Mars 2020 Perseverance rover collects its first samples for eventual return to Earth. They’ll be sealed in superclean metallic tubes on the Martian surface so that a future mission could collect them and send back to the home planet for further analysis.

Despite decades of investigation on the question of potential life, the Red Planet has stubbornly kept its secrets.

“Mars 2020, in my view, is the best opportunity we will have in our lifetime to address that question,” said Kenneth Williford, the deputy project scientist for Perseverance.

The geological details are critical, Allwood said, to place any indication of possible life in context, and to check scientists’ ideas about how a second example of life’s origin could come about.

Combined with other instruments on the rover, the detectors on the arm, including SHERLOC and WATSON, could make humanity’s first discovery of life beyond Earth.

A key objective for Perseverance’s mission on Mars is astrobiology , including the search for signs of ancient microbial life. The rover will characterize the planet’s geology and past climate, pave the way for human exploration of the Red Planet, and be the first mission to collect and cache Martian rock and regolith (broken rock and dust).

Subsequent NASA missions, in cooperation with ESA (European Space Agency), would send spacecraft to Mars to collect these sealed samples from the surface and return them to Earth for in-depth analysis.

The Mars 2020 Perseverance mission is part of NASA’s Moon to Mars exploration approach, which includes Artemis missions to the Moon that will help prepare for human exploration of the Red Planet.

JPL, which is managed for NASA by Caltech in Pasadena, California, built and manages operations of the Perseverance rover.

For more about Perseverance:

mars.nasa.gov/mars2020/

nasa.gov/perseverance

DC Agle  Jet Propulsion Laboratory, Pasadena, Calif. 818-393-9011 [email protected]

Karen Fox / Alana Johnson NASA Headquarters, Washington 301-286-6284 / 202-358-1501 [email protected] / [email protected]