An extremophile is an organism that is able to live in extreme environments, i.e. environments with conditions approaching or expanding the limits of what known life can adapt to, such as extreme temperature, radiation, salinity, or pH level.
Panspermia is the hypothesis that life exists throughout the Universe, distributed by space dust, meteoroids, asteroids, comets, and planetoids, as well as by spacecraft carrying unintended contamination by microorganisms. Panspermia is a fringe theory with little support amongst mainstream scientists. Critics argue that it does not answer the question of the origin of life but merely places it on another celestial body. It is also criticized because it cannot be tested experimentally.
Surveyor 3 was the third lander of the American uncrewed Surveyor program sent to explore the surface of the Moon in 1967. It was the first mission to carry a surface-soil sampling-scoop.
The planet Mars has been explored remotely by spacecraft. Probes sent from Earth, beginning in the late 20th century, have yielded a large increase in knowledge about the Martian system, focused primarily on understanding its geology and habitability potential. Engineering interplanetary journeys is complicated and the exploration of Mars has experienced a high failure rate, especially the early attempts. Roughly sixty percent of all spacecraft destined for Mars failed before completing their missions and some failed before their observations could begin. Some missions have been met with unexpected success, such as the twin Mars Exploration Rovers, Spirit and Opportunity, which operated for years beyond their specification.
Planetary protection is a guiding principle in the design of an interplanetary mission, aiming to prevent biological contamination of both the target celestial body and the Earth in the case of sample-return missions. Planetary protection reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.
Bacillus safensis is a Gram-positive, spore-forming, and rod bacterium, originally isolated from a spacecraft in Florida and California. B. safensis could have possibly been transported to the planet Mars on spacecraft Opportunity and Spirit in 2004. There are several known strains of this bacterium, all of which belong to the Bacillota phylum of Bacteria. This bacterium also belongs to the large, pervasive genus Bacillus. B. safensis is an aerobic chemoheterotroph and is highly resistant to salt and UV radiation. B. safensis affects plant growth, since it is a powerful plant hormone producer, and it also acts as a plant growth-promoting rhizobacteria, enhancing plant growth after root colonization. Strain B. safensis JPL-MERTA-8-2 is the only bacterial strain shown to grow noticeably faster in micro-gravity environments than on the Earth surface.
As part of the Apollo 12 mission, the camera from the Surveyor 3 probe was brought back from the Moon to Earth. On analyzing the camera it was found that the common bacterium Streptococcus mitis was alive on the camera. This was attributed by NASA to the camera not being sterilized on Earth prior to its launch two and a half years previously. However, later study showed that the scientists analysing the camera on return to Earth used procedures that were inadequate to prevent recontamination after return to Earth, for instance with their arms exposed, not covering their entire bodies as modern scientists would do. There may also have been possibilities for contamination during the return mission as the camera was returned in a porous bag rather than the airtight containers used for lunar sample return. As a result, the source of the contamination remains controversial.
The idea of sending humans to Mars has been the subject of aerospace engineering and scientific studies since the late 1940s as part of the broader exploration of Mars. Long-term proposals have included sending settlers and terraforming the planet. Proposals for human missions to Mars have come from agencies such as NASA, CNSA, the European Space Agency, Boeing, and SpaceX. As of 2023, only robotic landers and rovers have been on Mars. The farthest humans have been beyond Earth is the Moon, under the Apollo program.
Bacillus odysseyi is a Gram-positive, aerobic, rod-shaped, round-spore- and endospore-forming eubacterium of the genus Bacillus. This novel species was discovered by scientist Myron T. La Duc of NASA’s Biotechnology and Planetary Protection Group, a unit whose purpose is to clean and sterilize spacecraft so as not to have microorganisms contaminate other celestial bodies or foreign microorganisms contaminate Earth, on the surface of the Mars Odyssey in a clean room at the Jet Propulsion Laboratory in La Cañada Flintridge before the spacecraft was launched to space. La Duc named the bacterium Bacillus odysseyi sp. nov. after the Odyssey mission. It had apparently evolved to live in the sparse environment of a clean room, and its secondary spore coat makes it especially resistant to radiation.
Astronautical hygiene evaluates, and mitigates, hazards and health risks to those working in low-gravity environments. The discipline of astronautical hygiene includes such topics as the use and maintenance of life support systems, the risks of the extravehicular activity, the risks of exposure to chemicals or radiation, the characterization of hazards, human factor issues, and the development of risk management strategies. Astronautical hygiene works side by side with space medicine to ensure that astronauts are healthy and safe when working in space.
Interplanetary contamination refers to biological contamination of a planetary body by a space probe or spacecraft, either deliberate or unintentional.
The Mars Science Laboratory and its rover, Curiosity, were launched from Earth on November 26, 2011. As of November 13, 2023, Curiosity has been on the planet Mars for 4007 sols since landing on August 6, 2012. (See Current status.)
Tersicoccus is a Gram-positive genus of bacteria from the family Micrococcaceae.
Exposing Microorganisms in the Stratosphere (E-MIST) is a NASA study to determine if a specific microorganism could survive conditions like those on the planet Mars. The study transported Bacillus pumilus bacteria and their spores by helium-filled balloon to the stratosphere of Earth and monitored the ability of the microorganisms to survive in extreme Martian-like conditions such as low pressure, dryness, cold, and ionizing radiation.
Microbiomes of the built environment is a field of inquiry into the communities of microorganisms that live in human constructed environments like houses, cars and water pipes. It is also sometimes referred to as microbiology of the built environment.
Naumannella halotolerans is a Gram-positive and aerobic bacterium from the genus Naumannella which has been isolated from a pharmaceutical clean room and milk products in Sachsen-Anhalt, Germany.
Barrientosiimonas marina is a Gram-positive, non-spore-forming, aerobic and non-motile bacterium from the genus Barrientosiimonas which has been isolated from seawater from the Mara Island in Korea.
Moogega Cooper is an American astronomer, and the Lead of Planetary Protection for the Mars 2020 Mission and is involved with the InSight Mission. Dr. Cooper also takes part in programs and speaking engagements to encourage young women or and others from underrepresented communities to pursue careers in science and technology.
Astrovirology is an emerging subdiscipline of astrobiology which aims to understand what role viruses played in the origin and evolution of life on Earth as well as the potential for viruses beyond Earth.
Vagococcus lutrae is a Gram-positive and coccus-shaped bacterium from the genus Vagococcus which has been isolated from a otter. Vagococcus lutrae can cause infection in humans in rare cases.
