The growth of plants in outer space has elicited much scientific interest. [1] In the late 20th and early 21st century, plants were often taken into space in low Earth orbit to be grown in a weightless but pressurized controlled environment, sometimes called space gardens. [1] In the context of human spaceflight, they can be consumed as food and provide a refreshing atmosphere. [2] Plants can metabolize carbon dioxide in the air to produce valuable oxygen, and can help control cabin humidity. [3] Growing plants in space may provide a psychological benefit to human spaceflight crews. [3] Usually the plants were part of studies or technical development to further develop space gardens or conduct science experiments. [1] To date plants taken into space have had mostly scientific interest, with only limited contributions to the functionality of the spacecraft, however the Apollo Moon tree project was more or less forestry inspired mission and the trees are part of a country's bicentennial celebration.
The first challenge in growing plants in space is how to get plants to grow without gravity. [4] This runs into difficulties regarding the effects of gravity on root development, soil integration, and watering without gravity, providing appropriate types of lighting, and other challenges. In particular, the nutrient supply to root as well as the nutrient biogeochemical cycles, and the microbiological interactions in soil-based substrates are particularly complex, but have been shown to make possible space farming in hypo- and micro-gravity. [5] [6]
NASA plans to grow plants in space to help feed astronauts and to provide psychological benefits for long-term space flight. [7] In 2017, aboard ISS in one plant growth device, the 5th crop of Chinese cabbage (Brassica rapa) from it included an allotment for crew consumption, while the rest was saved for study. [8] An early discussion of plants in space, were the trees on the brick moon space station, in the 1869 short story "The Brick Moon". [9]
In the 2010s there was an increased desire for long-term space missions, which led to desire for space-based plant production as food for astronauts. [10] An example of this is vegetable production on the International Space Station in Earth orbit. [10] By the year 2010, 20 plant growth experiments had been conducted aboard the International Space Station. [1]
Several experiments have been focused on how plant growth and distribution compares in micro-gravity, space conditions versus Earth conditions. This enables scientists to explore whether certain plant growth patterns are innate or environmentally driven. For instance, Allan H. Brown tested seedling movements aboard the Space Shuttle Columbia in 1983. Sunflower seedling movements were recorded while in orbit. They observed that the seedlings still experienced rotational growth and circumnutation despite lack of gravity, showing these behaviors are instinctual. [11]
Other experiments have found that plants have the ability to exhibit gravitropism, even in low-gravity conditions. For instance, the ESA's European Modular Cultivation System [12] enables experimentation with plant growth; acting as a miniature greenhouse, scientists aboard the International Space Station can investigate how plants react in variable-gravity conditions. The Gravi-1 experiment (2008) utilized the EMCS to study lentil seedling growth and amyloplast movement on the calcium-dependent pathways. [13] The results of this experiment found that the plants were able to sense the direction of gravity even at very low levels. [14] A later experiment with the EMCS placed 768 lentil seedlings in a centrifuge to stimulate various gravitational changes; this experiment, Gravi-2 (2014), displayed that plants change calcium signalling towards root growth while being grown in several gravity levels. [15]
Many experiments have a more generalized approach in observing overall plant growth patterns as opposed to one specific growth behavior. One such experiment from the Canadian Space Agency, for example, found that white spruce seedlings grew differently in the anti-gravity space environment compared with Earth-bound seedlings; [16] the space seedlings exhibited enhanced growth from the shoots and needles, and also had randomized amyloplast distribution compared with the Earth-bound control group. [17]
Food production is key to making Space exploration feasible. Currently, the cost of sending food to the International Space Station (ISS) is estimated as USD$20 000–40 000/kg, with each crew member receiving ~1.8 kg of food (plus packaging) per day . Re-stocking from Earth, a lunar orbiting Space station or Mars habitation with food will be significantly more costly. The first trips to Mars are expected to be a three-year round trip, and it has been estimated that a four-person crew would need 10–11 000 kgs of food. [18]
The first organisms in space were "specially developed strains of seeds" launched to 134 km (83 mi) on 9 July 1946 on a U.S. launched V-2 rocket. These samples were not recovered. The first seeds launched into space and successfully recovered were maize seeds launched on 30 July 1946. Soon followed rye and cotton. These early suborbital biological experiments were handled by Harvard University and the Naval Research Laboratory and were concerned with radiation exposure on living tissue. [19] On September 22 1966, Kosmos 110 launched with two dogs and moisturized seeds. Several of those seeds germinated, the first to do so, resulting in lettuce, cabbage and some beans that had greater yield than their controls on Earth. [20] In 1971, 500 tree seeds (Loblolly pine, Sycamore, Sweetgum, Redwood, and Douglas fir) were flown around the Moon on Apollo 14. These Moon trees were planted and grown with controls back on Earth where no changes were detected.
In 1982, the crew of the Soviet Salyut 7 space station conducted an experiment, prepared by Lithuanian scientists (Alfonsas Merkys and others), and grew some Arabidopsis using Fiton-3 experimental micro-greenhouse apparatus, thus becoming the first plants to flower and produce seeds in space. [22] [23] A Skylab experiment studied the effects of gravity and light on rice plants. [24] [25] The SVET-2 Space Greenhouse successfully achieved seed to seed plant growth in 1997 aboard space station Mir . [3] Bion 5 carried Daucus carota and Bion 7 carried maize (aka corn).
Plant research continued on the International Space Station. Biomass Production System was used on the ISS Expedition 4. The Vegetable Production System (Veggie) system was later used aboard ISS. [26] Plants tested in Veggie before going into space included lettuce, Swiss chard, radishes, Chinese cabbage and peas. [27] Red Romaine lettuce was grown in space on Expedition 40 which were harvested when mature, frozen and tested back on Earth. Expedition 44 members became the first American astronauts to eat plants grown in space on 10 August 2015, when their crop of Red Romaine was harvested. [28] Since 2003 Russian cosmonauts have been eating half of their crop while the other half goes towards further research. [29] In 2012, a sunflower bloomed aboard the ISS under the care of NASA astronaut Donald Pettit. [30] In January 2016, US astronauts announced that a zinnia had blossomed aboard the ISS. [31]
In 2017 the Advanced Plant Habitat was designed for ISS, which was a nearly self-sustaining plant growth system for that space station in low Earth orbit. [32] The system is installed in parallel with another plant grown system aboard the station, VEGGIE, and a major difference with that system is that APH is designed to need less upkeep by humans. [32] APH is supported by the Plant Habitat Avionics Real-Time Manager. [32] Some plants that were to be tested in APH include Dwarf Wheat and Arabidopsis. [32] In December 2017 hundreds of seeds were delivered to ISS for growth in the VEGGIE system. [33] APH is an important advancement in the understanding of plant growth in space and therefore the future of space exploration in general. [34]
In 2018 the Veggie-3 experiment at the ISS, was tested with plant pillows and root mats. [35] One of the goals is to grow food for crew consumption. [35] Crops tested at this time include cabbage, lettuce, and mizuna. [35] In 2018, the PONDS system for nutrient deliver in microgravity was tested. [36]
In December 2018, the German Aerospace Center launched the EuCROPIS satellite into low Earth orbit. This mission carried two greenhouses intended to grow tomatoes under simulated gravity of first the Moon and then Mars (6 months each) using by-products of human presence in space as source of nutrients. When scientists activated the experiment, they found that the greenhouses were functional, but the irrigation system was not; therefore the dormant seeds could not be used. [37]
The Seedling Growth series of experiments to study the mechanisms of tropisms and the cell/cycle were performed on the ISS between 2013 and 2017. [38] [39] These experiments also involved using the model plant Arabidopsis thaliana, and were a collaboration between NASA (John Z. Kiss as PI) and ESA (F. Javier Medina as PI). [39] [40]
On 30 November 2020, astronauts aboard the ISS collected the first harvest of radishes grown on the station. A total of 20 plants was collected and prepared for transportation back to Earth. There are currently plans to repeat the experiment and grow a second batch. [41]
Chang'e 4 lunar lander in January 2019, carried a 3 kg (6.6 lb) sealed "biosphere" with many seeds and insect eggs to test whether plants and insects could hatch and grow together in synergy. [42] The experiment included seeds of potatoes, tomatoes, and Arabidopsis thaliana (a flowering plant), as well as silkworm eggs. On January 15, 2019, it was reported that cotton seeds had grown in the biosphere - this became the first plant grown on the Moon. [43] [44] Environmental systems were in place to keep the container hospitable and Earth-like, except for the low lunar gravity. [45] It was hoped that if the eggs hatched, the larvae would produce carbon dioxide, while the germinated plants would release oxygen through photosynthesis. It was hoped that together, the plants and silkworms can establish a simple synergy within the container. A miniature camera was to photograph any growth. The biological experiment was designed by 28 Chinese universities. [46] [47]
In 2023 it was reported that the original 100 day experiment was scaled back to 9 days; the insects did not hatch and the potatoes did not sprout. [48] The cotton survived for 2 days before succumbing to temperature changes. [49]
Lunar soil has also been proven[ verification needed ] to allow plants to grow on, tested in a laboratory at the University of Florida. [50] These experiments showed that while the plant Arabidopsis thaliana can germinate and grow in lunar soil, that there are challenges presented in the plants ability to thrive, as many were slow to develop. Plants that did germinate showed morphological and transcriptomic indications of stress. [51]
Plants grown in space include:
Some experiments involving plants include:
The Vegetable Production System (Veggie), began in May 2014 aboard the ISS. This included; [79]
Animals in space originally served to test the survivability of spaceflight, before human spaceflights were attempted. Later, many species were flown to investigate various biological processes and the effects microgravity and space flight might have on them. Bioastronautics is an area of bioengineering research that spans the study and support of life in space. To date, seven national space programs have flown non-human animals into space: the United States, Soviet Union, France, Argentina, China, Japan and Iran.
The Destiny module, also known as the U.S. Lab, is the primary operating facility for U.S. research payloads aboard the International Space Station (ISS). It was berthed to the Unity module and activated over a period of five days in February, 2001. Destiny is NASA's first permanent operating orbital research station since Skylab was vacated in February 1974.
Aeroponics is the process of cultivating plants in an air or mist environment, eliminating the need for soil or an aggregate medium. The term "aeroponic" originates from the ancient Greek: aer (air) and ponos. It falls under the category of hydroponics, as water is employed in aeroponics to deliver nutrients to the plants.
Moon trees are trees grown from seeds taken into orbit around the Moon, initially by Apollo 14 in 1971, and later by Artemis 1 in 2022. The idea was first proposed by Edward P. Cliff, then the Chief of the United States Forest Service, who convinced Stuart Roosa, the Command Module Pilot on the Apollo 14 mission, to bring a small canister containing about 500 seeds aboard the module in 1971. Seeds for the experiment were chosen from five species of tree: loblolly pine, sycamore, sweetgum, redwood, and Douglas fir. In 2022, NASA announced it would be reviving the Moon tree program by carrying 1,000 seeds aboard Artemis 1.
Space manufacturing or In-space manufacturing is the fabrication, assembly or integration of tangible goods beyond Earth's atmosphere, involving the transformation of raw or recycled materials into components, products, or infrastructure in space, where the manufacturing process is executed either by humans or automated systems by taking advantage of the unique characteristics of space. Synonyms of Space/In-space manufacturing are In-orbit manufacturing, Off-Earth manufacturing, Space-based manufacturing, Orbital manufacturing, In-situ manufacturing, In-space fabrication, In-space production, etc. In-space manufacturing is a part of the broader activity of in-space servicing, assembly and manufacturing (ISAM) and is related to in situ resource utilization (ISRU).
Space food is a type of food product created and processed for consumption by astronauts during missions to outer space. Such food has specific requirements to provide a balanced diet and adequate nutrition for individuals working in space while being easy and safe to store, prepare and consume in the machinery-filled weightless environments of crewed spacecraft. Space food is commonly freeze-dried to minimize weight and ensure long shelf life. Then, before eating it is rehydrated. Unmodified food such as items of fruit and, even a sandwich, have been brought into space. Packaging varies including tubes, cans, and sealed plastic packages.
Astrobotany is an applied sub-discipline of botany that is the study of plants in space environments. It is a branch of astrobiology and botany.
TROPI, or "Analysis of a Novel Sensory Mechanism in Root Phototropism", is an experiment on the International Space Station (ISS) to investigate the growth and development of plant seedlings under various gravity and lighting combinations. It was launched on Space Shuttle Endeavour during the STS-130 mission and was performed on the ISS during Expedition 22. Frozen plant samples from the TROPI experiment were returned on the landing of the STS-131 mission on Space Shuttle Discovery.
The International Space Station is a platform for scientific research that requires one or more of the unusual conditions present in low Earth orbit. The primary fields of research include human research, space medicine, life sciences, physical sciences, astronomy and meteorology. The 2005 NASA Authorization Act designated the American segment of the International Space Station as a national laboratory with the goal of increasing the use of the ISS by other federal agencies and the private sector.
Planetary Transportation Systems (PTS), formerly known as PTScientists and Part-Time Scientists, is a Berlin-based aerospace company. They developed the robotic lunar lander "ALINA" and seek to land on the Moon with it. They became the first German team to officially enter the Google Lunar X-Prize competition on June 24, 2009, but failed to reach the finals in 2017 for lack of a launch contract. During the summer of 2019, the company filed for bankruptcy, and the ALINA project was put on hold. In July 2021, PTS was selected with ArianeGroup to build ESA's ASTRIS kick-stage.
SpaceX CRS-3, also known as SpX-3, was a Commercial Resupply Service mission to the International Space Station (ISS), contracted to NASA, which was launched on 18 April 2014. It was the fifth flight for SpaceX's uncrewed Dragon cargo spacecraft and the third SpaceX operational mission contracted to NASA under a Commercial Resupply Services (CRS-1) contract.
Space farming refers to the cultivation of crops for food and other materials in space or on off-Earth celestial objects – equivalent to agriculture on Moon.
Expedition 51 was the 51st expedition to the International Space Station, which began upon the departure of Soyuz MS-02 on April 10, 2017, and concluded upon the departure of Soyuz MS-03 on June 2, 2017. Peggy Whitson, Oleg Novitskiy and Thomas Pesquet were transferred from Expedition 50, with Peggy Whitson taking the commander role. She is the first woman to command two expeditions to the ISS, having previously commanded Expedition 16.
A Beautiful Planet is an IMAX Entertainment documentary produced in collaboration with NASA and filmed aboard the International Space Station by astronaut crews. Narrated by Jennifer Lawrence, it was produced and directed by Toni Myers.
Expedition 52 was the 52nd expedition to the International Space Station. It officially began on June 2, 2017 10:47 UTC, with the undocking of Soyuz MS-03. Transfer of command from Expedition 51 was done on June 1, 2017.
The Vegetable Production System (Veggie) is a plant growth system developed and used by NASA in space environments. The purpose of Veggie is to provide a self-sufficient and sustainable food source for astronauts as well as a means of recreation and relaxation through therapeutic gardening. Veggie was designed in conjunction with ORBITEC and went operational aboard the International Space Station in 2014, with another Veggie module added to the ISS in 2017.
Expedition 53 was the 53rd expedition to the International Space Station, which began upon the departure of Soyuz MS-04 on September 2, 2017, and concluded upon the departure of Soyuz MS-05 on December 14, 2017. Randolph Bresnik, Paolo Nespoli and Sergey Ryazansky were transferred from Expedition 52, with Randolph Bresnik taking the commander role. Transfer of Command from Expedition 53 to Expedition 54 was done on December 13, 2017. Expedition 53 officially ended on December 14, 2017 5:14 UTC, with the undocking of Soyuz MS-05.
The ISS U.S. National Lab, commonly known as the ISS National Lab, is a U.S. government-funded national laboratory established on 30 December 2005 by the 2005 NASA Authorization Act. With principal research facilities located in the United States Orbital Segment (USOS) of the International Space Station (ISS), the Laboratory conducts research in life sciences, physical sciences, technology development and remote sensing for a broad range of academic, government and commercial users. Of the 270 payloads that the Center for the Advancement of Science in Space (CASIS) has sent to the ISS, 176 have been for commercial companies including Merck & Co., Novartis, Eli Lilly and Company, Hewlett Packard Enterprise, Honeywell, and Procter & Gamble.
John Z. Kiss is an American biologist known for his work on the gravitational and space biology of plants. Kiss is senior vice president for academic affairs and provost at the Florida Institute of Technology. Previously, he was dean of the College of Arts & Sciences at the University of North Carolina Greensboro. He has also served as dean of the Graduate School at the University of Mississippi. and distinguished professor and chair of the botany department at Miami University. He has worked with NASA since 1987 and served as principal investigator on eight spaceflight experiments on the Space Shuttle, the former Russian space station Mir, and on the International Space Station. His research focuses on the sensory physiology of plants in space. He received the NASA Outstanding Public Leadership Medal in 2014. In 2021, Asteroid Kiss 8267 was named in his honor, a recognition that coincided with his receipt of the 2021 COSPAR International Cooperation Medal. His international collaboration on a spaceflight project with NASA and the European Space Agency has led to the discovery of novel sensory mechanisms in plants.