Astrobotany
[12] There are a number of obstacles to the detection of exoplanetary VREs: Dubbed ‘the creator of astrobotany’,[1] Gavriil Adrianovich Tikhov coined the term in 1945 to describe the emerging field surrounding the search for extraterrestrial vegetation.
[16][21] Accurate description of extraterrestrial vegetation character is highly speculative, but follows "solid physics and atmospheric chemistry" principles, according to Professor John Albert Raven from the University of Dundee.
TRAPPIST-1 is an ultra-cool red dwarf star, providing almost half the energy as the Sun, leading to astrobotanical speculation that vegetation in the TRAPPIST-1 exoplanet system could be much darker, even black to human eyes.
In space, plants encounter unique environmental stressors not found on Earth including microgravity, ionizing radiation, and oxidative stress.
[24] Astrobotanical research has been applied to the challenges of creating life support systems both in space and on other planets, primarily Mars.
Russian scientist Konstantin Tsiolkovsky was one of the first people to discuss using photosynthetic life as a resource in space agricultural systems.
Research in the field has been conducted both with growing Earth plants in space environments and searching for botanical life on other planets.
These early suborbital biological experiments were handled by Harvard University and the Naval Research Laboratory and were concerned with radiation exposure on living tissue.
[26] In 1971, 500 tree seeds (Loblolly pine, Sycamore, Sweetgum, Redwood, and Douglas fir) were flown around the Moon on Apollo 14.
[31] Plants tested in Veggie before going into space included lettuce, Swiss chard, radishes, Chinese cabbage and peas.
[32] 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.
Initial research in the 1950s and 1960s used Chlorella, Anacystis, Synechocystis, Scenedesmus, Synechococcus, and Spirulina species to study how photosynthetic organisms could be used for O2 and CO2 cycling in closed systems.
The first life support systems testing performed in space included gas exchange experiments with wheat, potato, and giant duckweed (Spyrodela polyrhiza).
[51] Future studies have been planned to investigate the effects of keeping plants on the mental well-being of humans in confined environments.
Interlocking closed systems called "modular biospheres" have been prototyped to support four- to five-person crews on the Martian surface.
[55] They are anticipated to use Martian soils for growth substrate and wastewater treatment, and crop cultivars developed specifically for extraplanetary life.
Extensive research into hydroponics systems was fielded successfully by NASA in both the CELSS and ALS programs, as well as the effects of increased photoperiod and light intensity for various crop species.
